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Bacterial cellulose is a biocompatible biomaterial with a unique macromolecular structure. Unlike plant-derived cellulose, bacterial cellulose is produced by certain bacteria, resulting in a sustainable material consisting of self-assembled nanostructured fibers with high crystallinity. Due to its purity, bacterial cellulose is appealing for biomedical applications and has raised increasing interest, particularly in the context of 3D printing for tissue engineering and regenerative medicine applications. Bacterial cellulose can serve as an excellent bioink in 3D printing, due to its biocompatibility, biodegradability, and ability to mimic the collagen fibrils from the extracellular matrix (ECM) of connective tissues. Its nanofibrillar structure provides a suitable scaffold for cell attachment, proliferation, and differentiation, crucial for tissue regeneration. Moreover, its mechanical strength and flexibility allow for the precise printing of complex tissue structures. Bacterial cellulose itself has no antimicrobial activity, but due to its ideal structure, it serves as matrix for other bioactive molecules, resulting in a hybrid product with antimicrobial properties, particularly advantageous in the management of chronic wounds healing process. Overall, this unique combination of properties makes bacterial cellulose a promising material for manufacturing hydrogels and 3D-printed scaffolds, advancing the field of tissue engineering and regenerative medicine.

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Several strategies promote phyllosphere colonization by soil-born Trichoderma plant-beneficial strains. One of these strategies is foliar spraying with suspensions containing large amounts of chlamydospores-spores with thick cell wall structures that make them highly resistant to harsh environmental conditions. Trichoderma biomass was produced by cultivation on a cornmeal medium and compared with the biomass produced on potato dextrose broth by microscopic and thermogravimetric analyses. The analyses revealed increased chlamydospore content and thermostability in the fungal biomass produced on the corn meal medium. The Trichoderma suspension rich in chlamydospores was sprayed on bitter gourd (Momordica charantia) leaves at two inoculant concentrations, 10(6) and 10(8) ufc/mL. The effect of these treatments on the plant physiological parameters, leaf photosynthetic pigments, polyphenol and flavonoid contents, antioxidant activities of the leaves and fruits, and yield was compared to the control (plants sprayed with water) and to the experimental treatment involving spraying with 10(8) ufc/mL of propagules produced in potato dextrose broth. The effect of chlamydospore-rich suspensions on plant physiological parameters was more pronounced and long-lasting compared with the other treatments. The treatment with chlamydospore-rich suspension enhanced the accumulation of polyphenols and flavonoids in the leaves (by 17% and 50%, respectively) and fruits (by 18% and 31%, respectively) and increased the antioxidant activity. The Trichoderma treatment increased the yield by +25.33-53.07%. The application of the foliar treatment with Trichoderma suspensions did not modify the cytocompatibility of the extracts from the fruits determined on the L929 cells.

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Marine glycosaminoglycans (GAG) isolated from different invertebrates, such as molluscs, starfish or jellyfish, have been described as unique molecules with important pharmacological applications. Scarce information is available on GAG extract from Rapana venosa marine snail. The aim of this study was to isolate a GAG extract from R. venosa marine snail and to investigate its physicochemical, antioxidant and antiproliferative properties for further biomedical use. The morphology, chemical and elemental composition of the extract were established as well as the sulfate content and N- to O-sulfation ratio. Fourier transform infrared (FTIR) spectra indicated that GAG extract presented similar structural characteristics to bovine heparan sulfate and chondroitin sulfate. The pattern of extract migration in agarose gel electrophoresis and specific digestion with chondroitinase ABC and heparinase III indicated the presence of a mixture of chondroitin sulfate-type GAG, as main component, and heparan sulfate-type GAG. Free radical scavenging and ferric ion reducing assays showed that GAG extract had high antioxidant activity, which slightly decreased after enzymatic treatment. In vitro MTT and Live/Dead assays showed that GAG extract had the ability to inhibit cell proliferation in human Hep-2 cell cultures, at cytocompatible concentrations in normal NCTC clone L929 fibroblasts. This capacity decreased after enzymatic digestion, in accordance to the antioxidant activity of the products. Tumoral cell migration was also inhibited by GAG extract and its digestion products. Overall, GAG extract from R. venosa marine snail exhibited antioxidant and antiproliferative activities, suggesting its potential use as novel bioactive compound for biomedical applications.

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The present study aimed to conduct a comparative investigation of the biological properties of phenolic and polysaccharide extracts obtained using an ultrasound-assisted technique from Aloe vera gel and their effects on each stage of the wound healing process in in vitro experimental models. HPLC analysis showed that the phenolic extract contained aloin, ferulic, and caffeic acid, as well as quercetin dihydrate, as major compounds. Capillary zone electrophoresis indicated the prevalence of mannose and glucose in the polysaccharide extract. Cell culture testing revealed the anti-inflammatory properties of the phenolic extract at a concentration of 0.25 mg/mL through significant inhibition of pro-inflammatory cytokines—up to 28% TNF-α and 11% IL-8 secretion—in inflamed THP-1-derived macrophages, while a pro-inflammatory effect was observed at 0.5 mg/mL. The phenolic extract induced 18% stimulation of L929 fibroblast proliferation at a concentration of 0.5 mg/mL, enhanced the cell migration rate by 20%, and increased collagen type I synthesis by 18%. Moreover, the phenolic extract exhibited superior antioxidant properties by scavenging free DPPH (IC50 of 2.50 mg/mL) and ABTS (16.47 mM TE/g) radicals, and 46% inhibition of intracellular reactive oxygen species (ROS) production was achieved. The polysaccharide extract demonstrated a greater increase in collagen synthesis up to 25%, as well as antibacterial activity against Staphylococcus aureus with a bacteriostatic effect at 25 mg/mL and a bactericidal one at 50 mg/mL. All these findings indicate that the phenolic extract might be more beneficial in formulations intended for the initial phases of wound healing, such as inflammation and proliferation, while the polysaccharide extract could be more suitable for use during the remodeling stage. Moreover, they might be combined with other biomaterials, acting as efficient dressings with anti-inflammatory, antioxidant, and antibacterial properties for rapid recovery of chronic wounds. © 2024 by the authors.

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The complex composition of honey plays a crucial role in wound healing, exhibiting varying effects at different stages of the healing process. This study investigated seven honey varieties sourced from different regions of Romania using in vitro experimental models developed in macrophage-like, fibroblast, and keratinocyte cell lines to explore the mechanisms by which honey promoted the healing process. This study assessed the impact of honey on inflammatory cytokine production in macrophage-like cells, cell proliferation and collagen synthesis in fibroblasts, and cell proliferation and migration in keratinocytes. Additionally, correlation analysis was conducted to examine the relationship between honey composition and its biological properties. Honey varieties presented both anti- and pro-inflammatory effects. Moreover, they displayed dose-dependent pro-proliferative effects, stimulating collagen synthesis and cell migration, thereby enhancing the re-epithelialization process. The Pearson coefficient analysis indicated a strong positive correlation between biological activities and phenolic content. Additionally, there was a medium positive correlation with the ascorbic acid content and a medium negative correlation with the glucose content in the different honey varieties. Romanian honey varieties rich in phenolics showed potential in modulating inflammation, proliferation, collagen synthesis, and cell migration, suggesting their suitability for further evaluation and development of innovative dressings for skin tissue regeneration.

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This study aimed to evaluate the hypoglycemic potential, antioxidant activity and prebiotic activity of a hydroalcoholic extract of blueberry pomace (BP), an aqueous extract of chia seeds (CS) and a novel combination of BP-CS extracts (BCM) for further use as ingredient of functional food. Spectrometric and HPLC analyses were used to characterize the total phenolic and flavonoid content and composition of BP, while CS was analyzed for total carbohydrate content. Data showed that the BCM mixture exerted an inhibition of alpha-amylase activity, which was 1.36 times higher than that of BP and 1.25 higher than CS extract. The mixture also showed better scavenging activity of free DPPH radicals than individual extracts, and had an IC50 value of 603.12 mu g/mL. In vitro testing indicated that both serum- and colon-reaching products of simulated intestinal digestion of BCM presented the capacity to protect Caco-2 intestinal cells against oxidative stress by inhibition of reactive oxygen species production. In addition, the colon-reaching product of BCM digestion had the capacity to significantly (p < 0.05) stimulate the growth of Lactobacillus rhamnosus and Lactobacillus acidophilus, revealing a prebiotic potential. All these results indicated that improved biological activity of the novel combination of BP and CS extracts could be due to the synergistic action of constituents. The combination is recommended for further testing and the development of novel functional food for controlling type 2 diabetes and gastrointestinal conditions.

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Lonicera caerulea L., (blue honeysuckle, blue honeyberry or haskap) is an Eastern Siberian shrub with fruits known to have potential medicinal applications. The aim of this paper was to investigate the physico-chemical properties, composition and the correlation to the total antioxidant capacity of some fluid extracts of haskap berries for their use as nutraceuticals. The dried fruits were collected from Moldavia region in North-Eastern Romania and the extracts were prepared at a concentration of 10% (w/v) in ethanol concentrations of 50:50 (v:v), 70:30 (v:v) and 96:4 (v:v), respectively. The total content of main bioactive compounds, such as polyphenols, flavonoids, tannins, anthocyanins, carotenoids, lycopene, lutein, vitamin C and carbohydrates was determined by UV-Vis spectrophotometric assays. Total antioxidant capacity of extracts was assessed by photochemiluminescence method, in comparison to Trolox (R), an analogue of vitamin E, used as antioxidant standard. The obtained results emphasized that the hydroalcoholic extract in 70:30 (v:v) ethanol had significantly (p<0.01) higher content of vitamin C, carbohydrates and carotenoids than the other two extracts, and similar quantities of total phenolics, flavonoids, lycopene and lutein, In accordance, the same extract had the highest total antioxidant activity and close to the values of resveratrol, a known antioxidant polyphenolic compound. In conclusion, hydroalcoholic extracts of Lonicera caerulea L. berries could be used as valuable products for the formulation of novel nutraceuticals with significant antioxidant activity.

