Individual Phenolic Acids Research Articles

The Effect of In Vitro Digestion on Polyphenolic Compounds and Antioxidant Properties of Sorghum (Sorghum bicolor (L.) Moench) and Sorghum-Enriched Pasta.

The phenol content of sorghum is a unique feature among all cereal grains; hence this fact merits the special attention of scientists. It should be remembered that before polyphenols can be used in the body, they are modified within the digestive tract. In order to obtain more accurate data on the level and activity of tested ingredients after ingestion and digestion in the in vivo digestive tract, in vitro simulated digestion may be used. Thus, the aim of this study was to determine the content of polyphenols, flavonoids, and individual phenolic acids, as well as the antiradical properties, of sorghum and sorghum-enriched pasta before and after in vitro simulated gastrointestinal digestion. We observed that the total content of polyphenols decreased after gastric digestion of sorghum, and slightly increased after duodenal digestion. Moreover, the flavonoid content decreased after the first stage of digestion, while antioxidant properties increased after the first stage of digestion and slightly decreased after the second stage. The digestion of polyphenolics in sorghum is completely different to that in pasta-both in varieties with, and without, the addition of sorghum. For pasta, the content of total polyphenols and flavonoids, and free radical scavenging properties, decrease after each stage of digestion.

Characterization of isogenic mutants with single or double deletions of four phenolic acid esterases in Lactiplantibacillus plantarum TMW1.460

In plants, hydroxycinnamic and hydroxybenzoic acids occur mainly as esters. This study aimed to determine the contribution of individual phenolic acid esterases in Lp. plantarum TMW1.460, which encodes for four esterases: TanA, Lp_0796, Est_1092 and a homolog of Lj0536 and Lj1228 that was termed HceP. To determine which of the phenolic acid esterases present in Lp plantarum TMW1.460 are responsible for esterase activity, mutants with deletions in lp_0796, est_1092, tanB, hceP, or hceP and est_1092 were constructed. The phenotype of wild type strain and mutants was determined with esters of hydroxycinnamic acids (chlorogenic acid and ethyl ferulate) and of hydroxybenzoic acids (methyl gallate, tannic acid and epigallocatechin-3-gallate). Lp. plantarum TMW1.460 hydrolysed chlorogenic acid, methyl ferulate and methyl gallate but not tannic acid or epigallocatechin gallate. The phenotype of mutant strains during growth in mMRS differed from the wild type as follows: Lp. plantarum TMW1.460ΔhceP did not hydrolyse esters of hydroxycinnamic acids; Lp. plantarum TMW1.460ΔtanB did not hydrolyse esters of hydroxybenzoic acids; disruption of est_1092 or Lp_0796 did not alter the phenotype. The phenotype of Lp. plantarum TMW1.460ΔΔhceP/est_1092 was identical to Lp. plantarum TMW1.460ΔhceP. The metabolism of phenolic acids during growth of the mutant strains in broccoli puree and wheat sourdough did not differ from metabolism of the wild type strain. In conclusion, esters of hydroxycinnamic and hydroxybenzoic acids each are hydrolysed by dedicated enzymes. The hydroxycinnamic acid esterase HceP is not expressed, or not active during growth of Lp. plantarum TMW1.460 in all food substrates.

Tissue specific changes of phytochemicals, antioxidant, antidiabetic and anti-inflammatory activities of tea [Camellia sinensis (L.)] extracted with different solvents.

Different parts of Camellia sinensis (L.) were extracted with solvents according to polarity, and the extracts' phytochemical profiling and biological activities were examined. The total phenolic (TPC) and total flavonoid (TFC) contents increased with the increasing polarity of the solvent which met its maximum in polar solvents. The increasing antioxidant, anti-inflammatory and antidiabetic activities were recorded with increasing polarity of solvents which showed hydroalcoholic as best solvent. The strong and significant correlation was among the TPC, TFC, DPPH, anti-inflammatory and antidiabetic activities for different parts of tea. HPTLC study of individual phenolic acids, epigallocatechin gallate, gallocatechin and theaflavin met their maximum level of content with polar solvents like hydroalcohol, methanol and water mostly in mainly tea leaves. Our finding suggested that the polar solvents and young leaves of tea were beneficial for obtaining extracts. On the other hand, phenolics were found to be potent antioxidant, anti-inflammatory and antidiabetic agent.

