Abstract

The extraction of bio-compounds from medicinal plants provides opportunities for using the plant extract for health benefits. Rosa canina L. is considered a natural superfood, and the valorization of its active compounds requires an extraction technique that ensures a suitable extraction yield while preserving the compounds' activity. In our study, infrared laser irradiation (IRLIR) technology was used for the first time in the bioactive compound's extraction from Rosa canina L. Different solvents (water-ethanol, hexane-ethanol) and different extraction times were tested to obtain a high extraction yield. Chromatographic and spectrophotometry methods were used to monitor the profile of bioactive compounds and the antioxidant activity of the extracts. The results obtained for IRLIR were compared with those obtained by accelerated solvent extraction (ASE), an advanced extraction method. The IRLIR technology proved to be a more reliable analytical tool for the extraction of (+)-catechin, gallic acid, and lutein. In addition, a richer extract formula was obtained by IRLIR extraction with respect to ASE, with the IRLIR process ensuring a short extraction time, low volume of the extraction solvent, low energy consumption, and a less expensive device.

Abstract

Cost-effective chemosensors have become an indispensable tool for sustainable monitoring in food safety and processing, where there is an urgent need for affordable, efficient, and real-time analytical solutions. This review discusses recent advances in low-cost chemosensor technologies, highlighting developments in materials, miniaturization, and integration into portable and accessible platforms. The focus is on applications for detecting contaminants, monitoring quality, and ensuring safety in food production and processing. This review also addresses the challenges related to sensor sensitivity, selectivity, and operational stability and provides insights into future directions and the role of low-cost chemosensors in supporting sustainable practices in these important sectors.

Abstract

The identification of melatonin in grapes has led to the publication of numerous studies on melatonin in wines, and the aim of this study was to perform a systematic review and meta-analysis of published data on melatonin concentrations in wines. In this context, international databases such as Scopus, Web of Science and PubMed were searched for relevant articles (437) up to 29 March 2025. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used. A total of 15 studies from eight countries, involving various wine types and analytical methods, were included in the meta-analysis. Considerable analytical variation was observed across studies, and high-performance liquid chromatography (HPLC) coupled with either mass spectrometry (MS) or fluorescence (FL) detection was shown to be the most accurate and sensitive method for quantifying melatonin. The highest concentrations were found in Spanish red Tempranillo wine, Romanian white Noah wine, and Romanian ros & eacute; Lidia wine. Red wines, particularly those produced from Cabernet Sauvignon (CS) grapes, were the most frequently studied. The results of this work provide a clearer picture of melatonin levels in wine. Further research is needed to explore the implications of melatonin content in wine for human health and the wine industry.

Abstract

A nitrogen-doped nanocrystalline electrochemical graphite sensor for the sensitive determination of oleuropein (OL) from extra virgin olive oils (EVOOs) is presented. The sensor was developed by the deposition of nanocrystalline graphite (NCG) using plasma-enhanced chemical vapour deposition (PECVD) on silicon wafers. Scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and X-ray diffraction analysis (XRD) were used to characterise the microstructure and morphology of the developed materials. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV) were used to investigate the electrochemical properties of the material and the performance of the sensor. The developed sensor showed good analytical performance against OL over a concentration range of 5.00-500.00 mu M, with a good detection limit of 3.93 mu M and a good sensitivity of 0.057 mu A mu M-1. The reproducibility of the electrochemical sensor was excellent, with a relative standard deviation (RSD) of 8.56% for seven measurements.

Abstract

The present study evaluated three green extraction methods, accelerated solvent extraction (ASE), ultrasound-assisted extraction (UAE), and laser irradiation extraction (LE), for the polyphenolic compounds and vitamin C extraction of Cornus mas L. and Crataegus monogyna fruit extracts. The polyphenols and vitamin C of extracts were quantified using HPLC-DAD, and the total phenolic content, flavonoid content, antioxidant activity (DPPH and reducing power), and antidiabetic activity were also studied. The antidiabetic activity was examined by the inhibition of alpha-amylase and alpha-glucosidase, and in vitro on a beta TC cell line (beta-TC-6). The results showed significant differentiation in the extraction yield between the methods used, with the ASE and LE presenting the highest values. The C. mas fruit extract obtained by ASE exhibited the best antioxidant activity, reaching an IC50 value of 31.82 +/- 0.10 mu g/mL in the DPPH assay and 33.95 +/- 0.20 mu g/mL in the reducing power assay. The C. mas fruit extracts obtained by ASE and LE also have the highest inhibitory activity on enzymes associated with metabolic disorders: alpha-amylase (IC50 = 0.44 +/- 0.02 mu g/mL for the extract obtained by ASE, and 0.11 +/- 0.01 mu g/mL for the extract obtained by LE at combined wavelengths of 1270 + 1550 nm) and alpha-glucosidase (IC50 of 77.1 +/- 3.1 mu g/mL for the extract obtained by ASE, and 98.2 +/- 4.7 mu g/mL for the extract obtained by LE at combined wavelengths of 1270 + 1550 nm). The evaluation of in vitro antidiabetic activity demonstrated that the treatment with C. mas and C. monogyna fruit extracts obtained using ASE stimulated the insulin secretion of beta-TC-6 cells, both under normal conditions and hyperglycemic conditions, as well. All results suggest that C. mas and C. monogyna fruit extracts are good sources of bioactive molecules with antioxidant and antidiabetic activity.

Abstract

In recent years, various studies have been carried out to increase the concentration of antioxidant active principles in red wines as a consequence of the effects of winemaking techniques on the polyphenols content. In this study, in order to obtain the most optimal wine in terms of content and efficiency of antioxidant activity, various winemaking technologies (punching-down and pumping-over maceration) were tried with diverse gradations (Feteasca Neagra and Cabernet Sauvignon wines) and the addition of different concentrations of melatonin in must. Suitable HPLC and spectrophotometric methods were used to follow the evolution of the antioxidant compounds from wines during aging (for 12 months). After comparing the acquired results, an increase was observed in the antioxidant compound concentrations, particularly in resveratrol (85%), peonidin-3-glucoside (100%) or cyanidin-3-glucoside (100%), and antioxidant activity (10-40%). The most enriched wine was obtained in the case of Feteasca Neagra by the addition of 0.5 mg of melatonin per 1 kg of must using the punch-down technology and, in the case of Cabernet Sauvignon, by the addition of 0.05 mg of melatonin per 1 kg of must using the pumping-over technique. This study can provide winemakers with an approach to enhance red wines with antioxidant compounds.