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Lonicera caerulaea L. and Aronia melanocarpa (Michx.) Elliot fruits are frequently used for their health benefits as they are rich in bioactive compounds. They are recognized as a source of natural and valuable phytonutrients, which makes them a superfood. L. caerulea presents antioxidant activity three to five times higher than other berries which are more commonly consumed, such as blackberries or strawberries. In addition, their ascorbic acid level is the highest among fruits. The species A. melanocarpa is considered one of the richest known sources of antioxidants, surpassing currants, cranberries, blueberries, elderberries, and gooseberries, and contains one of the highest amounts of sorbitol. The non-edible leaves of genus Aronia became more extensively analyzed as a byproduct or waste material due to their high polyphenol, flavonoid, and phenolic acid content, along with a small amount of anthocyanins, which are used as ingredients in nutraceuticals, herbal teas, bio-cosmetics, cosmeceuticals, food and by the pharmaceutical industry. These plants are a rich source of vitamins, tocopherols, folic acid, and carotenoids. However, they remain outside of mainstream fruit consumption, being well known only to a small audience. This review aims to shed light on L. caerulaea and A. melanocarpa and their bioactive compounds as healthy superfoods with antioxidant, anti-inflammatory, antitumor, antimicrobial, and anti-diabetic effects, and hepato-, cardio-, and neuro-protective potential. In this view, we hope to promote their cultivation and processing, increase their commercial availability, and also highlight the ability of these species to be used as potential nutraceutical sources, helpful for human health.

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This study aimed to investigate, for the first time, the chemical composition and antioxidant activity of fluid extracts obtained from three Romanian cultivars of haskap berries (Lonicera caerulea L.) var. Loni, bitter cherries (Prunus avium var. sylvestris Ser.) var. Silva, and pomace from red grapes (Vitis vinifera L.) var. Mamaia, and their capacity to modulate in vitro steatosis, in view of developing novel anti-obesity products. Total phenolic, flavonoid, anthocyanin, and ascorbic acid content of fluid extracts was spectrophotometrically assessed and their free radical scavenging capacity was evaluated using Trolox Equivalent Antioxidant Capacity (TEAC) and free 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical inhibition assays. The Pearson coefficients showed a moderate correlation between the antioxidant activity of fluid extracts and their phenolic content, but a strong correlation between anthocyanin and ascorbic acid content. HPLC analysis identified and quantified the main phenolic compounds of chlorogenic and syringic acid, catechin, and glycosylated kaempferol, apigenin, and quercetin, in variable proportions. An in vitro experimental model of steatosis was developed in HepG2 hepatocytes treated with a mixture of free fatty acids. Cell culture analyses showed that cytocompatible concentrations of fluid extracts could significantly reduce the lipid accumulation and inhibit the reactive oxygen species, malondialdehyde, and nitric oxide secretion in stressed hepatocytes. In conclusion, these results put an emphasis on the chemical compounds' high antioxidant and liver protection capacity of unstudied fluid extracts obtained from Romanian cultivars of bitter cherries var. Silva and pomace of red grapes var. Mamaia, similar to the fluid extract of haskap berries var. Loni, in particular, the positive modulation of fat deposition next to oxidative stress and the lipid peroxidation process triggered by fatty acids in HepG2 hepatocytes. Consequently, this study indicated that these fluid extracts could be further exploited as hepatoprotective agents in liver steatosis, which provides a basis for the further development of novel extract mixtures with synergistic activity as anti-obesity products.

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Diabetes is a condition correlated with a high number of diagnosed chronic wounds as a result of a complex pathophysiological mechanism. Diabetic chronic wounds are characterized by disorganized and longer stages, compared to normal wound healing. Natural polymer hydrogels can act as good wound dressings due to their versatile physicochemical properties, represented mainly by high water content and good biocompatibility. Natural bioactive hydrogels are polymers loaded with bioactive compounds providing antibacterial and antioxidant properties, modulation of inflammation and adherence to wounded tissue, compared to traditional dressings, which enables promising future applications for diabetic wound healing. Natural bioactive compounds, such as polyphenols, polysaccharides and proteins have great advantages in promoting chronic wound healing in diabetes due to their antioxidant, anti-inflammatory, antimicrobial, anti-allergic and wound healing properties. The present paper aims to review the wound healing mechanisms underlining the main issues of chronic wounds and those specifically occurring in diabetes. Also, the review highlights the recent state of the art related to the effect of hydrogels enriched with natural bioactive compounds developed as biocompatible functional materials for improving diabetic-related chronic wound healing and providing novel therapeutic strategies that could prevent limb amputation and increase the quality of life in diabetic patients.

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A major clinical challenge today is the large number of bone defects caused by diseases or trauma. The development of three-dimensional (3D) scaffolds with adequate properties is crucial for successful bone repair. In this study, we prepared biomimetic mesoporous bioactive glass (MBG)-based scaffolds with and without ceria addition (up to 3 mol %) to explore the biological structure and chemical composition of the marine sponge Spongia Agaricina (SA) as a sacrificial template. Micro-CT examination revealed that all scaffolds exhibited a highly porous structure with pore diameters primarily ranging from 143.5 mu m to 213.5 mu m, facilitating bone ingrowth. Additionally, smaller pores (< 75 mu m), which are known to enhance osteogenesis, were observed. The undoped scaffold displayed the highest open porosity value of 90.83%. Cytotoxicity assessments demonstrated that all scaffolds were noncytotoxic and nongenotoxic toward osteoblast cells. Moreover, scaffolds with higher CeO2 content promoted osteogenic differentiation of dental pulp stem cells, stimulating calcium and osteocalcin secretion. The scaffolds also exhibited antimicrobial and antibiofilm effects against Staphylococcus aureus (S. aureus) as well as drug delivery ability. Our research findings indicated that the combination of MBG, natural biological structure, and the addition of Ce exhibited a synergistic effect on the structure and biological properties of scaffolds for applications in bone tissue engineering.

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Osteochondral structure reconstruction by tissue engineering, a challenge in regenerative medicine, requires a scaffold that ensures both articular cartilage and subchondral bone remodeling. Functional hydrogels and scaffolds present a strategy for the controlled delivery of signaling molecules (growth factors and therapeutic drugs) and are considered a promising therapeutic approach. Icariin is a pharmacologically-active small molecule of prenylated flavonol glycoside and the main bioactive flavonoid isolated from Epimedium spp. The in vitro and in vivo testing of icariin showed chondrogenic and ostseoinductive effects, comparable to bone morphogenetic proteins, and suggested its use as an alternative to growth factors, representing a low-cost, promising approach for osteochondral regeneration. This paper reviews the complex structure of the osteochondral tissue, underlining the main aspects of osteochondral defects and those specifically occurring in osteoarthritis. The significance of icariin's structure and the extraction methods were emphasized. Studies revealing the valuable chondrogenic and osteogenic effects of icariin for osteochondral restoration were also reviewed. The review highlighted th recent state-of-the-art related to hydrogels and scaffolds enriched with icariin developed as biocompatible materials for osteochondral regeneration strategies.

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The aim of this study was to investigate the main volatiles and polyphenolic compounds in hydrosols extracted from three Romanian Lamiaceae plants, sage (Salvia officinalis), rosemary (Rosmarinus officinalis) and lavender (Lavandula angustifolia) by steam distillation. The antioxidant and acetylcholinesterase inhibition capacity of hydrosols were assessed for their further use as biopesticides. The results have shown that sage and rosemary hydrosols presented better antioxidant activity than lavender hydrosol in all free radical scavenging and metal chelating assays. A strong relationship between the antioxidant activity of hydrosols' and their total phenolic and flavonoid content was found based on Pearson correlation coefficients. Sage and rosemary hydrosols exerted higher acetylcholinesterase inhibition than lavender hydrosol, but this activity was moderate correlated to phenolic content and low correlated to flavonoid content. These results suggested that volatiles and other compounds present in hydrosols were also involved in this process. In conclusion, Lamiaceae plant hydrosols could be further tested, as such or mixed, as natural products for the control of pests in eco-agrosystems.

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This study aimed to investigate the free radicals scavenging, inhibition of acetylhydrolase and antimicrobial activity of five mixtures of hydrolates obtained by hydrodistillation of Lamiaceae plants, Rosmarinus officinalis, Salvia officinalis and Lavandula angustifolia. Chemical composition of hydrolates was analysed by gas chromatography coupled with mass spectrometry for volatiles and UV-VIS spectrophotometry for total phenolic and flavonoid content. The results of free radicals scavenging and acetylhydrolase inhibition activity have shown improved effect of selected hydrolates mixtures, compared to individual hydrolates. The effect was in accordance to their polyphenolic content, indicating synergistic action of the combined biologic active compounds from different extracts of rosemary, sage and lavender. In turn, the antimicrobial activity of hydrolates mixtures was similar to that of individual hydrolates in Staphylococcus aureus, Pseudomonas aeruginosa and Rhizoctonia solani cultures, revealing no synergistic effect of volatiles, as mainly responsible compounds. In conclusion, selected mixtures of aromatic plant hydrolates can provide added value to these by-products through further development of natural pesticide and/or fungicide products useful for the ecological crop protection.