Phenolic Acid Content and Antioxidant Properties of Edible Potato (Solanum tuberosum L.) with Various Tuber Flesh Colours.

The aim of the paper was to evaluate the phenolic acid content and antioxidant properties in potato cultivars with coloured flesh and bright flesh. The study material included eight cultivars of edible potato grown in a temperate climate in Poland. Five cultivars were potato tubers with coloured flesh: "Rote Emma", "Blue Salad", "Vitelotte", "Red Emmalie", and "Blue Congo"; and three were potato tubers with bright flesh: "Bella Rosa", "Lord", and "Tajfun". In all potato samples under study, four phenolic acids were identified: chlorogenic acid, gallic acid, p-coumaric acid, and caffeic acid. The predominant acid was chlorogenic acid, the levels of which ranged from 62.95 mg·100 g-1 FM to 126.77 mg·100 g-1 FM. The total concentration of the identified phenolic acids was diverse and depended on the genotype of the cultivar and the tuber flesh colour, with coloured-fleshed potatoes having higher phenolic acid contents in comparison to bright-fleshed potato cultivars. The average concentration of phenolic acids in the samples was 89.19 mg∙100 g-1 FM, and the average concentrations of the individual phenolic acids identified were as follows: chlorogenic acid (86.19 mg∙100 g-1 FM), gallic acid (1.18 mg∙100 g-1 FM), p-coumaric acid (0.64 mg∙100 g-1 FM), and caffeic acid (1.18 mg∙100 g-1 FM). In addition, three groups of anthocyanins were identified: pelargonidin-3,5-di-O-glucoside, peonidin-3,5-di-O-glucoside, and petunidin-3,5-di-O-glucoside. Anthocyanins were not found in the "Lord" or "Tajfun" varieties characterised by white tuber flesh. The predominant pigment was petunidin-3,5-di-O-glucoside, with an average content of 23.15 mg∙100 g-1 FM, and the highest value was observed in the "Vitelotte" variety (51.27 mg∙100 g-1 FM). The antioxidant activity of the flesh of the potatoes under study was diverse depending on flesh colour. The FRAP (Ferric Reducing Antioxidant Power) assay indicated higher antioxidant activity of coloured-fleshed potato cultivars. The highest concentration was identified in the "Vitelotte" cultivar flesh and was 114% higher than in the "Lord" cultivar. Similar dependencies were found in the case of the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay; however, in this case, the "Vitelotte" cultivar flesh demonstrated nearly 6.4 times higher antioxidant activity than the "Lord" cultivar. Summarizing our own research, we can conclude that potato varieties with coloured flesh are characterised by a higher content of biologically active substances, including phenolic acids, and antioxidant properties compared to potato tubers with bright flesh.

Phytochemical Profiling and Untargeted Metabolite Fingerprinting of the MEDWHEALTH Wheat, Barley and Lentil Wholemeal Flours.