Abstract

The present study evaluated the antioxidant and antidiabetic properties of Medicago sativa and Solidago virgaurea extracts enriched in polyphenolic compounds. The extracts were obtained by accelerated solvent extraction (ASE) and laser irradiation. Then, microfiltration was used for purification, followed by nanofiltration used to concentrate the two extracts. The obtained extracts were analyzed to determine their antioxidant activity using DPPH radical scavenging and reducing power methods. The antidiabetic properties have been investigated in vitro on a murine insulinoma cell line (beta-TC-6) by the inhibition of alpha-amylase and alpha-glucosidase. M. sativa obtained by laser irradiation and concentrated by nanofiltration showed the highest DPPH center dot scavenging (EC50 = 105.2 +/- 1.1 mu g/mL) and reducing power activities (EC50 = 40.98 +/- 0.2 mu g/mL). M. sativa extracts had higher inhibition on alpha-amylase (IC50 = 23.9 +/- 1.2 mu g/mL for concentrated extract obtained after ASE, and 26.8 +/- 1.1), while S. virgaurea had the highest alpha-glucosidase inhibition (9.3 +/- 0.9 mu g/mL for concentrated extract obtained after ASE, and 8.6 +/- 0.7 mu g/mL for concentrated extract obtained after laser extraction). The obtained results after evaluating in vitro the antidiabetic activity showed that the treatment with M. sativa and S. virgaurea polyphenolic-rich extracts stimulated the insulin secretion of beta-TC-6 cells, both under normal conditions and under hyperglycemic conditions as well. This paper argues that M. sativa and S. virgaurea polyphenolic-rich extracts could be excellent natural sources with promising antidiabetic potential.

Abstract

In recent years, increased attention has been paid to the recovery of bioactive compounds from waste and by-products resulting from the agro-industrial sector and their valorization into new products, which can be used in the health, food, or agricultural industry, as innovative and sustainable approaches to waste management. In this work, two of these by-products resulting from the fruit-processing industry were used for the recovery of bioactive compounds (polyphenols), namely lingonberry pomace (Vaccinium vitis-idaea) and grape pomace (Vitis vinifera). Two green extraction techniques were employed to obtain hydroalcoholic extracts (solvent: 50% EtOH, 10% mass): ultrasound-assisted extraction (UAE) and accelerated solvent extraction (ASE). The extracts were subjected to micro- and ultrafiltration processes, and further analyzed to determine the bioactive compound content through spectrophotometric (UV-Vis) and chromatographic (HPLC-PDA) methods. Additionally, the extracts exhibited significant enzyme inhibition, particularly against alpha-amylase and beta-glucosidase, suggesting potential anti-diabetic properties. The extracts characteristics, polyphenolic content, antioxidant capacity and enzyme inhibitory ability, were statistically compared, and significant differences were found between the two extraction methods. The grape pomace concentrated extracts showed a pronounced inhibitory activity on both analyzed enzymes compared to the lingonberry pomace concentrated extracts, closer to the standard used; e.g., IC50 alpha-amylase = 0.30 +/- 0.01 mu g/mL (IC50 acarbose = 0.3 +/- 0.01 mu g/mL), IC50 alpha-glucosidase = 0.60 +/- 0.01 mu g/mL (IC50 acarbose = 0.57 +/- 0.02 mu g/mL). These findings highlight the potential of agro-industrial residues as bioactive compound resources, with their valorization through application in food, nutraceutical, or pharmaceutical industries therefore contributing to the sustainable development and promotion of circular economy principles with the recovery of valuable inputs from plant by-products.

Abstract

Abstract

Lately, there has been increased interest in the development of phytochemical alternatives for the prevention and treatment of type 2 diabetes, the alternatives that are able to reduce or prevent glucose absorption by inhibiting digestive enzymes. In this context, this study aims to analyze the inhibitory alpha-amylase and alpha-glucosidase activities of Artemisia abrotanum and Symphytum officinale polyphenolic compound-rich extracts obtained by membrane technologies (micro- and ultrafiltration). Polyphenols and flavones content, HPLC-MS polyphenolic compounds profiling, antioxidant activity, and cytotoxic potential of these herbs were determined. Major phenolic acid compounds were chlorogenic acid, ellagic acid, caffeic acid, and rosmarinic acid. The flavone content was higher in the case of A. abrotanum extracts, and the major compounds were rutin and umbelliferone. The polyphenolic-rich extract of A. abrotanum had the highest quantities of polyphenols, 977.75 mu g/mL, and flavones, 552.85 mu g/mL, as well as a pronounced alpha-amylase inhibitory activity (IC50 1881.21 +/- 1.8 mg/mL), a value close to acarbose inhibitory activity (IC50 1110.25 +/- 8.82 mg/mL) that was used as the control for both enzymes. The alpha-glucosidase inhibitory activity was higher for both herb extracts, more pronounced for S. officinale polyphenolic-rich extract (IC50 291.56 +/- 2.1 mg/mL), a value higher than that of acarbose (IC50 372.35 +/- 3.2 mg/mL). These plants show potential as a complementary therapy for type 2 diabetes management.

Abstract

In recent years, the wine industry has shown a considerable degree of interest in the occurrence of melatonin in wines. Sample pretreatment may be the most important step in trace analysis. Since wine is a complex matrix and melatonin is present in low amounts (ppb), an adequate extraction technique is required. In this study, the effect of several extraction methods, such as solid phase extraction (SPE), Quick, Easy, Cheap, Effective, Rugged, and Safe extraction (QuEChERS), and dispersive liquid-liquid micro-extraction (DLLME) was studied and the variable parameters that can arise throughout the extraction process were optimized to obtain the best results. A high-performance liquid chromatography with fluorescence detector (HPLC-FL) method was adapted and validated, including measurement uncertainty, for the analysis of melatonin in wines and to assess the efficiency of the extraction yield. After comparing the acquired results, the DLLME method was optimized. Extraction recoveries values ranging from 95 to 104% demonstrated that the approach may be successfully applied for the extraction and concentration (enrichment factor of almost eight) of melatonin in wine samples prior to HPLC-FL analysis. The first report of melatonin levels in Feteasca Neagra wines has been made. The data obtained for Cabernet Sauvignon revealed that the final levels of melatonin in the wines are dependent on the winemaking process.

Abstract

Until recently, the main antioxidant role among wine constituents was attributed to polyphenolic compounds, but once the presence of melatonin in wines was confirmed, an interesting new field of research opened up due to its possible synergistic effects with other antioxidants in the winemaking process, which may lead to a change in the profile of polyphenolic compounds and antioxidant activity. In order to investigate the evolution of active principles from the phenylpropanoid metabolism associated with the synergistic effects of melatonin, for the first time, a melatonin treatment was performed in the pre-stage of the different winemaking processes of Feteasca Neagra and Cabernet Sauvignon wines with different melatonin concentrations. After comparing the acquired results for the evolution of the polyphenolic compound profile and antioxidant activity of treated wines, we ascertained an increase in the antioxidant compound concentrations, especially in resveratrol, quercetin, and cyanidin-3-glucoside, directly proportional to the used melatonin concentration; an intensification in activity of PAL and C4H enzymes; and the modification in the expression of specific anthocyanin biosynthesis genes, especially UDP-D-glucose-flavonoid-3-O-glycosyltransferase. It was also shown that the application of melatonin in the pre-stage of the winemaking process can be successfully used to obtain red wines with increased antioxidant activity (almost 14%).