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The aim of this study was to investigate the melissopalynology, physicochemical characteristics, antioxidant and antibacterial activity of seven honey samples harvested from different geographical regions and climates of Romania. The melissopalynological analysis revealed that monofloral and multifloral samples contained a wide diversity of minor pollen types from Romanian flora. The moisture, pH and free acidity values were within international limit. HPLC analysis indicated high content of fructose and glucose and low content of sucrose. Bioactive compounds including proteins, phenolics, flavonoids and ascorbic acid were present in variable quantities, according to the botanical origin and geographical area. The highest phenolics and ascorbic acid content was in multifloral honeys from Crisana mountain and meadow and the extrafloral honeydew honey. The same honey samples have exerted free radical scavenging and antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa. The free radical scavenging activity was strongly correlated to phenolics and ascorbic acid content, while the antimicrobial activity was medium correlated only to phenolics content. In conclusion, the selected Romanian honey samples with best antioxidant and antimicrobial activity could be further tested for the development of novel biomedical products.

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Research background. Various protocols for enzymatic hydrolysis of fish by-products are increasingly tested to ensure value-added products with functional and biological properties important for food, cosmetic and medical applications. In addition, they attempt to minimize waste from industrial processing and environmental requirements. This study aims to establish an efficient protocol based on two-step enzymatic hydrolysis of freshwater fish skin and to evaluate the effect of resulting bioactive peptides on free radical scavenging, redox balance and regulation of fibroblast proliferation and migration. Experimental approach. Pepsin-soluble collagen extracted from silver carp (Hypophthalmichthys molitrix) skin was hydrolyzed by proteinase K at specific sites under controlled conditions. The molecular mass of ultrafiltration permeate was determined by gradient electrophoresis and gel filtration chromatography. The biological activity of intermediate and small size bioactive peptides was evaluated in experimental models in vitro mimicking oxidative stress and skin wound conditions. Results and conclusions. Extracted fish collagen was hydrolysed using proteinase K, the most efficient enzyme for the cleavage of the primary structure of the molecule, as previously found in silico. Established optimal conditions increased the enzyme specificity and the process yield. Bioactive peptides exerted significantly higher scavenging activity on free stable radicals and hydroxyl radicals often found in vivo, compared to fish collagen. They stimulated fibroblast metabolism in a dose-dependent manner and up-regulated cell migration in a scratch wound model. Pretreatment of fibroblasts with induced oxidative stress using optimal concentrations of fish peptides prevented the increase of reactive oxygen species production. In conclusion, bioactive peptides from carp skin demonstrated valuable properties of maintaining redox balance and skin wound healing process improvement, which indicated further potential applications in the development of pharmaceutical and nutraceutical formulations. Novelty and scientific contribution. In this study the enzymatic hydrolysis was applied to isolated protein, in contrast to previous studies using waste tissue with variable composition. Recovered bioactive peptides acted not only as antioxidant agents, but also as regulators of oxidative stress and wound healing processes in skin cell models. Their nutritional and cosmetic application is recommended in novel formulations fighting skin ageing phenomena.

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Finding innovative solutions to improve the lives of people affected by trauma, bone disease, or aging continues to be a challenge worldwide. Tissue engineering is the most rapidly growing area in the domain of biomaterials. Cerium-containing MBG-derived biomaterials scaffolds were synthesized using polymethyl methacrylate (PMMA) as a sacrificial template. The obtained scaffolds were characterized by X-ray powder diffraction (XRPD), infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The Ce4+/Ce3+ ratio in the scaffolds was estimated. In vitro testing revealed good cytocompatibility of the investigated scaffolds in mouse fibroblast cell line (NCTC clone L929). The results obtained regarding bioactivity, antibacterial activity, and controlled drug delivery functions recommend these scaffolds as potential candidates for bone tissue engineering applications.

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A red-emitting fluorescent Riboflavin (RF)/Polyvinylpyrrolidone (PVP)-coated silver nanoparticles system, lambda(em) = 527 nm, phi = 0.242, with a diameter of the metallic core of 27.33 nm and a zeta potential of - 25.05 mV was prepared and investigated regarding its biological activity. We found that PVP has a key role in RF adsorption around the SNPs surface leading to an enhancement of antioxidant properties (similar to 70%), low cytotoxicity (> 90% cell viability, at 50 mu L/mL, after 48 h of incubation) as well as to an efficient process of its cellular uptake (similar to 60%, after 24 h of incubation) in L929 cells. The results are relevant concerning the involvement of RF and its coenzymes forms in SNPs - based systems, in cellular respiration as well as for future studies as antioxidant marker system on tumoral cells for viewing and monitoring them, by cellular imaging.

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Over the past years, research attention has been focusing more on waste-derived, naturally derived, and renewable materials, in the view of a more sustainable economy. In this work, different topical formulations were obtained from the valorization of marine and agro-industrial by-products and the use of Carbopol 940 as gelling agent. In particular, the combination of extracts obtained from the marine snail, Rapanosa venosa, with Cladophora vagabunda and grape pomace extracts, was investigated for wound healing purposes. Rapana venosa has demonstrated wound healing properties and antioxidant activity. Similarly, grape pomace extracts have been shown to accelerate the healing process. However, their synergic use has not been explored yet. To this aim, four different formulations were produced. Three formulations differed for the presence of a different extract of Rapana venosa: marine collagen, marine gelatin, and collagen hydrolysate, while another formulation used mammalian gelatin as further control. Physico-chemical properties of the extracts as well as of the formulations were analyzed. Furthermore, thermal stability was evaluated by thermogravimetric analysis. Antioxidant capacity and biological behavior, in terms of cytocompatibility, wound healing, and antimicrobial potential, were assessed. The results highlighted for all the formulations (i) a good conservation and thermal stability in time, (ii) a neutralizing activity against free radicals, (iii) and high degree of cytocompatibility and tissue regeneration potential. In particular, collagen, gelatin, and collagen hydrolysate obtained from the Rapana venosa marine snail represent an important, valuable alternative to mammalian products.

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Background: New materials are currently designed for efficient treatment of oral tissue lesions by guided tissue regeneration. The aim of this study was to develop a multifunctional 3D hybrid biomaterial consisting of extracellular matrix components, collagen, chondroitin 4-sulfate and fibronectin, functionalised with silver nanoparticles, intended to improve periodontitis treatment protocols. Methods: Structural observations were performed by autometallography, scanning and transmission electron microscopy. In vitro tests of 3D constructs of embedded gingival fibroblasts within hybrid biomaterial were performed by MTS and Live/Dead assays. Genotoxicity was assessed by comet assay. In vivo experiments using chick embryo chorioallantoic membrane (CAM) assay analysed the degradation and nanoparticles release, but also angiogenesis, new tissue formation in 3D constructs and the regenerative potential of the hybrid material. Biological activity was investigated in experimental models of inflamed THP-1 macrophages and oral specific bacterial cultures. Results: Light micrographs showed distribution of silver nanoparticles on collagen fibrils. Scanning electron micrographs revealed a microstructure with interconnected pores, which favoured cell adhesion and infiltration. Cell viability and proliferation were significantly higher within the 3D hybrid biomaterial than in 2D culture conditions, while absence of the hybrid material?s genotoxic effect was found. In vivo experiments showed that the hybrid material was colonised by cells and blood vessels, initiating synthesis of new extracellular matrix. Besides the known effect of chondroitin sulfate, incorporated silver nanoparticles increased the antiinflammatory activity of the hybrid biomaterial. The silver nanoparticles maintained their antibacterial activity even after embedding in the polymeric scaffold and inhibited the growth of F. nucleatum and P. gingivalis. Conclusion: The novel biomimetic scaffold functionalised with silver nanoparticles presented regenerative, antiinflammatory and antimicrobial potential for oral cavity lesions repair.

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Tomato peels are used as a valuable material to extract lycopene-rich oleoresins by supercritical CO2 extraction. The extraction involves continuous circling of CO2 to the extractor after removing the solute in the separators, S40 and S45, where the solvent power of the CO2 is reduced by reducing pressure down to 20 MPa in S40 and 5 MPa in S45, respectively, leading to two extracts. Lycopene is found to be the major compound, representing 93% and 76% of the total carotenoids in S40 and S45 extracts, respectively. The two extracts are microencapsulated in whey protein concentrate and acacia gum by complex coacervation and freeze-drying, leading to corresponding P40 and P45 powders, with antioxidant activity of 8.57 +/- 0.74 and 9.37 +/- 0.48 mMol TEAC/g DW in P40 and P45, respectively. Different structural and morphological patterns are observed, with finer microparticles of 1-2 mu m in P45. Both powders show dose and time-dependent antiproliferative activity. The half-maximal inhibitory concentration values are 100 mu g/mL for P40 and 750 mu g/mL for P45 sample, indicating a higher antiproliferative effect of P40 over P45 in HT-29 cell culture. The powders have an extended range of cytocompatibility, up to 1000 mu g/mL, in L929 normal cells, stimulating the cell growth. Lycopene retention is tested, and values of 48% and 29% in P40 and P45 are found after 21 days at 25 degrees C, with the degradation rate in P45 significantly higher, due to the higher content of the surface lycopene, which favored its degradation.