An important research target is improving the health benefits of traditional Mediterranean, durum wheat-based foods using innovative raw materials. In this study, we characterised wholemeal flours obtained from a traditional durum wheat cv. Svevo, two innovative durum wheat varieties (Svevo-High Amylose and Faridur), the naked barley cv. Chifaa and the elite lentil line 6002/ILWL118/1-1, evaluating them for targeted phytochemicals, untargeted metabolomics fingerprints and antioxidant capacity. To this aim, individual phenolic acids, flavonoids, tocochromanols and carotenoids were identified and quantified through HPLC-DAD, and the antioxidant capacities of both the extracts and whole meals were detected by ABTS assays. An untargeted metabolomics fingerprinting of the samples was conducted through NMR spectroscopy. Results showed that the innovative materials improved phytochemical profiles and antioxidant capacity compared to Svevo. In particular, Svevo-HA and Faridur had higher contents of ferulic and sinapic acids, β-tocotrienol and lutein. Moreover, Chifaa is a rich source of phenolic acids, β-tocopherols, lutein and zeaxanthin whereas lentil of flavonoids (i.e., catechin and procyanidin B2). The NMR profiles of Svevo-HA and Faridur showed a significant reduction of sugar content, malate and tryptophan compared to that of Svevo. Finally, substantial differences characterised the lentil profiles, especially for citrate, trigonelline and phenolic resonances of secondary metabolites, such as catechin-like compounds. Overall, these results support the potential of the above innovative materials to renew the health value of traditional Mediterranean durum wheat-based products.

Alginate and β-lactoglobulin matrix as wall materials for encapsulation of polyphenols to improve efficiency and stability

Abstract The present study aimed at developing novel encapsulate materials of calcium-alginate and β-lactoglobulin complex for polyphenols using the jet-flow nozzle vibration method. Encapsulated microbeads were characterized using SEM, FTIR, DSC, and MSI. The encapsulation efficiency of the microbeads varied depending upon the coating material in the range of 74.17–84.87%. Calcium-alginate-β-lactoglobulin microbeads (CABM) exhibited a smooth surface and uniform shape with an average particle size of 1053.73 nm. CABM also showed better thermal and storage stabilities as compared to calcium alginate microbeads. The CABM resulted in excellent target release of polyphenols (84%) in the intestine, which was more than 3-fold the bio-accessibility offered by free polyphenol powder. Further study on individual phenolic acids after simulated in-vitro digestion (SIVD), photo-oxidative and osmotic stress revealed that CABM significantly retained a higher amount of polyphenols and exhibited improved antioxidant capacity after SIVD environment, and may have high industrial application for nutraceutical production.

Phenols, antioxidant and anticancer properties of Tagetes minuta, Euphorbia granulata and Galinsoga parviflora: in vitro and in silico evaluation

This work aimed at assessing the phenolic content, antioxidant and cytotoxicity capacities of methanol extracts obtained from Tagetes minuta, Euphorbia granulata and Galinsoga parviflora medicinal plants. Standard spectrophotometric and chromatographic methods were used for chemical analysis. Established antioxidant and cytotoxicity assays were adopted for biological activity assessment. In silico screening for the individual phenolic acids was performed using molecular docking techniques. E. granulata showed a significantly high level of polyphenols. Highest level of flavonoid and tannin contents were detected in Galinsoga parviflora. Ten phenolic acids were identified and quantified via GC–MS in all extracts, and p-Hydroxybenzoic was the most dominant acid (70 µg/g) in T. minuta while gallic was the predominant acid (73 µg/g) in E. granulata. Extracts showed higher reactive oxygen and nitrogen species scavenging activities and exhibited lower hydrogen peroxide inhibition values. The strongest cytotoxic activity was exhibited by T. minuta extract on A2780 cell line. The cytotoxic activity of G. parviflora extract was highly significant against all cancer cells. Extract of E. granulata showed best activity towards MCF7 and A2780 cell lines and was less active against HT29 cell line. In silico data revealed that caffeic acid had the lowest value of binding energy and high ligand efficiency ratios against the selected target receptors, comparable to the standards. Methanol extracts of the targeted plants showed promising antioxidant and anticancer activities which could be attributed to presence of different phenolic phytochemicals. Further work is required for determining the active compounds and their mode of action.