Abstract

Recently, there has been increased interest in the discovery of new natural herbal remedies for treating diabetes and inflammatory diseases. In this context, this work analyzed the antidiabetic and anti-inflammatory potential of Artemisia absinthium, Artemisia vulgaris and Trigonella foenum-graecum herbs, which have been studied less from this point of view. Therefore, extracts were prepared and processed using membrane technologies, micro- and ultrafiltration, to concentrate the biologically active principles. The polyphenol and flavone contents in the extracts were analyzed. The qualitative analysis of the polyphenolic compounds was performed via HPLC, identifying chlorogenic acid, rosmarinic acid and rutin in A. absinthium; chlorogenic acid, luteolin and rutin in A. vulgaris; and genistin in T. foenum-graecum. The antidiabetic activity of the extracts was analyzed by testing their ability to inhibit alpha-amylase and alpha-glucosidase, and the anti-inflammatory activity was analyzed by testing their ability to inhibit hyaluronidase and lipoxygenase. Thus, the concentrated extracts of T. foenum-graecum showed high inhibitory activity on a-amylase-IC50 = 3.22 +/- 0.3 mu g/mL-(compared with acarbose-IC50 = 3.5 +/- 0.18 mu g/mL) and high inhibitory activity on LOX-IC50 = 19.69 +/- 0.52 mu g/mL (compared with all standards used). The concentrated extract of A. vulgaris showed increased alpha-amylase inhibition activity-IC50 = 8.57 +/- 2.31 mu g/mL-compared to acarbose IC50 = 3.5 +/- 0.18 mu g/mL. The concentrated extract of A. absinthium showed pronounced LOX inhibition activity-IC50 = 19.71 +/- 0.79 mu g/mL-compared to ibuprofen-IC50 = 20.19 +/- 1.25 mu g/mL.

Abstract

This study presents the preparation of hybrid nanofiltration membranes based on poly(1,4-phenylene ether ether sulfone), polyacrylonitrile, poly(vinyl pyrrolidone), and SBA-15 mesoporous silica. Laser treatment of polymeric solutions to enhance the hydrophilicity and performance of membranes was investigated. The membranes' structure was characterized using scanning electron (SEM) and atomic force (AFM) microscopy and contact angle measurements. The addition of PAN in the casting solution produced significant changes in the membrane structure, from finger-like porous structures to sponge-like porous structures. Increased PAN concentration in the membrane composition enhanced the hydrophilicity of the membrane surface, which also accounted for the improvement in the antifouling capabilities. The permeation of apple pomace extract and the content of polyphenols and flavonoids were used to evaluate the efficacy of the hybrid membranes created. The results showed that the hybrid nanofiltration membranes based on PPEES/PAN/PVP/SBA-15: 15/5/1/1 and 17/3/1/1 exposed to laser for 5 min present a higher rejection coefficient to total polyphenols (78.6 +/- 0.7% and 97.8 +/- 0.9%, respectively) and flavonoids (28.7 +/- 0.2% and 50.3 +/- 0.4%, respectively) and are substantially better than a commercial membrane with MWCO 1000 Da or PPEES-PVP-based membrane.

Abstract

A simple and rapid differential pulse voltammetric (DPV) method using a single-use electroactivated pencil graphite electrode (PGE*) is proposed for the rapid screening of the total content of polyphenolics (TCP) with intermediate antioxidant power (AOP) in grapefruit peel and fresh juice. The results were compared and correlated with those provided by the HPLC-DAD-MS method. NG voltammetric behavior at PGE* was studied by cyclic voltammetry and an oxidation mechanism was suggested. The experimental conditions (type of PGE, electroactivation procedure, pH, nature and concentration of supporting electrolyte) for NG DPV determination were optimized. The NG peak current varied linearly with the concentration in the ranges 1.40 x 10(-6)-2.00 x 10(-5) and 2.00 x 10(-5)-1.40 x 10(-4) mol/L NG and a limit of detection (LoD) of 6.02 x 10(-7) mol/L NG was attained. The method repeatability expressed as relative standard deviation was 7.62% for the concentration level of 2.00 x 10(-6) mol/L NG. After accumulation for 240 s of NG at PGE* the LoD was lowered to 1.35 x 10(-7) mol/L NG, the linear range being 6.00 x 10(-7)-8.00 x 10(-6) mol/L NG. The developed electrochemical system was successfully tested on real samples and proved to be a cost-effective tool for the simple estimation of the TCP with intermediate AOP in citrus fruits.

Abstract

The nanofiltration composite membranes were obtained by incorporation of KIT-6 ordered mesoporous silica, before and after its functionalization with amine groups, into polyphenylene-ether-ether-sulfone (PPEES) matrix. The incorporation of silica nanoparticles into PPEES polymer matrix was evidenced by FTIR and UV-VIS spectroscopy. SEM images of the membranes cross-section and their surface topology, evidenced by AFM, showed a low effect of KIT-6 silica nanoparticles loading and functionalization. The performances of the obtained membranes were appraised in permeation of Chaenomeles japonica fruit extracts and the selective separation of phenolic acids and flavonoids. The obtained results proved that the PPEES with functionalized KIT-6 nanofiltration membrane, we have prepared, is suitable for the polyphenolic compound's concentration from the natural extracts.

Abstract

Resveratrol (RES) is a naturally occurring product with numerous biological activities. Despite its potential benefits, its use is limited due to its low aqueous stability and solubility in its native form. The porous sol-gel silica materials which are able to entrap different organic molecules represent new studied release carriers. The aim of this work was to generate a solid matrix to encapsulate RES ensuring protection, increased solubility and release in solutions. A non-toxic ingredient, namely beta-cyclodextrin (beta-CD), able to form inclusion complexes (ICs) with RES has been used. Ecological formulations have been processed by entrapping the RES containing ICs in silica matrices obtained from a silica colloidal sol by the aqueous route of the sol-gel method. Characterization methods (DSC, FTIR, UV-Vis, fluorescence studies, SEM) have evidenced the presence of RES-beta-CD inclusion complex in the silica powder, RES stability in the matrix and its release in aqueous and organic solutions, and the morphology of the carrier. An evaluation of the antioxidant activity of RES in the present formulation was performed by the chemiluminescence assay and RES release profile in aqueous solutions was obtained by HPLC-MS. The resulted materials can find applications in different domains. Graphic abstract

Abstract

This study investigated the potential of using the changes in polyphenol composition of red wine to enable a more comprehensive chemometric differentiation and suitable identification of authentication markers. Based on high performance liquid chromatography-mass spectrometry (HPLC-MS) data collected from Feteasca Neagra, Merlot, and Cabernet Sauvignon finished wines, phenolic profiles of relevant classes were investigated immediately after vinification (Stage 1), after three months (Stage 2) and six months (Stage 3) of storage, respectively. The data were subjected to multivariate analysis, and resulted in an initial vintage differentiation by principal component analysis (PCA), and variety grouping by canonical discriminant analysis (CDA). Based on polyphenol common biosynthesis route and on the PCA correlation matrix, additional descriptors were investigated. We observed that the inclusion of specific compositional ratios into the data matrix allowed for improved sample differentiation. We obtained simultaneous discrimination according to the considered oenological factors (variety, vintage, and geographical origin) as well as the respective clustering applied during the storage period. Subsequently, further discriminatory investigations to assign wine samples to their corresponding classes relied on partial least squares-discriminant analysis (PLS-DA); the classification models confirmed the clustering initially obtained by PCA. The benefits of the presented fingerprinting approach might justify its selection and warrant its potential as an applicable tool with improved authentication capabilities in red wines.