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Significant quantities of onion are cultivated annually, such that industrial processing leads to an appreciable amount of by-products, estimated at around 500,000 tons. Onion skins are considered an important source of naturally occurring antioxidant compounds, particularly flavonoid compounds. Our study follows the development of a sustainable solution in order to manage the by-products of yellow onion skins by designing ingredients with multifunctional activities. A green solvent aqueous extraction of flavonoids was applied to obtain a safe, flavonoid-enriched extract, yielding a total flavonoid content of 50.21 +/- 0.09 mg quercetin equivalent (QE)/g dry weight (DW), and an antioxidant activity of 250.81 +/- 6.76 mM Trolox/g DW. Complex biopolymeric matrices consisting of whey protein isolates, whey protein hydrolysates, maltodextrin, and pectin were further dissolved in the flavonoid-enriched aqueous extract, followed by freeze-drying. Two powders were obtained, both showing satisfactory phytochemical content and good stability during storage. The application of confocal microscopy revealed that the microscopic structure of the powders have a distribution of the bioactive compounds within the biopolymeric matrices. The in vitro digestion suggested remarkable stability in the gastric tract and a flavonoid-controlled release in the intestinal phase. A significant compatibility range of up to 1 mg/mL for both powders was found, whereas concentrations between 10 and 250 mu g/mL stimulated cell proliferation after 24 h of cultivation. The powders showed satisfactory thermal and pH stability, which favors their addition to different food matrices.

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Severe skin injuries, including burns, represent a real concern for the global health-care system and therefore, there is an increased interest in developing wound dressings, in order to stimulate and enhance skin tissue repair. The aim of this study was to design novel hybrid materials, biomimetic to skin extracellular matrix and enriched with silver nanoparticles (nAg), in order to provide both dermal tissue regeneration and antimicrobial activity. Two material variants (variant A and variant B) consisting of type I collagen (COL), chondroitin sulfate (CS) and k-elastin peptides (EL) enriched with positively-charged nAg, were conditioned as membranes. UV exposure ensured both sterilisation and cross-linking of the materials. Physico-chemical characterization of the hybrid biomaterials showed values of density and swelling degree higher than those of COL membrane, while the process of in vitro degradation followed a similar pattern. Infrared spectroscopy and x-ray diffraction indicated alterations of the characteristic structural features and crystallinity of COL after blending with CS and EL and nAg embedding. Scanning electron microscopy observations revealed different surface morphologies of the hybrid membranes, according to their composition. In vitro studies on L929 fibroblasts and HaCaT keratinocytes showed that both hybrid membranes exhibited good cytocompatibility and promoted higher cell proliferation compared to COL sample, as evaluated by MTT and Live/Dead assays. The presence of actin filaments highlighted by fluorescent labelling confirmed the fibroblast and keratinocyte adhesion onto the surface of hybrid membranes. Most importantly, both materials showed an increased wound healing ability in an in vitro scratch assay model, stimulating cell migration at 24 h post-seeding. In addition, good antimicrobial activity was recorded, especially against Gram-positive bacterial strain. Altogether, our findings recommend COL-CS-EL-nAg hybrid membranes as good candidates for wound healing acceleration and bioengineering of skin tissue.

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Osteoarthritis (OA) is a degenerative joint disease. An objective of the nanomedicine and drug delivery systems field is to design suitable pharmaceutical nanocarriers with controllable properties for drug delivery and site-specific targeting, in order to achieve greater efficacy and minimal toxicity, compared to the conventional drugs. The aim of this review is to present recent data on natural bioactive compounds with anti-inflammatory properties and efficacy in the treatment of OA, their formulation in lipid nanostructured carriers, mainly liposomes, as controlled release systems and the possibility to be intra-articularly (IA) administered. The literature regarding glycosaminoglycans, proteins, polyphenols and their ability to modify the cell response and mechanisms of action in different models of inflammation are reviewed. The advantages and limits of using lipid nanoformulations as drug delivery systems in OA treatment and the suitable route of administration are also discussed. Liposomes containing glycosaminoglycans presented good biocompatibility, lack of immune system activation, targeted delivery of bioactive compounds to the site of action, protection and efficiency of the encapsulated material, and prolonged duration of action, being highly recommended as controlled delivery systems in OA therapy through IA administration. Lipid nanoformulations of polyphenols were tested both in vivo and in vitro models that mimic OA conditions after IA or other routes of administration, recommending their clinical application.

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The present study describes a comprehensive investigation of the spectroscopic characteristics, stability and in vitro antioxidant and cytotoxic properties of the Flavin MonoNucleotide (FMN) and Flavin Adenine Dinucleotide (FAD) in Dextran70 (Dx70) and Dx70/phospatidylcholine (PC) biomimetic systems by means of the UV-Vis absorption, fluorescence spectroscopy, chemiluminescence and Neutral Red assay. The affinity of FMN, FAD and the precursor riboflavin (RF) to an unsaturated phospholipid bilayer model as well as the location of the probes within the lipid bilayer were assessed from united-atom molecular dynamics simulations carried out on an unsaturated phospholipid bilayer model system, and the theoretical and experimental characterization of the two probes within biomembranes was complemented with the light microscopy survey of the cell morphology of L929 fibroblast cells cultivated in the presence of various dosage of FAD/FMN. In lipid bilayers, FMN/FAD resulted in a noticeable improvement of the antioxidant activity (the scavenging of reactive oxygen species up to 40%) and a significant effect on cellular viability in the L929 fibroblast cells. The results are important in the oxidative stress process concerning the redox reactions of flavins in humans as well as in further studies on different systems belonging to the category of flavoenzymes/flavoproteins, required for cellular respiration. (C) 2020 Elsevier B.V. All rights reserved.

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In recent years, the rising number of bone diseases which affect millions of people worldwide has led to an increased demand for materials with restoring and augmentation properties that can be used in therapies for bone pathologies. In this work, PMMA- MBG composite scaffolds containing ceria (0, 1, 3 mol%) were obtained by the phase separation method. The obtained composite scaffolds were characterized by X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. UV-Vis measurement and EDX analysis confirmed the presence of cerium ions in the composite scaffolds. Evaluation of the in-vitro biocompatibility using MTT assay showed that composite scaffold containing 1 mol% of ceria presented higher viability than control cells (100%) for concentrations ranging between 5 and 50% after 96 h of incubation.

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In the present study, we evaluated for the first time the photoprotective effect of fish bone bioactive peptides (FBBP) preparation isolated from silver carp (Hypophthalmichthys molitrix) discarded tissue using in vitro experimental models of skin cells exposed to ultraviolet B (UVB) irradiation and stressing agents. FBBP preparation was obtained by papain treatment of minced bones and centrifugal ultrafiltration, and the molecular weight (MW) distribution was characterized by size exclusion and reversed-phase high performance liquid chromatography (RP-HPLC). In vitro assessment of the effect of FBBP pretreatment in UVB-irradiated L929 fibroblasts and HaCaT keratinocytes revealed their cytoprotective activity. Their capacity to efficiently reduce reactive oxygen species (ROS) production and lipid peroxidation varied in a dose-dependent manner, and it was greater in fibroblasts. A decrease of proinflammatory cytokines secretion, in particular of tumor necrosis factor alpha (TNF-alpha), was found after FBBP pretreatment of THP-1-derived inflamed macrophages. Melanin production and tyrosinase activity investigated in UVB-irradiated Mel-Juso cells were lowered in direct relation to FBBP concentrations. FBBP fractions with high radical scavenging activity were separated by ion exchange chromatography, and two collagenic sequences were identified. All these results offer new scientific data on aquaculture fish bone-derived peptides confirming their ability to control the antioxidant, anti-inflammatory and pigmentation processes developed during UV irradiation of skin cells and recommend their use as valuable natural ingredients of photoprotective cosmeceutical products.

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Acid-soluble, undenatured, type I collagen (BSC) isolated, for the first time, from gilthead bream skin and the novel fabricated 3D porous wound dressing were analyzed for physicochemical and biological properties, in order to offer a safe alternative to commercial bovine collagen (BC) products. SDS-polyacrylamide analysis confirmed the purity of BSC preparation. The hydroxyproline content and temperature of denaturation of BSC were lower than those of BC, in accordance with the structural data recorded by FT-IR spectroscopy. However, certain concentrations of BSC stimulated the cell metabolism of L929 fibroblasts in a higher proportion than BC. The 3D wound dressing presented high porosity and low surface hydrophobicity that could help cell attachment and growth. The rapid biodegradation of BSC wound dressing could explain the improved in vitro cell migration and wound closure rate. In conclusion, the skin of gilthead bream from the Black Sea coast represented a valuable source for the biomedical industry, providing biocompatible, biodegradable collagen and 3D porous wound dressing, as novel material with enhanced wound healing activity.

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In this study, flavonoids extracted from yellow onion skins and Lactobacillus casei were encapsulated in a combination of whey protein isolate, inulin and maltodextrin with an encapsulation efficiency of 84.82 +/- 0.72% for flavonoids and 72.49 +/- 0.11% for lactic acid bacteria. The obtained powder showed a flavonoid content of 89.49 +/- 4.12 mg quercetin equivalents/g dry weight (DW) and an antioxidant activity of 39.27 +/- 0.45 mM Trolox/g DW. The powder presented a significant antidiabetic and anti-inflammatory potential, with an inhibitory effect on alpha-amylase, lipase and lipoxygenase of 76.40 +/- 2.30%, 82.58 +/- 3.36% and 49.01 +/- 0.62%, respectively. The results obtained for in vitro digestion showed that the coating materials have a protective effect on the flavonoids release. Cytotoxicity results indicated that the powder was cytocompatible up to a concentration of 500 mu g/mL. The functional potential of the powder was tested by adding in a selected food matrix, highlighting a good stability of the phytochemicals, whereas an increase with 1 log cell forming unit (CFU)/g DW was observed after 21 days of storage. The obtained results are promising in the valorization of natural antioxidants in combination with lactic acid bacteria in order to develop multifunctional ingredients with value-added for food and pharmaceutics applications.