Prediction of total phenolic acids contained in plant extracts by PLS-ATR-FTIR

Phenols found in plants are becoming increasingly important. Hydroxybenzoic and hydroxycinnamic acids are the predominant phenolic acids. The main objective of this study is to exploit the experiments carried out for the specific quantification of phenolic acids present in plant extracts by PLS-ATR-FTIR to the determination of total phenolic acids (TPA). Individual phenolic acids were measured between 1566 and 563 cm −1 whereas the common band representative of the total phenolic acids was selected between 1737 and 1624 cm −1 . To pass from the quantification of individual-specific phenolic acids to the deduction of the content of total phenolic acids, present in extracts of aromatic plants by PLS-ATR-FTIR, we considered a simple calculation of the concentration of total phenols as being the sum of the concentrations of standard phenols present in the mixtures and the selection of a spectral region common to all the phenolic acids considered. The study developed provides a simple, fast, and precise procedure for the individual simultaneous determination of six phenolic acids (salicylic acid, p-hydroxybenzoic acid, vanillic acid, gallic acid, trans-cinnamic acid, and eugenol) and the estimation of the total phenolic acids present in eighteen extracts of aromatic plants, with the additional advantage of the possibility of examining the plant extracts with a simple plant material extraction by maceration with ethanol which is classified as a green solvent thus providing a green methodology. • Direct estimation of total phenolic acids content in aromatic plants was done by PLS-ATR-FTIR • Quantification of six phenolic acids in aromatic plants without chromatographic separation • Best PLS-ATR-MIR results obtained for the spectral region 1737-1624 cm −1 • Green methodology that only requires ethanol for a simple extraction from plant material

Effect of the Production Parameters and In Vitro Digestion on the Content of Polyphenolic Compounds, Phenolic Acids, and Antiradical Properties of Innovative Snacks Enriched with Wild Garlic (Allium ursinum L.) Leaves.

A new type of corn snack has been created containing additions of wild garlic (Allium ursinum L.). This medicinal and dietary plant has a long tradition of use in folk medicine. However, studies on wild garlic composition and activity are fairly recent and scarce. This research aimed to investigate the influence of the screw speed and A. ursinum amounts on the antiradical properties as well as the content of polyphenolic compounds and individual phenolic acids of innovative snacks enriched with wild garlic leaves. The highest radical scavenging activity and content of polyphenols and phenolic acids were found in the snacks enriched with 4% wild garlic produced using screw speed 120 rpm. The obtained findings demonstrated that snacks enriched with wild garlic are a rich source of polyphenolic compounds. Since the concentration of such compounds is affected by many factors, e.g., plant material, presence of other compounds, and digestion, the second aim of this study was to determine radical scavenging activity, the content of polyphenols, and individual phenolic acids of snacks after in vitro simulated gastrointestinal digestion. Using an in vitro two-stage model, authors noted a significant difference between the concentration of polyphenolic compounds and the polyphenol content of the plant material before digestion.

Differentiation of commercial apple juices based on multivariate analysis of their polyphenolic profiles

The concentration of individual phenolic acids and flavonoids was determined in differently processed commercial apple juices (n = 54) from various product categories, including juices reconstituted from concentrate (FC), both clear and cloudy varieties, as well as not from concentrate (NFC) juices, both fresh and pasteurized products, by means of high−performance liquid chromatography. The studied apple juices were a miscellaneous source of polyphenolics and chlorogenic acid was found to be the dominant polyphenolic compound with a concentration ranging from 29.6 mg L−1 found in fresh juice to 406.8 mg L−1 in pasteurized NFC juice, followed by flavan-3-ols. Pattern recognition techniques including principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were used to explore and classify juices according to polyphenolic profiles. PLS-DA showed satisfactory discrimination between FC and NFC apple juices, the calibration and prediction error rates were 8 % and 12 %, respectively. Based on the variable importance in projection (VIP) and selectivity ratio (SR), individual polyphenolic compounds that contribute significantly to the discrimination of juices were identified. HPLC coupled with pattern recognition methods was found to be a promising tool for grouping commercially available apple juices based on their polyphenolic profile.