Abstract

Cancer is a multifactorial disease involving reprogramming of the gene function in normal cells through both genetic and epigenetic factors. The latter ones are essentially represented by chromatin remodeling factors as transcriptional control of gene expression at the nucleus level. Certain sets of tumor suppression genes controlling vital cell functions such as cell cycle, DNA repair, cell adhesion, and apoptosis are considered candidate genes for defining specific types of cancer. Their silencing may be achieved through somatic mutations or by epigenetic factors as DNA methylation and histone covalent modification. Two major DNA methylation patterns have been described in mammary gland tumors: genome hypomethylation and concomitant in situ hypermethylation in critical genes. Human mammary gland cancer has been studied through animal models, canine one offering opportunity to investigate the molecular aspects that better define the borderline between the primary inflammatory and tumor progression processes. In contrast, both humans and dogs share the same challenging environment. This work presents the preliminary results in a study of the transcriptional epigenetic markers identified in canine mammary glands during tumor development. Bisulfite mutagenesis based methylation-specific (MS)- PCR has been performed for the estimation of BRCA1, and BRCA2 gene promoter hyper-methylation profiles, concomitant to methylation sensible restriction of genomic DNA in order to estimate the global hypo-methylation status have been performed on 9 DNA samples obtained from clinically selected canine tumor tissues. Histone H3K9 trimethylated was stained by immunohistochemical methods (IHC) in normal and tumor tissues. The results are discussed through their crosstalk with DNA methylation dynamics in order to highlight the cancer initiation and progression processes in the context of heritability and the causes of sporadic cases.

Abstract

This study was focused on the phytochemical composition and biological activities of Anchusa officinalis and Melilotus officinalis polyphenolic-rich extracts obtained by nanofiltration. The high-performance liquid chromatography-mass spectrometry analysis showed that chlorogenic acid and rosmarinic acid were the main phenolic acids in both extracts. The main flavonoid compound from A. officinalis extracts is luteolin, whereas rutin and isoquercitrin are the main flavonoids in M. officinalis. M. officinalis polyphenolic-rich extract had the highest alpha-amylase (from hog pancreas) inhibitory activity (IC50 = 1.30 +/- 0.06 mu g/mL) and alpha-glucosidase (from Saccharomyces cerevisiae) inhibitory activity (IC50 = 92.18 +/- 1.92 mu g/mL). However, both extracts presented a significant alpha-glucosidase inhibitory activity. Furthermore, the hyaluronidase inhibition of polyphenolic-rich extracts also proved to be stronger (IC50 = 11.8 +/- 0.1 mu g/mL for M. officinalis and 36.5 +/- 0.2 mu g/mL for A. officinalis), but there was moderate or low lipoxygenase inhibition. The studies on the fibroblast cell line demonstrated that both A. officinalis and M. officinalis polyphenolic-rich extracts possess the cytotoxic effect at a concentration higher than 500 mu g/mL. The experimental data suggest that both extracts are promising candidates for the development of natural antidiabetic and anti-inflammatory food supplements.

Abstract

Because melatonin has strong antioxidant activity and wine is an alcoholic beverage of economic relevance, in the present work, the impact of some variable parameters that may occur in the winemaking process on the concentrations of melatonin and its precursors in Romanian wines was studied. Therefore, a sensitive and selective high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the simultaneous analysis of melatonin, serotonin, and L-tryptophan, and some method performance parameters including selectivity, detection limit, precision (by comparing with an alternative HPLC-FL method), accuracy, and robustness were validated. These determinations are significant and the final amounts of analytes are dependent on the microorganisms involved in the winemaking process, the grape variety, geographic regions of vineyards, and aging of wines. In the future, the method may be useful to increase the melatonin content and the antioxidant activity in wines by improved steps in the winemaking process, especially based on application of selected yeasts and improved fermentation conditions.

Abstract

This work proposes a novel method for determining the composition of mixtures of natural polyphenolic compounds: caffeic acid, gallic acid, ellagic acid, rosmarinic acid and quercitrin in plants. The method is based on the formation of colored spots by these compounds upon reaction with nano-oxides of Al2O3, ZnO, MgO, CeO2, TiO2 and MoO3 impregnated on filter paper and constituting a colorimetric sensor array (CSA). The image of the colored spots was analyzed and the intensity of the blue colour (BCI) component has shown maximum sensitivity in relation to phenolic compounds. The inverse of BCI was linearly correlated with the logarithm of the individual phenolic compound concentrations. Chemometric analysis by partial least squares regression (PLSR) of 1/BCI values for 24 synthetic mixtures of the 5 phenolic compounds measured with the colorimetric sensor array has demonstrated good correlation between the actual and the predicted concentration of quercitrin. For the other phenolic compounds, the colors measured with the colorimetric sensor array were greatly influenced by the concentrations of the other components in the mixture. The method was applied to the determination of quercitrin in medicinal teas and the results were compared to those obtained by HPLC. The discussion of the results emphasizes possible interferences in the tea samples. While further optimization of the colorimetric sensor array-based method appears necessary, tailored to the particular targeted application in real samples, the proposed method for polyphenol determination has advantages that include simplicity, low cost, and portability.

Abstract

Herein, several nitrogen-doped nano-crystalline graphite films (N-NCG) were prepared via plasma-enhanced chemical vapor deposition (PECVD); nano-crystalline graphite (NCG) was doped by adding ammonia gas during the PECVD growth. To develop electrochemical probes that can compete with glassy carbon (GC) electrodes for anthracene sensing, the N-NCG electrodes were systematically investigated using different techniques, including atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis, Raman spectroscopy, cyclic voltammetry (CV), and differential pulsed voltammetry (DPV). The obtained sensors were tested against anthracene in an acetonitrile/water mixture (80/20 v/v) wherein the N-NCG 3 and N-NCG 5 electrochemical probes showed analytical features comparable with those of the GC electrode. The best competitor for GC was N-NCG 3 in terms of linear working range (2.5 mu M-1 mM) and sensitivity (y = 6.09 x 10(-6)+ 1.21 x, r(2)= 0.9997 and y = 1.23 x 10(-5)+ 0.84 x, r(2)= 0.9959 for GC and N-NCG 3, respectively).