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Fermented bovine colostrum rich in bioactive peptides was obtained using Candida lipolytica strains in co-culture with kefir grains. During fermentation, the pH and total titratable acidity of the product were daily measured. The hydrolysis degree and the electrophoretic pattern of water-soluble extracts (WSE) of fermented colostrum were analysed. Fractions enriched in peptides with a molecular weight lower than 10 kDa were separated by ultracentrifugation. They showed better modulation of angiotensin-converting enzyme (ACE) inhibition and cell proliferation, but lower radical scavenging capacity, compared to corresponding WSE.

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Lavender flowers were used in this study as a source of phytochemicals as naturally occurring antioxidants. Two different extraction techniques were applied, such as ultrasound-assisted (UAE) and supercritical fluids (SCE) methods. The comparative evaluation of the phytochemicals profile evidenced a higher content of chlorophyll a and b of 5.22 +/- 0.12 mg/g dry weight (D.W.) and 2.95 +/- 0.16 mg/g D.W, whereas the carotenoids content was 18.24 +/- 0.04 mg/g D.W. in the SCE extract. Seven main compounds were found in both extracts: beta-linalool, eucalyptol, linalool acetate, beta-trans-ocimene, and limonene in SCE and linalool acetate, beta-linalool, 6-methyl-2-(2-oxiranyl)-5-hepten-2-ol, linalool oxide, lavandulyl acetate and camphor in UAE. The (n-3) acids had a higher contribution in SCE. The extracts were microencapsulated in different combinations of wall materials based on polysaccharides and milk proteins. The four variants showed different phytochemical and morphological profiles, with a better encapsulating efficiency for proteins (up to 98%), but with a higher content of encapsulated carotenoids for polysaccharides, the latter showing remarkable antimicrobial activity against selected microorganisms. Carboxymethyl cellulose and whey proteins led to a double encapsulation of lipophilic compounds. The powders were tested in two food matrices as ingredients, with multiple targeted functions, such as flavoring, antimicrobial, antioxidant activity that can successfully replace synthetic additives.

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Two chitosan extracts were prepared by chemical and enzymatic treatment of Ganoderma lucidum mushroom, as an alternative source to crustacean shells. The molecular weight of the enzymatic extract was lower than that of the chemical one and of shrimp chitosan, as determined by viscosity measurements. Characteristic signals were identified in the H-1-NMR spectra and high deacetylation degree indicated good physico-chemical properties for both mushroom chitosan extracts. The scavenging capacity of mushroom chitosan extracts was moderate against the synthetic radicals of 2,2 '-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH), but higher values were observed for the enzymatic extract, compared to the chemical extract and shrimp chitosan. In vitro cytotoxicity was evaluated in L929 mouse fibroblast cell lines and the results of MTT assay showed good cytocompatibility in the tested range of concentrations. The growth of Gram-positive bacteria was inhibited more than Gram-negative bacteria in the presence of mushroom chitosan extracts, in particular by the chemical one, indicating their efficiency as antimicrobial agents. All these results strengthen the evidence of mushroom polysaccharide preparations availability for biomedical applications.

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This study focuses on combining different bioprocessing tools in order to develop an in-depth engineering approach for enhancing the biological properties of two valuable food by-products, namely fish waste and yellow onion skins, in a single new bioactive formulation. Bone tissue from phytophagous carp (Hypophthalmichthys molitrix) was used to obtain bioactive peptides through papain-assisted hydrolysis. The peptides with molecular weight lower than 3 kDa were characterized through MALDI-ToF/ToF mass spectrometry and bioinformatics tools. As a prerequisite for microencapsulation, the ability of these peptides to bind the flavonoids extracted from yellow onion skins was further tested through fluorescence quenching measurements. The results obtained demonstrate a considerable binding potency with a binding value of 10(6) and also the presence of one single or one class of binding site during the interaction process of flavonoids with peptides, in which the main forces involved are hydrogen bonds and van der Waals interactions. In the freeze-drying microencapsulation process, an efficiency for total flavonoids of 88.68 +/- 2.37% was obtained, considering the total flavonoids and total polyphenols from the powder of 75.72 +/- 2.58 quercetin equivalents/g dry weight (DW) and 97.32 +/- 2.80 gallic acid equivalents/g DW, respectively. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test on the L929 cell line cultivated in the presence of different concentrations of microencapsulated samples (0.05-1.5 mg/mL) proved no sign of cytotoxicity, the cell viability being over 80% for all the samples.

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Skin wound dressings are commonly used to stimulate and enhance skin tissue repair. Even if wounds seem easy to repair for clinicians and to replicate in an in vitro set-up for scientists, chronic wounds remain currently an open challenge in skin tissue engineering for patients with complementary diseases. The seemingly simple process of skin healing hides a heterogenous sequence of events, specific timing, and high level of organization and coordination among the involved cell types. Taken together, all these aspects make wound healing a unique process, but we are not yet able to completely repair the chronic wounds or to reproduce them in vitro with high fidelity. This review highlights the main characteristics and properties of a natural polymer, which is widely used as biomaterial, namely collagen and of its denatured form, gelatin. Available wound dressings based on collagen/gelatin and proposed variants loaded with bioactive compounds derived from plants are presented. Applications of these composite biomaterials are discussed with emphasis on skin wound healing. A perspective on current issues is given in the light of future research. The emerging technologies support the development of innovative dressings based exclusively on natural constituents, either polymeric or bioactive compounds. (C) 2019 Elsevier B.V. All rights reserved.

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The aqueous anthocyanin-rich extract derived from black rice (Oryza sativa L.) was encapsulated by freeze drying using milk proteins and peptides as coating materials. The molecular modelling approach indicated that all major casein fractions and whey proteins were able to bind at least one anthocyanin molecule. The hydrophobic interactions and hydrogen bonding across the interfaces appeared to be mainly responsible for the stabilizations of the complexes formed between the coating material and bioactive compounds. Two dark purple colored powders, differentiated by the ratio of the encapsulation materials used, rich in phytochemicals were obtained, with an encapsulation efficiency of up to 99%. The powders were tested for antioxidant activity, cytocompatibility, and thermal stability. The morphological structure of the powders highlighted the presence of encapsulated anthocyanins. Both powders showed a remarkable antioxidant activity of about 46 mM Trolox/g D.W., and cytocompatibility on the L929 fibroblast culture. At certain concentrations, both powders stimulated cell proliferation. The powders showed a good thermal stability between 75 and 100 degrees C for 15 min. The powders were tested in a food model system and checked for stability of phytochemicals during storage. The added value of the powders was demonstrated throughout the antioxidant activity, which remained unchanged during storage.

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Composite materials containing natural biocompatible polymers, specific for the extracellular matrix present in the periodontal tissue, are prepared by mixing type I soluble collagen (COL) and fibronectin (FN) as fibrillar proteins and chondroitin sulfate (CS) as polysaccharidic component. The threedimensional porous structure is obtained by freeze-drying process and it is analyzed by scanning electron microscopy (SEM). Specific techniques of immunohistochemistry and transmission electron microscopy (TEM) are used to investigate the distribution and interaction between polymeric components within the scaffold. Light and electron microscopy observations are also performed on solutions of CS and FN to reveal their structural and morphological properties. The cytocompatibility of composite material is tested in gingival fibroblasts and osteoblast cell cultures using quantitative assays of cell viability. The results demonstrate that COL-CS-FN composite material has optimal characteristics for further testing as device for oral tissue wound healing.

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Several therapeutic strategies are currently in development for severe periodontitis and other associated chronic inflammatory diseases. Guided tissue regeneration of the periodontium is based on surgical implantation of natural or synthetic polymers conditioned as membranes, injectable biomaterials (hydrogels), or three-dimensional (3D) matrices. Combinations of biomaterials with bioactive factors represent the next generation of regenerative strategy. Cell delivery strategy based on scaffold-cell constructs showed potential in periodontitis treatment. Bioengineering of periodontal tissues using cell sheets and genetically modified stem cells is currently proposed to complete existing (pre)clinical procedures for periodontal regeneration. 3D structures can be built using computer-assisted manufacturing technologies to improve the implant architecture effect on new tissue formation. The aim of this review was to summarize the advantages and drawbacks of biomimetic composite matrices used as biomaterials for periodontal tissue engineering. Their conditioning as two-dimensional or 3D scaffolds using conventional or emerging technologies was also discussed. Further biotechnologies are required for developing novel products tailored to stimulate periodontal regeneration. Additional preclinical studies will be useful to closely investigate the mechanisms and identify specific markers involved in cell-implant interactions, envisaging further clinical tests. Future therapeutic protocols will be developed based on these novel procedures and techniques.

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Eggplant peels (Solanum melongena L.) constitute a promising source of phenolic compounds, flavonoids, and anthocyanins that are beneficial for human health. The objectives of this study were to extract the polyphenolics from eggplant peels and microencapsulation in selected polymers, such as pectin, carboxymethylcellulose and whey proteins hydrolysates by freeze-drying. A combination of ethanolic with ultrasound-assisted methods was used for the extraction, leading to an extract with antioxidant activity of 157.82 +/- 9.46mmol Trolox/g dry weight. The next experiment was to obtain bioactive peptide, both by experimental and predictive methods, which were further used as coating materials. The bioinformatics tools were used for checking the susceptibility of alpha-lactalbumin and beta-lactoglobulin for digestion with thermolysin. The anthocyanins were encapsulated in different combinations of selected polymers, with encapsulation efficiency up to 77.60 +/- 1.92%, highlighting a higher microencapsulation efficiency of carboxymethylcellulose to incorporate anthocyanins. Our results suggested whey peptides had a role in regulating the microencapsulation patterns, whereas carboxymethylcellulose and pectin favored filamentous structuring and double encapsulation, respectively. The in vitro tests showed high biocompatibility of powders cultivated in a cell culture of murine fibroblasts. A significant protective effect in simulated digestion was observed, with a controlled release in the intestinal juice. Accelerated storage stability test showed an increase in antioxidant activity.