Analytical determination of antioxidant capacity of hop-derived compounds in beer using specific rapid assays (ORAC, FRAP) and ESR-spectroscopy

There is a relationship between antioxidant activity and ageing stability of beer. The high-throughput antioxidant capacity assays ORAC and FRAP, which rely on specific reaction mechanisms, are validated as an addition to the established ESR-ST method with a focus on hop-derived antioxidants. Beers were brewed with systematic variations in hop variety, hop product, and the hopping regime (late hopping) to achieve sample beers varying widely in the concentrations of hop-derived antioxidants (α- and iso-α-acids, phenolic compounds). A significant positive correlation between phenolic compounds and the ORAC- and FRAP-values (p < 0.01) was found. The effect of individual resinous substances and free phenolic acids and flavonoids on the antioxidant capacity of beer (ORAC, FRAP, and ESR-ST) was proven in spiking trials. We found a correlation between the occurrence of the o-di-OH-group and the ORAC- and FRAP-values of phenolic compounds. Phenolic compounds did not react as anti- or prooxidants in the radical generation (ESR-ST). Higher concentrations of unisomerized α-acids significantly reduced ESR-signal intensity but had no significant effect on ORAC- or FRAP-values. Beers brewed with late hop addition, which yielded higher concentrations of unisomerized α-acids and phenolic compounds, had higher ORAC, FRAP-values and a reduced ESR-signal intensity. These three methods rely on different reaction principles, and therefore, different groups of hop-derived compounds act as antioxidants in these assays. A combination of the two high-throughput methods (ORAC, FRAP) and ESR-ST is advantageous for the evaluation of the antioxidant capacity of beers varying in hop-derived compounds.

The Yeast Fermentation Effect on Content of Bioactive, Nutritional and Anti-Nutritional Factors in Rapeseed Meal.

The aim of this study was to evaluate the changes in the content of bioactive, nutritional and anti-nutritional factors in rapeseed meal that was fermented with Saccharomyces cerevisiae or Saccharomyces boulardii yeasts at two different periods of time, for improvement of nutritional characteristics in piglets’ feeding. The fermentation has reduced the content of two anti-nutritional factors, intact glucosinolates and 3-butyl isothiocyanate, by 51.60–66.04% and 55.21–63.39%, respectively, by fermentation with either Saccharomyces cerevisiae or Saccharomyces boulardii for 24 h. The fermentation by these yeasts also lowered the content of total polyphenolic compounds by 21.58–23.55% and antioxidant activity (DPPH) by 17.03–21.07%. Furthermore, the content of carbohydrates and organic acids has dramatically decreased between 89.20 and 98.35% and between 31.48 and 77.18%, respectively. However, the content of some individual phenolic acids (gallic, p-coumaric, sinapic) and crude protein content (10–13%) has been increased. Thus, the results showed that fermentation with Saccharomyces cerevisiae or Saccharomyces boulardii has reduced the content of antinutritive factors and increased the protein content of the rapeseed meal, without major adverse effects on its overall nutritive value.

Phenolic compounds and color of labeled resin spurge honey and their correlations with pollen content

Our aim in this study was to outline phenolic and color characteristic that characterize the labeled unifloral resin spurge (Euphorbia resinifera) honey. With respect to phenolic composition, 17 phenolic compounds have been analyzed in the 29 honey samples. The proposed markers (syringic acid, ethyl gallate, m-coumaric acid and naringenin) might help to the enhancement of this honey type and thus, guarantee its commercial value. The color characterization by diffuse reflectance spectrophotometry revealed typical values of light amber honey (lightness ranged from 36 to 70 units, and chroma from 18 to 30 units). On the other hand, many correlations between the color attributes and phenolic acids, total phenolic compounds, caffeic acid, p- and m-coumaric acids and hesperidin have been demonstrated, also, correlation between phenols, color parameters and percentage of pollen of E. resinifera has been found. This study is one of the rare researches which have correlated the CIELAB color parameters with the individual phenolic acids and flavonoid compounds within the same unifloral honey.