Abstract

Because melatonin has strong antioxidant activity and wine is an alcoholic beverage of economic relevance, in the present work, the impact of some variable parameters that may occur in the winemaking process on the concentrations of melatonin and its precursors in Romanian wines was studied. Therefore, a sensitive and selective high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the simultaneous analysis of melatonin, serotonin, and L-tryptophan, and some method performance parameters including selectivity, detection limit, precision (by comparing with an alternative HPLC-FL method), accuracy, and robustness were validated. These determinations are significant and the final amounts of analytes are dependent on the microorganisms involved in the winemaking process, the grape variety, geographic regions of vineyards, and aging of wines. In the future, the method may be useful to increase the melatonin content and the antioxidant activity in wines by improved steps in the winemaking process, especially based on application of selected yeasts and improved fermentation conditions. © 2020 American Chemical Society

Abstract

Abstract

Abstract

A thick nano-crystalline graphite film (NCG, similar to 350 nm) was grown on dielectric substrate (SiO2, similar to 110 nm) using plasma-enhanced chemical vapour deposition (PECVD) aiming the development of an electrochemical sensor for caffeic acid. The obtained sensor was characterised using several investigation techniques such as atomic force microscopy (AFM), X-ray diffraction (XRD), Raman spectroscopy, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The data evidenced the coexistence in the investigated sample of the nano-crystalline graphite/graphene domains, while the NCG sheet resistance (similar to 340 U/sq.) is matching well the value reported for few-layers graphene film, revealing for the nano-crystalline graphite film a better ordered graphene structure and an improved electrical conduction in the interconnected graphene domains. The sensor for caffeic acid, operating at an applied potential of +0.4 V vs. Hg/Hg2Cl2 reference electrode showed a linear working range comprised between 5.0 X 10(-5) and 1.0 X 10(-3) M, and very good capabilities against real samples analysis. The reproducibility of the developed sensor was assessed in the presence of 0.1mM caffeic acid and the relative standard deviation was 5.84% (n = 11). (c) 2019 Elsevier Ltd. All rights reserved.

Abstract

A Si wafer coated with a low temperature oxide (LTO) was used as substrate (Si/SiO2) during the deposition of a thick nano-crystalline graphite (NCG) film by means of plasma-enhanced chemical vapour deposition (PECVD) procedure. The process parameters, the atomic force (AFM) and scanning electron (SEM) micrographs, Raman spectrum and X-ray diffraction (XRD) pattern are herein illustrated. The as deposited NCG film was electrochemically pretreated (3 mA applied current, during 240 s, in 10 mM phosphate buffer saline (PBS) solution containing 0.1 M KCl, pH 7) and thereafter used as electrode for sensing the caffeic acid content in lyophilised berries and dried chokeberries in Nano-crystalline graphite film on SiO2: Electrochemistry and electro-analytical application [1]. (C) 2019 The Author(s). Published by Elsevier Inc.

Abstract

This study evaluated the biological activities of Eryngium planum and of Cnicus benedictus extracts enriched in polyphenols obtained by nanofiltration. The HPLC-MS analysis showed that E. planum contains mainly flavonoids, especially rutin, while in C. benedictus extracts show the high concentration of the phenolic acids, principally the chlorogenic acid and sinapic acid. Herein, there is the first report of ursolic acid, genistin, and isorhamnetin in E. planum and C. benedictus. C. benedictus polyphenolic-rich extract showed high scavenging activity (IC50=0.0081 mg/mL) comparable to that of standard compound (ascorbic acid) and a higher reducing power (IC50= 0.082 mg/mL), with IC50 having a significantly lower value than IC50 for ascorbic acid. Both extracts were nontoxic to NCTC cell line. Among the investigated herbs, E. planum polyphenolic-rich extract showed the highest inhibitory activities with the IC50 value of 31.3 g/mL for lipoxygenase and 24.6 g/mL for hyaluronidase. Both polyphenolic-rich extracts had a higher inhibitory effect on -amylase and -glucosidase than that of the acarbose. The synergistic effect of ursolic acid, rutin, chlorogenic acid, rosmarinic acid, genistin, and daidzein identified in polyphenolic-rich extracts could be mainly responsible for the pharmacological potentials of the studied extracts used in managing inflammation and diabetes.

Abstract

A thick nano-crystalline graphite film (NCG, ∼350 nm) was grown on dielectric substrate (SiO 2 , ∼110 nm) using plasma-enhanced chemical vapour deposition (PECVD) aiming the development of an electrochemical sensor for caffeic acid. The obtained sensor was characterised using several investigation techniques such as atomic force microscopy (AFM), X-ray diffraction (XRD), Raman spectroscopy, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The data evidenced the coexistence in the investigated sample of the nano-crystalline graphite/graphene domains, while the NCG sheet resistance (∼340 Ω/sq.) is matching well the value reported for few-layers graphene film, revealing for the nano-crystalline graphite film a better ordered graphene structure and an improved electrical conduction in the interconnected graphene domains. The sensor for caffeic acid, operating at an applied potential of +0.4 V vs. Hg/Hg 2 Cl 2 reference electrode showed a linear working range comprised between 5.0 × 10 −5 and 1.0 × 10 −3 M, and very good capabilities against real samples analysis. The reproducibility of the developed sensor was assessed in the presence of 0.1 mM caffeic acid and the relative standard deviation was 5.84% (n = 11). © 2019 Elsevier Ltd

Abstract

The electrochemical behaviour of the flavonoid naringenin (NGN) was investigated for the first time by cyclic voltammetry (CV), using a disposable electroactivated pencil graphite electrode (PGE*). In this electrochemical sensor, NGN is irreversibly oxidized, giving rise to two pH-dependent peaks due to mixed (diffusion- and adsorption-controlled) electrode processes involving the same number of electrons and protons, namely two and one, respectively. Exploiting these peaks, differential pulse voltammetry (DPV) and square wave voltammetry (SWV) at PGE* in 0.05 mol L-1 potassium hydrogen phthalate were applied for quantitative determination of NGN. The new proposed methods presented linear ranges covering more than three orders of magnitude (7.86 x 10(-8) to 1.82 x 10(-4) mol L-1 NGN for DPV and 7.50 x 10(-8) to 1.00 x 10(-4) mol L-1 NGN for SWV) and low limits of detection (LoD) and quantification (LoQ) (LoD = 3.06 x 10(-8) mol L-1, LoQ = 1.02 x 10(-7) mol L-1 NGN for DPV and LoD = 4.40 x 10(-8) mol L-1, LoQ = 1.11 x 10(-7) mol L-1 NGN for SWV), similar to or better than those reported in the literature. The developed voltammetric methods were applied with good results to determine the intermediate antioxidant power polyphenolics content expressed as mg naringenin equivalent per L grapefruit juice.