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In this study, three of the saponins present in leaves of Hedera helix L., alpha-hederin, hederagenin, and hederacoside C were studied for their antiproliferative activity. The three saponins were analyzed in different concentrations by in vitro tests on normal fibroblasts cells and cervix ephitelial tumor cells. Determination of cytotoxicity and antitumor effects was performed using the MTT method. From the tested saponins, a-hederin was biocompatible in normal fibroblasts cells at concentrations between 2-10 mu g/mL. Its antiproliferative activity was exerted in the concentration range of 10-400 mu g/mL in cervix ephitelial tumor cells. Similarly, hederagenin presented antiproliferative activity at concentrations between 25-400 mu g/mL. In turn, hederacoside C was shown to be noncytotoxic in normal fibroblasts and cervix ephitelial tumor cell culture at all the tested concentrations. The obtained experimental results were analyzed by Mixture design, a specialized form of the response surface method (RSM) provided by the Design Expert 11 software, and the optimal composition of obtained saponins mixture was selected and verified in vitro for antiproliferative activity. The results showed that an optimal saponins mixture has the potential to be used in pharmacological applications.

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Hederagenin, a saponin known for its therapeutic effect was isolated from leaves of Hedera helix. Hederagenin was obtained by repeated maceration of ground plant material in 95% (v/v) ethanol. The ethanolic extract was subjected to acid hydrolysis and purification with acetonitrile. Isolated hederagenin (IHe) was analyzed by HPLC-MS/MS and compared to standard hederagenin. In vitro cytotoxicity of IHe was tested in a culture of fibroblast cells from NCTC clone L929 cell line by MTT assay, using dioscin as positive control. For the determination of IHe antitumor effect, in vitro tests were performed in a culture of human cervix carcinoma Hep-2 cells cultivated in the presence of different concentrations of sample for 48 h. IHe was biocompatible in the range of concentrations 2-200 mu g/mL, in NCTC cell culture. The compound showed cell cytotoxicity in the concentration range of 100-400 mu g/mL, in Hep-2 cell culture, revealing its antitumor activity. These results demonstrated the possible use of hederagenin isolated from H. helix extract as an antitumor agent.

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The aim of this study was to improve the bovine colostrum biological function through fermentation with kefir grains enhanced with selected yeasts, for developing new nutraceutical and cosmeceutical products. It was found that fermentations with co-culture of 2.5 g% artisanal kefir grains and selected yeast strains (10(6) CFU/100 mL) increased the functional quality of the fermented products compared to the product obtained only with kefir grains. Fresh fermented products obtained with a consortium based on kefir grains and Candida lipolytica MIUG D67 demonstrated an increased antioxidant activity of 2.69 mM Trolox Equivalent/g, after 48 h of fermentation. Instead, peptide fractions with MW<10 kDa isolated by membrane filtration from lyophilized fermented products, based on colostrum fermentation with kefir grains enhanced with Candida lipolytica MIUG D99 starter, presented markedly increase in vitro of ABTS radical scavenging activity, similar to a concentration of 2 nM captopril. These results indicated their possible application in enhance of the quality of the fermented products in order to increase the postbiotic composition with functional impact in vivo.

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Novel L-Arginine-Dextran70 based-silver nanoparticles (SNPs) (SNPs(Arg)), functionalized with Riboflavin (RF) and Human Serum Albumin (HSA) were characterized by UV-Vis absorption, Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), fluorescence and circular dichroism spectroscopy, chemiluminescence and Neutral red assays. TEM analysis showed the formed faceted particles, large clumps/fused aggregates, nano featured with the mean particle size of 41.60 nm. Chemiluminescence and Neutral red assays for in vitro antioxidant and cytotoxic activities of the SNPs(Arg)/RF/HSA systems have been studied. It was pointed out that SNPs(Arg) functionalized with RF and HSA resulted in a bio-nanosystem which leads to a high activity against oxygen free radicals, altered viability, morphology, apoptotic bodies and decreased cell density of L929 fibroblast cells. Results are relevant for understanding the redox properties of RF in the case of biological applications and especially for RF containing drugs.

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Silver nanoparticles (AgNP) suspensions were biosynthesized by silver ions reduction in the presence of collagen, a nontoxic, organic polymer, intending to improve their medical use in periodontitis treatment. Spectrophotometric measurements showed a time- and concentration-dependent increase of AgNP formation in each suspension variant. Transmission electron microscopy revealed spherical morphology of AgNP in collagen and their mean diameter size was around 30 nm. The particle size distribution and zeta potential values of AgNP in collagen were determined by dynamic light scattering measurements. The surface charge of AgNP in collagen was positive, while commercial AgNP stabilized in citrate had negative surface charge. In vitro cytotoxicity testing of AgNP in collagen showed that they were biocompatible with human gingival fibroblasts in a wider range of concentrations than commercial nanoparticles. The antibacterial activity of AgNP in collagen against two pathogenic strains present in the periodontal pocket was dose-dependent and higher than that of AgNP in citrate. All these results demonstrated that AgNP prepared in collagen gel had improved properties, like small diameter, positive surface charge, high biocompatibility in human gingival fibroblasts, efficiency against bacterial growth and, thus, better therapeutic potential in periodontal disease treatment.

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The aim of this study was to develop three-dimensional porous composites of collagen (Col) incorporating polyphenolic-rich wormwood extract and to investigate their interaction with human skin cells, in order to optimize wound healing treatments. The scaffolds' ultrastructure was observed by scanning electron microscopy, and biodegradability and bioactive compounds release were investigated in physiologic environment. Interaction of composites in direct and indirect contact with human skin cells was evaluated using two in vitro experimental models. ColWE scaffolds presented high porosity, swelling degree, and increased stability against enzymatic degradation, compared to Col scaffold. Composite scaffolds incorporating higher quantities of wormwood extract allowed better control of polyphenolics release. ColWE 0.5 variant favored the attachment and proliferation of human dermal fibroblasts and keratinocyte cells. In addition, the composite scaffold stimulated the synthesis of skin extracellular matrix components. All these results demonstrated that ColWE composites with improved physico-chemical and biological properties could be used in advanced wound healing applications.

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Atorvastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, is known to exert lipid-lowering, but also anti-inflammatory effects in extra-arterial locations. In order to avoid its toxicity associated with long-term oral treatment, in this study we have proposed novel lipid nanostructures containing atorvastatin to improve its efficiency and bioavailability after local application in periodontitis inflammation therapy. The physico-chemical characterization of the nanostructures was performed using dynamic light scattering technique and morphological observations were made by light microscopy. The encapsulation efficiency was determined by high performance liquid chromatography analysis of loaded atorvastatin. In vitro cytotoxicity and anti-inflammatory activity were evaluated in human premonocytic THP-1 cell line and a model of lipopolysaccharide-induced inflammation in macrophages, respectively. The results showed that the population of atorvastatin lipid nanostructures presented a mean diameter of 178 nm and a good homogeneity after sonication and extrusion treatments applying, as indicated by the low polydispersity index of 0.223. The efficiency of atorvastatin encapsulation was high (87.3%) and the nanostructures cytotoxicity was reduced for lipid concentrations ranging from 50 mu M to 500 mu M. Experiments in THP-1 cells differentiated to macrophages demonstrated that atorvastatin liposomal formulation led to a higher inhibition of lipopolysaccharide-induced proinflammatory cytokines (interleukin 6, tumor necrosis factor alpha and interleukin 8) release, compared to free drug. In conclusion, atorvastatin lipid nanostructures could be used to develop an efficient local treatment of periodontitis inflammation.

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Cytological responses in different organs of sentinel organisms have proven to be useful tools for characterizing the health status of those organisms and assessing the impact of environmental contaminants. Our study shows that nickel (II) accumulated in both germ cells (oogonia and developing oocytes) and somatic cells (muscle cells, follicle cells) in the Astacus leptodactylus ovary. Muscle cells from ovarian wall show disorganization and the disruption of cytoplasmic microtubules and pyknosis of the cell nucleus. Follicle cells, both those that surround the developing oocytes and also those that are not associated with the oocytes contained within the cytoplasm vacuoles of different sizes, degenerated mitochondria, myelin bodies, disorganized microtubules, and pyknotic nuclei. The most evident pathological phenomenon was the alteration and disorganization of the basal matrix, which separates the ovarian interstitium from ovarian follicles compartment. Exposure to nickel induces cytoplasmic vacuolation in oogonia and developing oocytes, structural alteration of the developing yolk granules and condensation of the nucleoli. Ultrastructural autometallography has shown grains of silver-enhanced nickel inside the cytoplasm of the muscle cells with altered morphology, including the cytoplasm, nucleus, and basal matrix of the follicle cells, and in intracisternal granules and developing yolk granules of the oocytes.

