Phytochemical Compounds and Antioxidant Activity of Two Extracts of Wild and Domesticated Carob Leaves.

<b>Background and Objective:</b> Carob tree (<i>Ceratonia siliqua</i> L.) is a perennial leguminous species and is known as a medicinal importance tree. This species exhibits a myriad of biological effects including antibacterial, antidiarrheal and antidiabetic. To this end, current study evaluates the difference between the phytochemical composition of the leaves of two accessions of "wild" and "domesticated" hermaphroditic carob trees. <b>Materials and Methods:</b> The comparison between two carob accessions "wild" and "domesticated" was done according to methanolic extraction by the Soxhlet and aqueous extraction by maceration. The polyphenols, flavonoids, tannins and their antioxidant activity were measured. The ANOVA test was used for the analysis of results. <b>Results:</b> The total polyphenols in aqueous extract are 6.19±0.25 mg equivalent gallic acid/g dry weight (EGA/g DW) and 4.23±0.2 mg EGA/g DW) in carob fresh leaves for wild and domesticated trees, respectively. The flavonoid content was higher in methanolic extract (3.17±0.64 mg quercetin equivalent/g DW) than in aqueous extract (1.06±0.19 mg EQ/g DW) for wild trees. Wild accession recorded the highest concentration of condensed tannins in the methanolic extract (6.4±0.3 mg catechin equivalents/g DW) while low levels were recorded in aqueous extract (0.51±0.27 mg EC/g DW). <b>Conclusion:</b> Such knowledge is expected to be the key to understanding the biochemical composition of two different leaves of <i>C. siliqua</i> accessions and its various commercial food products.

Global patterns and determinants of the initial concentrations of litter carbon components.

Plant litter is an important carbon (C) and nutrient pool in terrestrial ecosystems. The C components in plant litter are important because they regulate plant litter decomposition rate, but little is known on the global patterns and determinants of their concentrations in freshly fallen plant litter. Here, we quantified the concentrations of leaf litter C components (i.e., carbohydrate, polyphenol, tannin, and condensed tannin) with 864 measurements from 161 independent publications. We found that (1) the mean concentrations of leaf litter carbohydrate, polyphenol, tannin and condensed tannin were 27.7, 6.08, 8.84 and 5.7 %, respectively; (2) the concentrations of leaf litter C components were affected by taxonomic division, mycorrhizal association, life form, and/or leaf shedding strategy; (3) soil property had similar impacts on the concentrations of the four C compounds, while the influence of mean annual temperature and precipitation varied; and (4) elevation had opposing effects on carbohydrate and polyphenol concentrations, but not on that of tannin and condensed tannin, and only carbohydrate concentration was strongly affected by absolute latitude. In general, our results clearly show the global patterns and drivers of the concentrations of litter C compounds, providing new insights into the role of litter decomposition in global C dynamics.

Tracking the changes and bioaccessibility of phenolic compounds of sorghum grains (Sorghum bicolor (L.) Moench) upon germination and seedling growth by UHPLC-QTOF-MS/MS.

In this study, phenolic profile/content was analyzed by high-resolution untargeted metabolomics after short germination (72 h) and seedling growth (144 h), using three sorghum genotypes varying in tannin content (IS 29569, Macia and IS 30400). In vitro antioxidant capacity and phenolic bioaccessibility were determined by microplate-based and INFOGEST methods, respectively. A total of 58 % annotated compounds were found in all genotypes; and phenolic acids and flavonoids represent more than 80 % of sorghum total abundance. PCA analysis showed higher phenolic variability in germination times (72 %) than genotypes (51 %). Germination reduced total ion abundance (-7 %) and free:bound phenolic compounds ratio (2.4-1.1), but antioxidant capacity remained constant. These results indicate the cell matrix-phenolic decomplexation, with the free compounds were quickly consumed after radicle emergence. Germination increased phenolic bioaccessibility (mainly in oral phase) but reduces flavonoids contents in gastric/intestinal digestion steps. This work can stimulate seed germination as a viable option for sorghum-based foods development, with improved nutritional and bioactive properties.

Efficiency enhancement of electrocoagulation, ion-exchange resin and reverse osmosis (RO) membrane filtration by prior organic precipitation for treatment of anaerobically-treated palm oil mill effluent.