Abstract

It is well known that the secretion of melatonin begins after the first months of life and is necessary to be supplied through mother's milk or infant formula. It is also important to know the concentrations of compounds involved in the synthesis of melatonin in the pineal gland from the composition of infant formula. Therefore, an HPLC method with UV and fluorescence detection was developed which enables the simultaneous determination of melatonin, serotonin, L-tryptophan, and vitamins B-3 and B-6 in 30 min. The chromatographic method was validated in terms of selectivity, linearity range of the response (R > 0.9997), detection limit (0.0011-0.01 mg L-1), limit of quantitation, precision, accuracy, and robustness and has been proved that it may be used as a tool for evaluating these compounds in infant formulas and also in the manufacture of baby foods. The chromatographic method was applied for the quantification of analytes of interest and for the first time, it has proven the existence of melatonin (0.00045-0.00824 mg/g) and serotonin (0.00002-0.00056 mg/g) in infant formulas from birth onwards.

Abstract

The electrochemical behaviour of the flavonoid naringenin (NGN) was investigated for the first time by cyclic voltammetry (CV), using a disposable electroactivated pencil graphite electrode (PGE∗). In this electrochemical sensor, NGN is irreversibly oxidized, giving rise to two pH-dependent peaks due to mixed (diffusion- and adsorption-controlled) electrode processes involving the same number of electrons and protons, namely two and one, respectively. Exploiting these peaks, differential pulse voltammetry (DPV) and square wave voltammetry (SWV) at PGE∗ in 0.05 mol L -1 potassium hydrogen phthalate were applied for quantitative determination of NGN. The new proposed methods presented linear ranges covering more than three orders of magnitude (7.86 × 10 -8 to 1.82 × 10 -4 mol L -1 NGN for DPV and 7.50 × 10 -8 to 1.00 × 10 -4 mol L -1 NGN for SWV) and low limits of detection (LoD) and quantification (LoQ) (LoD = 3.06 × 10 -8 mol L -1 , LoQ = 1.02 × 10 -7 mol L -1 NGN for DPV and LoD = 4.40 × 10 -8 mol L -1 , LoQ = 1.11 × 10 -7 mol L -1 NGN for SWV), similar to or better than those reported in the literature. The developed voltammetric methods were applied with good results to determine the intermediate antioxidant power polyphenolics content expressed as mg naringenin equivalent per L grapefruit juice. © 2018 The Royal Society of Chemistry.

Abstract

In this study several investigations and tests were performed to determine the antioxidant activity and the acetylcholinesterase and tyrosinase inhibitory potential of Pulmonaria officinalis and Centarium umbellatum aqueous extracts (10% mass) and ethanolic extracts (10% mass and 70% ethanol), respectively. Moreover, for each type of the prepared extracts of P. officinalis and of C. umbellatum the content in the biologically active compounds – polyphenols, flavones and proanthocyanidins was determined. The antioxidant activity was assessed using two methods, namely the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and reducing power assay. The analyzed plant extracts showed a high acetylcholinesterase and tyrosinase inhibitory activity in the range of 72.24–94.24% (at the highest used dose – 3 mg/mL), 66.96% and 94.03% (at 3 mg/mL), respectively correlated with a high DPPH radical inhibition – 70.29–84.9% (at 3 mg/mL). These medicinal plants could provide a potential natural source of bioactive compounds and could be beneficial to the human health, especially in the neurodegenerative disorders and as sources of natural antioxidants in food industry. © 2016

Abstract

The goal of the present work was to study the influence of winemaking procedures and the effect of bottle-aging on the antioxidant activity and on the variation of low molecular weight phenolics of Feteasca Neagra and Negru Aromat red wine from the Valea Calugareasca vineyard, Romania. The free radical-scavenging activity was measured using the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical from bottles sampled every 3 months up to the 9th month. The results indicated that Negru Aromat obtained by classical maceration had the highest activity at 6th month. The highperformance liquid chromatography results showed that the most abundant low molecular weight phenolic compounds were catechin, (-)-epicatechin, gallic acid, malvidin, and peonidin 3-O-glucoside. For the phenolics, Feteasca Neagra prepared by classical maceration and Negru Aromat by run-off juice were the richest. For anthocyanidins, the Feteasca Neagra and Negru Aromat wine by classical maceration had the highest concentrations. These results suggest that classical maceration is the winemaking procedure of choice to obtain the highest quality wine from the Valea Calugareasca vineyard.

Abstract

Abstract

Abstract

The quality of red wines is given by phenolic compounds and anthocyanins and is associated with colour, taste and therapeutic effects on human health. This work aims to provide a detailed profile of phenolic compounds and anthocyanins that are found in five red wine samples from Dealu Mare-Valea Calugareasca region. The phenolic and anthocyanin profiles of the red wine samples were determined by high-performance liquid chromatography-photodiode array-mass spectrometry and matrix-assisted laser desorption/ionisation-time of flight, respectively. The results obtained showed that Feteasca Neagra had the highest content of phenolic compounds followed by Pinot Noir while the preponderant compound was gallic acid. Amongst anthocyanins, malvidin was found to be the major compound and the highest anthocyanin content was found also for Feteasca Neagra wine. A simple high-performance liquid chromatography-photodiode array-mass spectrometry method was developed, optimised and applied for the quantification of phenolic compounds in red wine samples from Dealu Mare-Valea Calugareasca region. In the same time, a rapid matrix-assisted laser desorption/ionisation-time of flight method that does not need sample preparation was applied for the identification of anthocyanins. Moreover, the phenolic and anthocyanin composition of red wines from Dealu Mare-Valea Calugareasca region is reported for the first time. The phenolic and anthocyanin profile determination will be beneficial for the Romanian winemakers to produce high-quality red wines.

Abstract

In the current work, ethanol and water extracts of Verbascum phlomoides and Solidago virgaureae were examined for their inhibitory effects against acetylcholinesterase and tyrosinase, as well as for their antioxidant activity. The antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and a reducing power assay. The total content of phenolics, flavonoids and proanthocyanidins, and the high-performance liquid chromatography profile of the main phenolic compounds were also determined. Generally, ethanol extracts showed the strongest antioxidant and enzyme inhibitory activities, both of which were related to the total phenolic content. The V. phlomoides ethanol extract showed the highest inhibitory activity against both acetylcholinesterase (IC50= 0.086 +/- 0.005 mg/mL) and tyrosinase (IC50= 0.109 +/- 0.092 mg/mL). These results reveal that V. phlomoides and S. virgaureae are potential sources of active metabolites with acetylcholinesterase and tyrosinase inhibitory effects. As a result they could be considered for dietary food supplements for preventing neurodegenerative diseases. (C) 2016 Elsevier GmbH. All rights reserved.