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The work aims to simulate in vitro, the antioxidant activity of riboflavin (RF) (Vitamin B-2) in Polyethylene Glycols (PEGs) (Tween20 and Myrj52)/Bovine Serum Albumin (BSA) systems, using the chemiluminescent system luminol-hydrogen peroxide, in alkaline solution, Tris-HCl buffer, pH 8.5. The tested concentrations were 2-20 mu M for RF and 0.06 to 0.6% for PEGs. It was found that 0.12% PEGs enhance the antioxidant activity of RF to higher and lower values, according to their molecular structure, Tween20 > Myrj52. RF has a pro-oxidant effect in the presence of BSA, while in the PEG/BSA systems, its antioxidant activity increases up to similar to 20%; a cross-linking of PEG to RF in the presence of BSA is considered. Additionally, studies by fluorescence spectroscopy on RF embedded in Tween20/BSA system-enhanced Tyrosine fluorescence contribution. In vitro cytotoxicity evaluation of RF in PEG/BSA systems was performed by Neutral Red assay and by monitoring lactate dehydrogenase release. PEG/BSA system offers great promise for enhancement of the RF antioxidant activity and biocompatibility, maintaining the integrity of the BSA, facts which are useful in the oxidative stress and drug delivery processes.

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The synthesis and physicochemical characterization of riboflavin (RF) loaded Myrj52-silver nanoparticles (SNPs) were performed and their cytotoxic properties were evaluated. Transmission electron microscopy analysis showed the formation of colloidal spherical SNPs with an average size of similar to 12 nm. The structure, stability, dynamics and conformation of human serum albumin (HSA) binding RF on SNPs have been studied. The influence of RF on the secondary structure of HSA in the presence of SNPs showed a predominant alpha-helix structure (61.7%). No changes induced by RF binding to HSA were observed. The cytotoxicity of RF and RF-HSA loaded Myrj52-SNPs was evaluated in vitro using the Neutral Red assay and cell morphology observations in a culture of L929 fibroblast cells. The results have relevance with regard to the RF loaded Myrj52-SNP formulation for pharmaceuticals.

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This study has been carried out to investigate a new method to improve metallic implant bioactivity for osseointegration by producing a calcium phosphate (Ca-P) surface layer using an immersion process in the Simulated Body Fluid (SBF) of Polypyrrole (PPy) and Polypyrrole/poly(sodium-4styrensulfonate) (NaPSS) conductive hybrid polymers electrochemically synthesized on Ti6A17Nb alloy. As formed PPy/Ca-P and PPy/ PSS-/Ca-P films were characterized electrochemically by Cyclic Voltammetry (CV), Tafel plots and spectroscopically using FT-IR technique. Also, in vitro cytotoxicity of these new organic/inorganic hybrids films was evaluated by yellow 3- (4,5-dimethylthiazolyI-2)-2,5-diphenyltetrazolium bromide (MTT) assay after cultivation in a primary culture of osteoblast cells. The PPy/Ca-P hybrid film showed the best electrochemical stability and the highest value of cell viability.

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Current procedures used for skin injury reepithelization have yet to improve. At present, stem cell-based therapies provide great potential in repairing different damaged tissues due to the multipotent character of these cells. This study aimed to investigate the in vitro differentiation capacity of human adipose-derived stem cells (ASCs) into epidermal cells and to evaluate their interaction with HaCaT keratinocytes in coculture experimental models that mimicked the living environment of human skin. The mesenchymal phenotype of isolated stem cells was indicated by their spindle-shaped morphology and the expression of specific surface markers CD73, CD90, and CD105. After 21 days of cultivation in specific induction medium, the epidermal keratinocyte phenotype of differentiated ASCs was demonstrated by the expression of cytokeratin 19 and involucrin markers, at both the protein and gene level. Significant (P < 0.05) proliferation of ASCs and HaCaT cells was recorded by an MTT assay in a Transwell system coculture as compared with control cells. Flow cytometry of HaCaT-ASC direct coculture showed a significant (P < 0.05) increase in DNA content in the G2/M and S phases and a decrease in the G0/G1 phase. All these data demonstrated that ASCs could be useful in future cell-based therapies for skin wound healing.

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Chondroitin-4 sulfate (CS4) is the main glycosaminoglycan extracted from bovine trachea. CS4 play an important role in osteoarthritis treatment, anticoagulant activity, reduces the degradation of cartilage matrix components, reduces necrosis and apoptosis of chondrocytes and reduces the activity of collagenase. Chondroitin sulfate is also responsible for proteoglycans degradation. Chondroitin sulfate can bind calcium ions with different affinities, depending on their sulfation position. The purpose of this study was to determine the structural properties and the influence of Ca2+ cations. We carried out measurements on CS4 solutions and mixtures of liquid CS4 with Ca2+ by Small-Angle Neutron Scattering (SANS). CS4 have a mass fractal behavior and the addition of a salt (CaCl2) in CS4 solutions generates the appearance of a correlation peak due to local ordering between adjacent chains with inter-chain distances between 483 angstrom and 233 angstrom for a calcium concentration of 0.01% w/w.

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Polymeric nanoparticles (NPs) are known to facilitate intracellular uptake of drugs to improve their efficacy, with minimum bioreactivity. The goal of this study was to assess cellular uptake and trafficking of PLGA NPs and chitosan (Chi)-covered PLGA NPs in Madin-Darby bovine kidney (MDBK) and human colorectal adenocarcinoma (Colo 205) cells. Both PLGA and Chi-PLGA NPs were not cytotoxic to the studied cells at concentrations up to 2500 g/mL. The positive charge conferred by the chitosan deposition on the PLGA NPs improved NPs uptake by MDBK cells. In this cell line, Chi-PLGA NPs colocalized partially with early endosomes compartment and showed a more consistent perinuclear localization than PLGA NPs. Kinetic uptake of PLGA NPs by Colo 205 was slower than that by MDBK cells, detected only at 24 h, exceeding that of Chi-PLGA NPs. This study offers new insights on NP interaction with target cells supporting the use of NPs as novel nutraceuticals/drug delivery systems in metabolic disorders or cancer therapy. (c) 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 3599-3611, 2015.

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The aim of this work was to characterize the physico-chemical properties of 3-hydroxyflavone (3-HF) in a silver nanoparticles complex (SNPs) using UV-vis and Fluorescence spectroscopy, Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM) analysis. One also evaluated its effect on the cell viability and morphology of L929 mouse fibroblast cells in vitro. The contribution of the carrier protein, Bovine Serum Albumin (BSA) to 3-HF properties has also been investigated. 3-HF in BSA/SNPs systems presented no cytotoxic effect in L929 mouse fibroblast cells at any of the tested concentrations. The results are discussed with relevance to the oxidative stress process.

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Several plant products are used as antioxidant agents to treat inflammation-related disorders. In recent years, encapsulation of biologic active compounds in lipid vesicles was shown to improve their bioavailability and transdermal delivery. The aim of this study was to prepare two arnica extracts of polyphenols (Pf) and polysaccharides (Pz) and their liposomal formulations (L-Pf, L-Pz) and to characterize their antioxidant and anti-inflammatory effect. Cytocompatible concentrations of Pf (50 mu g/ml), Pz (0.5 mu g/ml), L-Pf and L-Pz were tested for cytoprotective and anti-inflammatory activity in a model of hydrogen peroxide-stressed fibroblast cell culture by assessment of lactate dehydrogenase activity, cell morphology and pro-inflammatory cytokines production. The results demonstrated that L-Pf and L-Pz protected better the cell membrane against oxidative damage and had significantly (p<0.05) higher anti-inflammatory activity compared to their non-encapsulated forms. All these findings showed that the liposomal formulations of arnica extracts could be useful in topic treatment of inflammatory skin disorders.

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The aim of this paper was to assess cyto- and genotoxic effects of a lipophyle extract of pelloidic mud (LE) from Techirghiol Lake, Romania, using two in vitro tests: cell viability determination in a mice fibroblasts culture (NCTC, clone L 929) and Triticum assay. The extract contains a mixture of saturated and unsaturated hidrocarbonated compounds with carbonilic and carboxylic groups. Cytotoxic effect of LE, in a dilution ranging between 0.025- 1 g/mL, on the mice fibroblasts culture was assessed by neutral red (NR) test after 24 and 48 h of cultivation according to ISO 10993-5:2003. Cell viability was calculated by comparison with the cell culture control considered to be 100% viable cells, at each period of time. The morphological observations were done on culture plates after the cultured cells were fixed in methanol and Giemsa stained. In Triticum assay we used two concentrations of LE in alcoholic solutions (0.025 g/mL and 0.045 g/mL). The Triticum seeds were preliminary imbued in water, and then they were treated for 6, 12 and 24 hours in LE solutions. The control group was treated with tap water. In the end of the experiment the harvested root tips were prepared according to Feulgen's squash technique using Schiff reagent. The cytotoxic effects of LE were investigated by calculating the mitotic index and also through the analysis of chromosomes alterations during the mitosis. In mice fibroblasts culture the LE expressed a cytotoxic effect only in higher amounts than 0.066 g/mL. In lower concentrations of LE, the cells had 95% viability and there were no morphological changes, after 48 h of cultivation. Triticum assay showed that the powerful effect on the cell division was in 0.025 g/mL LE after 12 or 24 hours of treatment. It was observed a rise of mitotic index and a small number of chromosomal aberrations in all variants. Because the studied concentrations of LE on the seeds of Triticum aestivum were smaller than 0.066 g/mL, we can notice that LE solutions had cellular regeneration effects and also cell metabolism stimulating. As conclusions: LE was not cytotoxic in the range of concentration 0-0.066 g/mL and can be used in cosmetic products. The information given from the two assays correlated each other and offered a better image concerning the toxic effects of LE. The two methods could be used together in the future studies as alternative methods for toxicity assay.