Temporal changes of phenolics, flavonoids, carotenoids and mineral constituents in the leaf of a medicinal plant Justicia wynaadensis

Aim: The present study was conducted to investigate the temporal changes in the level of phenolics, flavonoids, carotenoids, and mineral constituents in the leaf extract of medical plant J. wynaadensis (Aati soppu) during monsoon, pre-and post-monsoon season. Methodology: Leaf samples of J. wynaadensis were collected in different seasons (i) first sampling (AS-I) during the onset of monsoon, i.e., first week of July; (ii) second (AS-II) during mid-monsoon (First week of August); and (iii) third sampling (AS-III) during post monsoon (First week of September). The collected samples were analyzed for total carotenoids and chlorophyll, phenolics, flavonoids antioxidant potential, and mineral contents. Individual phenolic acids were identified and quantified using UPLC-H class coupled with TQD-MS/MS. Results: Biochemical constituents significantly varied between the samples of J. wynaadensis collected in different seasons. The samples collected during monsoon season (AS-II) had significantly high amount of phenolics (388.2 mg GAE 100 g-1), flavonoids (287 mg CE 100 g-1), carotenoids (2.40 µg β-CE 100 g-1) when compared with samples collected during pre-and post-monsoon seasons. Among the phenolic acids quantified, Salicylic acid was found to be maximum (2455-4747 μg g-1f.wt.) followed by caffeic acid (350 μg g-1f.wt.). Among the minerals studied potassium was found maximum (240 to 278 mg 100g-1) followed by calcium (263 to 442 mg 100g-1). Leaf samples contained high amount of iron (2.37 to 3.313 mg 100g-1), Except for zinc, most of the micro minerals significantly reduced from onset of monsoon to fag end of monsoon. Interpretation: J. wynaadensis collected at stage AS-II contained significantly high amount of phenolics and flavonoids, which offers numerous health benefits. Increase in content of bioactive phytochemicals such as salicylic acid can be presumed to be responsible for the curative properties of Aati soppu collected during AS-II. Key words: Justicia wynaadensis, Kodagu, Medicinal palnt

Individual Phenolic Acids in Distillery Stillage Inhibit Its Biomethanization

Polyphenols that are abundant in various organic wastes can inhibit anaerobic degradation of these wastes. This study investigated the effect of the concentration of individual phenolic acids (p-OH benzoic, vanillic, ferulic, sinapic, syringic, and p-coumaric acids) and their mixture on the methane potential of distillery stillage. An increase in phenolic acid concentration adversely affected biogas production and composition, as well as the methane-production rate. The inhibition constants for methane production were 0.5–1.0 g/L of individual phenolic acids and 1.5 g/L of the mixture of these acids. At lower concentrations, the phenolic acids were utilized as a carbon source, but the process was impeded when their concentrations exceeded the threshold value, due to their negative effect on microbial growth. When distillery stillage was spiked with vanillic acid, two-phase methane production was observed. Spiking distillery stillage with vanillic, p-coumaric, syringic, or ferulic acids affected anaerobic digestion the most; 2 g/L of these acids completely inhibited methane production. With 4.0 g/L of all individual phenolic acids, no methane production was observed. As the concentration of these phenolic acids increased from 0.5 to 4.0 g/L, the abundance of methanogenic Archaea, in which acetoclastic methanogens predominated, decreased by about 30 times.