Abstract

The aim of this study was to investigate the antioxidant, anti-amylase and anti-glucosidase activities of polyphenolic-rich extracts from Betonica officinalis and Impatiens noli-tangere and to analyze their chemical composition by HPLC-MS. Hydro-alcoholic extracts of the two medicinal herbs were processed by microfiltration and ultrafiltration for concentrating the polyphenolic compounds. Phenolic acid, mainly chlorogenic acid and caffeic acid were the dominant compounds of B. officinalis extracts, while the extracts from L nolitangere contain mainly flavonoids, especially isoquercitrin. The polyphenolic-rich extract (retentate UF fraction) from B. officinalis exhibited the most potent DPPH radical scavenging and reducing power activities. The IC50 value of the alpha-amylase inhibitory effect was 4.20 +/- 0.30 mg/mL for the B. officinalis polyphenolic-rich extract, slightly higher than that of I. noli-tangere polyphenolic-rich extract of 4.01 +/- 0.25 mg/mL. The polyphenolic-rich extract from I. noli-tangere showed remarkable a-glucosidase inhibition activity (IC50 0.47 +/- 0.02 mg/mL), compared to the acarbose (IC50 0.38 +/- 0.02 mg/mL). However, I. noli-tangere extracts displayed a stronger inhibitory activity than B. officinalis extract fractions. Our study, for the first time, revealed the anti-diabetic potential of the B. officinalis and I. noli-tangere herbs. The results of this study could be helpful to develop medicinal preparations or functional foods for diabetes. (C) 2015 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

Abstract

Abstract

The optimization of an aptasensor with SPR detection allowed the determination of an allergen protein, lysozyme, with high accuracy, good sensitivity and a detection limit of 2.4 nM for spiked red and white wines. The interaction of lysozyme with specific phenolic compounds from wine was evidenced by circular dichroism and SPR. Quantitative recovery factors higher than 88% for wine lysozyme were achieved based on a sample pre-treatment procedure with high concentration of sodium chloride and Tween-20. This aptasensor is useful to monitor the lysozyme levels during winemaking. Also reported is a new chromatographic method based on size exclusion that provided a good separation of lysozyme from wine components, with a detection limit of 35 nM or 0.5 mu g/mL. (C) 2014 Elsevier B.V. All rights reserved.

Abstract

In this work a novel sensor array platform based on a dual carbon screen-printed electrode was developed for the simultaneous determination of chlorogenic acid and caffeine. One of the carbon working electrodes was modified with platinum nanoparticles, reduced graphene oxide and laccase (C-SPE/Pt-NPs/RGO/lacc-biosensor) for chlorogenic acid determination and the second carbon working electrodes was modified with reduced graphene oxide and Nafion (C-SPE/RGO/Nafion-sensor) for caffeine determination. Cyclic voltammetry was used to characterise and optimise the dual sensor array while chronoamperometry was used to investigate the bioelectrocatalytic response. The C-SPE/Pt-NPs/RGO/lacc for biosensing chlorogenic acid exhibited a sensitivity of 0.02 mu A mu M (1) and a detection limit of 2.67 mu M whereas the C-SPE/RGO/Nafion used for sensing caffeine has showed a sensitivity of 1.38 mu A mu M-1 and a detection limit of 0.22 mu M. The developed sensor array was used to determine these two major coffee bean compounds from real coffee samples. Due to its simplicity, feasibility and accessibility, the developed dual sensor array could represent the basis of a valuable analytical tool able to screen both chlorogenic acid and caffeine content from coffee samples offering important information about the phytochemical composition of the samples.

Abstract

Context: Eryngium planum, Geum urbanum and Cnicus benedictus plants are an endemic botanical from the Romanian used in folk medicine. Objective: The extracts from three Romanian medicinal plants were investigated for their possible neuroprotective potential. Materials and Methods: Within this study, in vitro neuroprotective activity of the extracts of E. planum, G. urbanum, and C. benedictus plants were investigated via inhibition of acetylcholinesterase (AChE) and tyrosinase (TYR). Total content of phenolics, flavonoids, and proanthocyanidins, high-performance liquid chromatography profile of the main phenolic compounds and antioxidant activity were also determined. Results: Among the tested extracts, the best inhibition of AChE (88.76 +/- 5.2%) and TYR (88.5 +/- 5.2%) was caused by C. benedictus ethanol (EtOH) extract. The G. urbanum extracts exerted remarkable scavenging effect against 2,2-diphenyl-1-picrylhydrazyl (IC 50, 7.8 +/- 0.5 mu g/mL aqueous extract, and IC50, 1.3 +/- 0.1 mu g/mL EtOH extract, respectively) and reducing power, whereas the EtOH extract of C. benedictus showed high scavenging activity (IC 50, 0.609 +/- 0.04 mg/mL), also. Conclusion: According to our knowledge, this is the first study that demonstrates in vitro neuroprotective effects of E. planum, G. urbanum and C. benedictus.

Abstract

The main objective of this study is to concentrate the antioxidant bioactive compounds from the hydroalcoholic extract of Phyllitis scolopendrium through the poly(1,4-phenylene ether ether sulfone) (PPEES) ultrafiltration membrane. The PPEES membrane was prepared using the phase inversion method. The total content of phenolics and flavonoids, HPLC profile of the main phenolic compounds, and antioxidant and anti-tyrosinase activities were also determined in the microfiltrate, permeate and concentrate. When the PPEES membrane is used the concentration of polyphenols and flavonoids is higher, reaching the retention index of 0.785 and of 0.683, respectively, than that measured in the case of processing the feed through the PSF membrane. PPEES membranes showed a higher concentration towards anti-tyrosinase compounds (71.9 +/- 4.3%), compared with the PSF membranes (58.7 +/- 2.9%). The obtained results proved that the PPEES membrane we have prepared is suitable for the bioactive compound's concentration from the herbal extracts. This could result in their wide application in the food and pharmaceutical industries.

Abstract

Medicinal plants represent an important source of active biological compounds that could be used for new drugs development. The present work aims the assessment of two Romanian medicinal plants that were not well studied Alchemilla vulgaris and Filipendula ulmaria with respect to their neuroprotective potentiality. The aqueous extracts (10% mass) and ethanolic extracts (10% mass and 70% (v/v) ethanol) of A. vulgaris and F. ulmaria were screened to evaluate their acetylcholinesterase and tyrosinase inhibitory effects as well as their antioxidant activity. The antioxidant activity was determined using two methods, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH) and reducing power assay. The total polyphenolic content determined in the tested compounds was between 88.00 and 112.33 mu g/mL, flavones between 360.00 and 862.00 mu g/mL and proanthocyanidins between 77.66 and 130.00 mu g/mL. The acetylcholinesterase inhibitory activity was determined to be between 77.03 and 98.39% (at the highest used dose -3 mg/mL), the tyrosinase inhibitory activity was found to be between 60.00 and 90.65% (at 3 mg/mL) and the DPPH radical inhibition between 73.90 and 93.49%. These findings support the use of these medicinal plants in the treatment of neurodegenerative disorders such as Parkinson, Alzheimer. (C) 2015 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

Abstract

The present work describes the development of an electrochemical method based on the use of 2,2'-diphenyl-1-picrylhidrazyl free radical (DPPH.) for the determination of the antiradical properties of several olive oils. Differential pulse voltammetry was used as measuring technique while the electrochemical process was recorded at a platinum screen-printed working electrode. The decrease in 2,2'-diphenyl-1-picrylhidrazyl peak current intensity was measured at a specific potential value of +160 mV vs. screen-printed pseudo-reference electrode, in the presence of alpha-, delta- and gamma-tocopherol and olive oil samples, respectively. The obtained results using differential pulse voltammetry, as detection technique for real samples analysis, showed a satisfactory agreement with those obtained by high-performance liquid chromatography coupled with fluorescence detection. The reported electrochemical method is rapid and easy to use, feasible and accessible to be used as an alternative to 2,2'-diphenyl-1-picrylhidrazyl spectrophotometric based method. (C) 2014 Elsevier Ltd. All rights reserved.