Anaerobically-treated palm oil mill effluent (POME) still has unacceptable properties for water recycling and reuse, with an unpleasant appearance due to the brownish color caused by tannins and phenolic compounds. This study proposes an approach for treating anaerobically-treated POME for water recycling by combining organic precipitation, electrocoagulation (EC), and ion-exchange resin, followed by reverse osmosis (RO) membrane filtration in series. The results indicated that the organic precipitation enhanced the efficiency of EC treatment in reducing the concentrations of tannins, color, and chemical oxygen demand (COD) of the anaerobically-treated POME effluent, with reductions of 95.73%, 96.31%, and 93.96% for tannin, color, and COD, respectively. Moreover, organic precipitation affected the effectiveness of Ca2+ and Mg2+ ion removal using ion exchange resin and RO membrane filtration. Without prior organic precipitation, the ion-exchange resin process required a longer contact time, and the RO membrane filtration treatment was hardly effective in removing total dissolved solids (TDS). The combined process gave a water quality that meets the criteria set by the Thailand Ministry of Industry for industrial boiler use (COD 88 mg/L, TDS <0.001 mg/L, water hardness <5 mg-CaCO3/L, and pH 6.9).

Changes in the Physicochemical and Bioactive Properties of Yerba Mate Depending on the Brewing Conditions.

Yerba Mate drink made from dried and crushed leaves and twigs of Paraguayan holly (Ilex paraguariensis A. St.-Hil.), which is a valuable source of bioactive substances, in particular antioxidants. The available literature lacks data on changes in the content and profile of bioactive compounds such as tannins, caffeine, the phenolic acid profile of flavonoids and carotenoids, as well as total polyphenol content and antioxidant activity in Yerba Mate infusions depending on different brewing conditions, and how different brewing conditions affect the physicochemical properties of these infusions. Therefore, this study evaluated the physicochemical properties of dried and Yerba Mate infusions prepared via single and double brewing processes at 70 °C and 100 °C. The organoleptic evaluation, as well as the instrumental color measurement, showed significant changes in the total color difference (ΔE) and the L*a*b* chromatic coordinates of dried Yerba Mate samples and their infusions. Moreover, the research showed higher contents of tannins (mean 1.36 ± 0.14 g/100 g d.m.), caffeine (mean 17.79 ± 3.49 mg/g d.m.), carotenoids (mean 12.90 ± 0.44 µg/g d.m.), phenolic acids (mean 69.97 ± 7.10 mg/g d.m.), flavonoids (mean 5.47 ± 1.78 mg/g d.m.), total polyphenols (mean 55.26 ± 8.51 mg GAE/g d.m.), and antioxidant activity (mean 2031.98 ± 146.47 µM TEAC/g d.m.) in single-brewed Yerba Mate infusions compared to double-brewed (0.77 ± 0.12 g/100 g d.m., 14.28 ± 5.80 mg/g d.m., 12.67 ± 0.62 µg/g d.m., 57.75 ± 8.73 mg/g d.m., 3.64 ± 0.76 mg/g d.m., 33.44 ± 6.48 mg GAE/g d.m. and 1683.09 ± 155.34 µM TEAC/g d.m., respectively). In addition, infusions prepared at a lower temperature (70 °C) were characterized by a higher content of total polyphenols and higher antioxidant activity, in contrast to the tannin and carotenoid contents, the levels of which were higher at 100 °C than at 70 °C. Considering the high amount of bioactive ingredients, in particular antioxidants, and a wide range of health benefits, it is worth including Yerba Mate in the daily diet.

Improving the antinutritional profiles of common beans (Phaseolus vulgaris L.) moderately impacts carotenoid bioaccessibility but not mineral solubility.

Common beans are a common staple food with valuable nutritional qualities, but their high contents in antinutritional factors (ANFs) can decrease the bioavailability of (i) fat-soluble micronutrients including carotenoids and (ii) minerals. Our objective was to select ANF-poor bean lines that would not interfere with carotenoid and mineral bioavailability. To achieve this objective, seeds of commercial and experimental Phaseolus vulgaris L. bean lines were produced for 2 years and the bean's content in ANFs (saponins, phytates, tannins, total polyphenols) was assessed. We then measured carotenoid bioaccessibility and mineral solubility (i.e. the fraction of carotenoid and mineral that transfer into the aqueous phase of the digesta and is therefore absorbable) from prepared beans using in vitro digestion. All beans contained at least 200 mg/100 g of saponins and 2.44 mg/100 g tannins. The low phytic acid (lpa) lines, lpa1 and lpa12 exhibited lower phytate levels (≈ - 80%, p = 0.007 and p = 0.02) than their control BAT-93. However, this decrease had no significant impact on mineral solubility. HP5/1 (lpa + phaseolin and lectin PHA-E free) bean line, induced an improvement in carotenoid bioaccessibility (i.e., + 38%, p = 0.02, and + 32%, p = 0.005, for phytofluene bioaccessibility in 2021 and 2022, respectively). We conclude that decrease in the phytate bean content should thus likely be associated to decreases in other ANFs such as tannins or polyphenols to lead to significant improvement of micronutrient bioaccessibility.