Phenolic contents, anticancer, antioxidant, and antimicrobial capacities of MeOH extract from the aerial parts of Trema orientalis plant

Abstract Medicinal plants contain phytochemical components of pharmaceutical importance, and Trema orientalis MeOH extracts are believed to have potential antioxidant and cytotoxic properties. This investigation explores the phenolic, antioxidant, and anticancer property of the methanol extracts of aerial parts of T. orientalis. The total polyphenol content (TPC) and the total flavonoid contents (TFC) were determined following standard methods. In vitro antioxidant property was assessed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. Cytotoxicity experiments were performed against eight cell lines and one fibroblast cell using the methylthiazolyldiphenyl-tetrazolium bromide assay. The antimicrobial activity assay was performed using the agar-diffusion method. Individual phenolic acids identified by GC/MS were examined in silico to estimate their drug likeness based on their structures. TPC and TFC were the highest in the leaf extract, with the strongest radical scavenging activity against ABTS (84.43%) and DPPH (79.60%) radicals. The highest cytotoxicity activity was exhibited by leaf (IC50 = 2.256 ± 0.85 μg/mL) and twig (2.704 ± 1.31 μg/mL) extracts against the HCT116 cell line, followed by bark (3.653 ± 0.05 μg/mL) and leaf (3.725 ± 0.30 μg/mL) extracts against the HT29 cell line. Clonogenicity resulted in a clear decrease of colony formation by HCT116 cells, suggesting a dose-dependent mode. In silico investigation suggested that phenolic acids detected have non-drug-like properties. Extracts showed antimicrobial inactivity.

Diversity of Phytochemical and Antioxidant Characteristics of Black Mulberry (Morus nigra L.) Fruits from Turkey.

Black mulberry (Morus nigra L.) fruits are known due to their delicious, sweet and slightly acid flavor and high anthocyanin content. In the present study, the diversity of phytochemical, sensory, and antioxidant characteristics of the fruits of 20 black mulberry genotypes, from the Artvin region of Turkey, were evaluated. As important phytochemical assessments in fruits, we chromatographically (HPLC/DAD) determined glucose (7.22 to 11.10 g/100 g fresh weight (fw)) and fructose content (6.32 and 9.94 g/100 g fw), as well as predominant organic acid in black mulberry genotypes fruits—malic acid (6.02–11.44 g/100 g fw), followed by citric acid. Titrative determination was used for ascorbic acid, finding contents of 17.41–28.33 mg/100 g fw. There was found a great diversity of sensory (taste, juiciness, and aroma) characteristics, indicating a richness of the fruit germplasm. Antioxidant parameters, such as total phenolic (TP) and anthocyanin (TA) content, were assessed spectrometrically; antioxidant activity (AA) was assessed by DPPH and FRAP assays; individual flavonoids and phenolic acids were determined chromatographically (HPLC/DAD). Antioxidant characteristics of the fruits, defined by TP and TA content, ranged from 1951 to 2733 μg GAE/g fw and 508–712 μg C3GE/g fw, respectively. The most abundant compounds of flavonoids and phenolic acids groups were determined to be rutin (47.10–97.20 mg/100 g fw) and chlorogenic acid (51.3–90.8 mg/100 g fw). AA results, measured by the DPPH method as EC50 value, ranged between 16.10 and 25.45 μg/mL; a FRAP assay revealed values of AA between 9.80 and 13.22 μmol TE/g fw. Significant differences in phytochemical and antioxidant qualities were observed among the analyzed M. nigra genotypes. Regarding the best values of phytochemical and antioxidant characteristics, three genotypes of M. nigra were selected to be recommended for fruit production. The results thus highlight the potential for the exploitation of local black mulberry genotypes through crop selection and breeding program.

Heterophase Synthesis of Humic Substances at Low Substrate Concentrations and Flow-Through Conditions