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Smart drug delivery systems with controllable properties play an important role in targeted therapy and tissue regeneration. The aim of our study was the preparation and in vitro evaluation of a collagen (Col) matrix embedding a liposomal formulation of chondroitin sulfate (L-CS) for the treatment of inflammatory disorders. Structural studies using Oil Red O specific staining for lipids and scanning electron microscopy showed an alveolar network of nanosized Col fibrils decorated with deposits of L-CS at both periphery and inner of the matrix. The porosity and density of Col-L-CS matrix were similar to those of Col matrix, while its mean pore size and biodegradability had significantly higher and lower values (P < 0.05), respectively. In vitro cytotoxicity assays showed that the matrix system induced high cell viability and stimulated cell metabolism in L929 fibroblast cell culture. Light and electron micrographs of the cell-matrix construct showed that cells clustered into the porous structure at 72 h of cultivation. In vitro diffusion test indicated that the quantity of released CS was significantly lower (P < 0.05) after embedment of L-CS within Col matrix. All these results indicated that the biocompatible and biodegradable Col-L-CS matrix might be a promising delivery system for local treatment of inflamed site.

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Liposomes have the capacity to be used as efficient, biodegradable and nontoxic carriers of bioactive molecules and are able to better control their delivery at the site of interest. The objective of this study was to obtain and characterize an appropriate liposomal formulation of the bioactive molecule chondroitin sulfate (CS) for its use in the local treatment of inflammatory and degenerative disorders, specifically osteoarthritis (OA). Empty liposomes (L) and CS-entrapping liposomes (L-CS) were prepared by thin film hydration method followed by sonication and extrusion. They were characterized in terms of size, polydispersity index and zeta-potential by dynamic light scattering (DLS) and morphology by transmission electron microscopy. The effect of L-CS formulation on viability and morphology of mouse fibroblast cells and its biologic activity in hydrogen peroxide-stimulated cells were compared to those of L, non-encapsulated CS and a mixture of L and CS (L CS). Our results demonstrated a high biocompatibility of L-CS and a more efficient cell protection against oxidative damage using L-CS treatment than CS or L + CS treatment. Also, L-CS exhibited a higher anti-inflammatory activity than CS in stimulated cells by reducing the level of IL-8 and TNF-alpha, proinflammatory cytokines. The overall results suggest that the delivery of CS in liposomal formulation could improve its therapeutic potential in intra-articular treatment of OA.

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Background: Arnica montana L. and Artemisia absinthium L. (Asteraceae) are medicinal plants native to temperate regions of Europe, including Romania, traditionally used for treatment of skin wounds, bruises and contusions. In the present study, A. montana and A. absinthium ethanolic extracts were evaluated for their chemical composition, antioxidant activity and protective effect against H2O2-induced oxidative stress in a mouse fibroblast-like NCTC cell line. Results: A. absinthium extract showed a higher antioxidant capacity than A. montana extract as Trolox equivalent antioxidant capacity, Oxygen radical absorbance capacity and 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging activity, in correlation with its flavonoids and phenolic acids content. Both plant extracts had significant effects on the growth of NCTC cells in the range of 10-100 mg/L A. montana and 10-500 mg/L A. absinthium. They also protected fibroblast cells against hydrogen peroxide-induced oxidative damage, at the same doses. The best protection was observed in cell pre-treatment with 10 mg/L A. montana and 10-300 mg/L A. absinthium, respectively, as determined by Neutral red and lactate dehydrogenase assays. In addition, cell pre-treatment with plant extracts, at these concentrations, prevented morphological changes induced by hydrogen peroxide. Flow-cytometry analysis showed that pre-treatment with A. montana and A. absinthium extracts restored the proportion of cells in each phase of the cell cycle. Conclusions: A. montana and A. absinthium extracts, rich in flavonoids and phenolic acids, showed a good antioxidant activity and cytoprotective effect against oxidative damage in fibroblast-like cells. These results provide scientific support for the traditional use of A. montana and A. absinthium in treatment of skin disorders.

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The aim of this study was the quantitative determination of total phenolic and flavonoid content for five ethanolic plant extracts (Urtica dioica, Artemisia absinthium, Arnica montana, Achillea millefolium and Helleborus purpurascens). Also, their antioxidant activity was evaluated by Oxygen Radical Absorbance Capacity (ORAC) and Trolox Equivalent Antioxidative Capacity (TEAC) assays. All the studied extracts showed a higher antioxidant activity than Trolox, used as standard. The values of antioxidant activity determined by both methods increased in the following order: H. purpurascens, U. dioica, A. montana, A. millefolium, A. absinthium. The relationship between the total phenolic and flavonoid content of plant extracts and their antioxidant activity was also studied. The obtained results showed that A. absinthium and A. millefolium extracts, which contained the largest amount of phenolic and flavonoid compounds exhibited the highest level of total antioxidant capacity. Our in vitro assays indicate that the studied plant extracts are a significant source of natural antioxidants, which might be helpful in preventing the diseases caused by oxidative stress.

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Of great interest in developing artificial bone is the incorporation of magnesium (Mg) ions into the ceramic lattice in order to improve the physico-chemical and structural properties of the material and to increase its morphological affinity towards newly formed osseous tissue. In the present study, we evaluated the morphological and biological properties of composite scaffolds fabricated by mixing a nanopowder of Mg-substituted beta-tricalcium phosphate with collagen type I in two dry weight ratios (variant I and II). We used biochemical methods, and electron and light microscopy to investigate their porosity, biodegradability and morphology. Osteoblast cell culture behavior in the presence of nanocomposite variants was also examined. Variant I scaffold presented a higher percentage of cross-links and a better resistance to collagenase degradation compared to variant II scaffold. Their porosity did not vary significantly. Osteoblasts cultivated in the presence of nanocomposite scaffolds for 72 h exhibited good cell viability and a normal morphology. When osteoblasts were injected into the scaffolds, a slightly higher proportion of adhered cells were observed for Mg-substituted samples after 7 days of cultivation. All these results showed that Mg-containing porous composite scaffolds had controlled degradation, allowed osteoblast proliferation and adhesion and are good candidates for bone repair.

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The aim of this study was to develop two new variants of porous composites based on collogen-chondroitin sulfate-hydroxyapatite (COL-CS-HA) mixtures. Electron microscopy examination showed that the composites had a microporous structure, with HA deposits non-homogeneously disposed on COL fibrous bundles. Their porosity was higher than 90 % and the biodegradation in the presence of collagenase was reduced after UV treatment of the scaffolds. Composite biocompatibility was evaluated by MTT assay and light microscopy after cultivation in a human osteoblast primary culture. All COL-based materials showed a good in vitro biocompatibility, but COL-CS-HA composites presented better cell proliferation and adhesion than COL material. These porous composites demonstrate potential for future application as cell scaffolds in bone tissue engineering.

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The aim of this paper was the isolation and purification of medical interest polysaccharides from the European mistletoe (Viscum album L.) and their chemical and biological characterization in view of the usefulness for the regeneration of dermal tissue wounds. Four fractions (A1-A4) were obtained by ethanol precipitation of the polysaccharide aqueous total extract (PZT). The fraction A2 was the richest in hexoses (42.12%) and was purified by ion-exchange chromatography, resulting six fractions (B1-B6). The chemical composition of the purified fractions showed that B3 had the highest content in hexoses (30.06%) and uronic acids (23.74%). The gelatin-zymography analysis of the proteinases secreted by the dermal fibroblasts in the presence of A2 and B3 samples has demonstrated that, at a concentration of 100 mu g/ml, they didn't affect the cellular metabolism. The spectrophotometric method used to study the influence of purified polysaccharides on cell viabillity showed that the tested fractions were not toxic. In conclusion, the selected polysaccharide fractions, A2 and B3, can be used as active compounds in the composition of bioproducts for the regeneration of injured dermal tissue.

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The aim of this study was to prepare 4 new composite biomaterials based on polyurethane (PU) blended with different mixtures of collagen (COL), elastin (EL) and glycosaminoglycans (GAG). Bioactivated polymeric materials were structurally characterized by light and electron microscopy and their biodegradability and in vitro biocompatibility were comparatively assessed. The biomaterials presented smooth surfaces and the porosity decreased when natural polymers were added. All polymeric blend variants allowed cell proliferation and adhesion, with a more extensive growth on PU-COL variant. In conclusion, it was demonstrated that these new composite materials were biocompatible and good candidates for medical device fabrication.

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The aim of this study was to compare the protective effect of a green tea (Camellia sinensis) extract (GTE) and mixtures of GTE with collagen (COL) (GTE-COL I-V) against ultraviolet (UV) radiation using a primary culture of human dermal fibroblasts. Concentrations of GTE up to 25 mu g/ml had a significant positive effect on dermal fibroblast proliferation, spectrophotometrically assayed by the MTT test. However, concentrations of GTE higher than 25 mu g/ml, added in the culture medium, induced a cytotoxic effect on dermal fibroblasts. Similar results were found after UV-irradiation, when cells were cultivated in presence of the same concentrations of GTE. On the contrary, the fibroblast growth rate was similar or higher than the control, when cells were seeded on GTE-COL mixtures, even for the variants containing 50 mu g/ml and, respectively, 100 mu g/ml GTE. These observations were found both before and after cell irradiation. Cell adhesion data were in agreement with these results. Microscopical examination of the cells showed maintenance of the normal fibroblast phenotype, in the presence of all GTE-COL mixtures, before and after irradiation. All these data suggest that the tested GTE-COL materials could be efficient agents for skin protection against UV radiation.