Abstract

Some plants collected (Mentha aquatica, Bidens tripartita and Ambrosia artemisiifolia) from an unusual habitat developed in recent years in Bucharest (the so-called Bucharest Delta) and the contents of polyphenolic compounds, short-chain organic acids and heavy metals, and radical scavenger activity, were determined. 12 polyphenolic compounds and 7 short-chain organic acids were quantified using high-performance liquid chromatography and capillary electrophoresis; Mentha aq. extracts presented the highest levels of rosmarinic acid (1.58 mg g(-1)) and ferulic acid (2.84 mg g(-1)) and Bidens extracts presented the highest concentrations of chlorogenic acid (0.44 mg g(-1)); the same extracts contain the most important levels of luteolin (0.52 mg g(-1)) or other flavonoids. All the heavy metals detected in the plants studied were found in very low levels (the highest was Pb(II) in Mentha aquatica, (12.84 +/- 0.48) mu g kg(-1)). The study sought to identify the active compounds and some contaminants in plants collected from the Bucharest Delta with the intention of eventual exploitation of the habitat and to enhance the knowledge of such human-modified ecosystems. (C) 2015 Institute of Chemistry, Slovak Academy of Sciences

Abstract

Some plants collected (Mentha aquatica, Bidens tripartita and Ambrosia artemisiifolia) from an unusual habitat developed in recent years in Bucharest (the so-called "Bucharest Delta") and the contents of polyphenolic compounds, short-chain organic acids and heavy metals, and radical scavenger activity, were determined. 12 polyphenolic compounds and 7 short-chain organic acids were quantified using high-performance liquid chromatography and capillary electrophoresis; Mentha aq. extracts presented the highest levels of rosmarinic acid (1.58 mg g-1) and ferulic acid (2.84 mg g-1) and Bidens extracts presented the highest concentrations of chlorogenic acid (0.44 mg g-1); the same extracts contain the most important levels of luteolin (0.52 mg g-1) or other flavonoids. All the heavy metals detected in the plants studied were found in very low levels (the highest was Pb(II) in Mentha aquatica, (12.84 ± 0.48) μg kg-1). The study sought to identify the active compounds and some contaminants in plants collected from the "Bucharest Delta" with the intention of eventual exploitation of the habitat and to enhance the knowledge of such human-modified ecosystems. © 2015 Institute of Chemistry, Slovak Academy of Sciences.

Abstract

Abstract

Abstract

The natural methyl donor group, S-adenosylmethionine and its product, S-adenosylhomocysteine play an important role in many biochemical reactions involving transmethylation reactions. These compounds can be used as biomarkers in incipient diagnosis of various pathological disorders therefore the validation of a suitable method to routinely analysis of these compounds is very important. In this paper, a high performance liquid chromatrography method for S-adenosylmethionine and S-adenosylhomocysteine measurement as fluorescent 1,N (6)-ethanoderivatives from biological samples was validated in terms of selectivity, linearity range of the response (R > 0.9993), detection limit (9 x 10(-9) and 4.4 x 10(-9) molL(-1)), the limit of quantitation (9.7 x 10(-9) and 5.7 x 10(-9) mol L-1), precision, trueness and robustness. The method for quantification simultaneous of these compounds is rapid, sensitive and precise and appropriate for clinical analysis.

Abstract

A fast and selective method based on high-performance liquid chromatography with diode array and atmospheric pressure chemical ionization-mass spectrometry detection (HPLC-DAD-APCI-MS) was developed and optimized to assess specific food samples content in carotenoids. Two compounds were chosen as significant carotenoids with respect to nutritional value, beta-carotene, and lycopene. The optimum conditions suitable for samples analysis were: a mobile phase of methanol: water (95: 5) (A) and acetonitrile: methylene chloride (90: 10) (B), with a gradient elution: 0-4 min 0% B, 4-7 min 20% B, 7-10 min 50% B, 0-10 min flow 0.1 mL/min, 10-30 min 90% B, 10-30 min flow 0.2 mL/min. Analytes were separated within 30 min on a C18 column and a diode array detection (450 nm for beta-carotene and 470 nm for lycopene). The linear dependence between peak area and concentration ranged from 5x10(-7) molL(-1) to 5x10(-5) molL(-1) (r=0.9998, n=9) for beta-carotene and respectively 7.5x10(-7) molL(-1) to 7.5x10(-5) molL(-1) (r=0.9986, n=5) for lycopene. The optimized method was used to quantify beta-carotene and lycopene in bakery products enriched with carotenoids devoted to the nutrition of aged population, method that could be standardized and used for bakery products quality control.

Abstract

Soilless cultures are nowadays an important tool for both (i) large scale synthesis of pharmaceutically active products, and for (ii) ex situ conservation of endemic and/or endangered plants that are also of horticultural importance. (i) Epilobium hirsutum explants were grown on both solid-and shaken liquid-medium, for multiplication and for greater biomass production, respectively. Secondary metabolites extracted from the biomass thus obtained were mainly polyphenols (galloylglucose and monomeric and dimeric ellagitannins), which are pharmaceutically important in prostate adenoma treatment, among others. Seedlings' dry biomass production increased from 1.5 g DW L-1 to 22 g DW L-1 after 15 days when nodes/inocula were grown on shaken liquid-medium, in light, and using different phytohormonal conditions. Secondary metabolites yield (polyphenols) of seedlings was equal to or higher (under some conditions) than for intact plants grown normally, in soil, under normal conditions. (ii) In vitro conservation on solid media resulted in a collection of 12 species that are endemic and/or endangered for Europe, and 7 species for Romania, respectively. Included in this collection are: Dianthus spiculifolius, D. nardiformis, D. henteri, D. glacialis subsp. gelidus, D. haematocalyx subsp. pindicola, D. seguieri, D. sternbergii, Achillea pyrenaica, Paradisea liliastrum. Dianthus petraeus subsp. simonkaianus was the species with the best multiplication rate (110 shoots/inoculum).