—Humic substances (HS) are heterogeneous and polydisperse compounds formed in soils, sediments and waters during the decay and transformation of organic residues (the process called humification). The role of extracellular free-radical condensation reactions (secondary synthesis) in the formation of HS is a subject of debate. Here we have studied the formation of HS from a mixture of monomers under the dynamic conditions and at low substrate concentrations in the presence of laccase from the fungus Coprinus comatus F-2940. Laccase was immobilized on kaolinite modified with aluminum hydroxide. We have investigated some properties of the enzyme, reactivity of phenolic acids and amino acids in the presence of laccase. The optimum of 2.6-dimethoxyphenol (2.6-DMP) oxidation by free laccase was at pH 6.0. Upon immobilization, it shifted to the acidic region (pH 4.4), the thermal stability decreased, however the kinetic parameters of 2.6-DMP oxidation remained unchanged. In terms of reactivity (% of substrate conversion by free laccase) the individual phenolic acids formed a series: caffeic (72) > ferulic (53) > gallic = syringic (43) > protocatechuic (5.5) > vanillic = p-hydroxybenzoic (0). In the mixture of phenolic acids, gallic acid was most efficiently oxidized (50%), while the other acids were oxidized in comparable amounts (13–17%). The conversion of phenolic acids increased in the presence of lysine. When a mixture of gallic, protocatechuic, syringic, ferulic acids (0.01 mM each) and lysine (0.02 mM) was passed through a flow-through microcolumn, immobilized laccase effectively oxidized the phenolic acids, the reaction products bound to the mineral phase, staining it dark. According to high performance liquid chromatography, the molecular weights of compounds extracted from the mineral phase did not exceed 900 Da, thus fulvic acid-like substances were formed. Results of the study suggest an important role of free-radical heterophase reactions in the formation of the molecular composition of the liquid phase and organo-mineral complexes.

The Anti-Inflammatory Properties of Chaga Extracts Obtained by Different Extraction Methods against LPS-Induced RAW 264.7.

Chaga, a sclerotia formed by the Inonotus obliquus fungus, has been widely recognized for a number of medicinal properties. Although numerous scientific investigations have been published describing various biological activities of chaga from different geographical locations, little work has focused on chaga harvested in the USA or extraction techniques to maximize anti-inflammatory properties. The aim of this study was to investigate the anti-inflammatory properties of chaga collected in Maine (USA) extracted using traditional aqueous (hot water steeping) methods against lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Chaga extracts obtained from both conventional (ethanol/water) extraction methods and an accelerated solvent extraction method (ASE) at optimized conditions were compared to aqueous extracts (tea) obtained from chaga in the powder form (P) and powder form in tea bags (B) based on their effect on both nitric oxide (NO) production and pro-inflammatory cytokine expression, in particular, the expression of TNF-α, interleukin-6 (IL-6), and interleukin-β (IL-1β). Phenolic acid extracts from chaga and individual phenolic acid standards were also investigated for their effect on the same parameters. Results indicated that various chaga extracts have significant anti-inflammatory activity on LPS-stimulated RAW 264.7 cells. The inhibitory effect was through a decrease in the production of NO and the downregulation of TNF-α, IL-6, and IL-1β in RAW 264.7 macrophages. ASE1 (novel, optimized ethanol/water extraction) and P6 (six-minute steeping of powder in 100 °C water) extracts showed the highest inhibitory activity on NO production and on the expression of the inflammatory cytokines, compared to extracts obtained by conventional extraction methods.

Effects of germination on physio-biochemical metabolism and phenolic acids of soybean seeds

In this study, changes of phenolic acids and antioxidant capacity during germination of soybean seeds were investigated. Results revealed that germination enhanced sprout growth, changed endogenous phytohormones level and caused oxidative damage, but enhanced phenolic acids accumulation. Eight individual phenolic acids in soybean sprouts were identified by HPLC. Gallic acid and protocatechuic acid mainly present in free form, while vanillic acid mainly present in bound form, and p-hydroxybenzoic acid, syringic acid, p-coumaric acid, ferulic acid and sinapic acid were both identified in free and bound phenolic extracts. Both free and bound phenolic acids contents significantly increased during germination. The enzymes activities of phenylalanine ammonia lyase (PAL), cinnamic acid 4-hydroxylase (C4H) and 4-coumarate coenzyme A ligase (4CL) that participated in the biosynthesis of phenolic acids were up-regulated. These results contribute to the further insights into the health-promoting compounds of soybean sprouts.