Prussian blue nanocubes with peroxidase-like activity for polyphenol detection in commercial beverages.

The present study describes an efficient method for the determination of polyphenol content in beverages based on a composite material of graphene oxide decorated with Prussian blue nanocubes (rGO/PBNCs). In this method, rGO/PBNCs act as a nanoenzyme with peroxidase-like catalytic activity and produce a colorimetric product in the presence of hydrogen peroxide and tetramethylbenzidine (TMB). To verify the effectiveness of the method, we used two model standards for antioxidants: gallic acid (GA) and tannic acid (TA). The method validation included a comparison of the performance of a natural enzyme and an artificial one (rGO/PBNCs) and two polyphenols in the analysis of commercial beverage samples. After optimization, a pH of 4, ambient temperature (22 °C), a reaction time of 2 minutes and an rGO/PBNCs concentration of 0.01 µg mL-1 were found to be the most favorable conditions. The detection limits obtained were 5.6 µmol L-1 for GA and 1.5 µmol L-1 for TA. Overall, rGO/PBNCs offer advantages over natural enzymes in terms of stability, versatility, scalability and durability, making them attractive candidates for a wide range of catalytic and sensory applications.

Changing the polyphenol composition and enhancing the enzyme activity of sorghum grain by solid-state fermentation with different microbial strains.

BACKGROUND: Solid-state fermentation (SSF) has been widely used in the processing of sorghum grain (SG) because it can produce products with improved sensory characteristics. To clarify the influence of different microbial strains on the SSF of SG, especially on the polyphenols content and composition, Lactiplantibacillus plantarum, Saccharomyces cerevisiae, Rhizopus oryzae, Aspergillus oryzae, and Neurospora sitophila were used separately and together for SSF of SG. Furthermore, the relationship between the dynamic changes in polyphenols and enzyme activity closely related to the metabolism of polyphenols has also been measured and analyzed. Microstructural changes observed after SSF provide a visual representation of the SSF on the SG. RESULTS: After SSF, tannin content (TC) and free phenolic content (FPC) were decreased by 56.36% and 23.48%, respectively. Polyphenol oxidase, ß-glucosidase and cellulase activities were increased 5.25, 3.27, and 45.57 times, respectively. TC and FPC were negatively correlated with cellulase activity. A positive correlation between FPC and xylanase activity after 30 h SSF became negative after 48 h SSF. The SG surface was fragmented and porous, reducing the blocking effect of cortex. CONCLUSION: Cellulase played a crucial role in promoting the degradation of tannin (antinutrient) and phenolic compounds. Xylanase continued to release flavonoids while microbial metabolism consumed them with the extension of SSF time. SSF is an effective way to improve the bioactivity and processing characteristics of SG. © 2024 Society of Chemical Industry.

Antioxidant and UV-blocking activity of PVA/tannin-based bioplastics in food packaging application.

In this study, bioplastics with antioxidant and UV protection properties based on tannin and PVA were created for packaging uses. Using a hot water extraction method at various extraction temperatures (60-100 °C), tannins were removed from the bark of Acacia mangium. Tannins with the best antioxidant activity were extracted at 80 °C. In order to create bioplastic formulations (PVA/Tannins), the extract is then employed. The non-heating bioplastic method's preparation (M3) stage produced the highest levels of antioxidant activity. Therefore, subsequent tests were conducted using the non-heating method (M3). On the opacity, UV protective activity, antioxidant capacity, mechanical strength, thermal stability, and water vapor permeability of the resultant bioplastics, the impact of tannin concentration (0.1-0.5 g) was examined. The findings of the experiments demonstrate that PVA/Tannin bioplastics are less transparent than pure PVA. The PVA/tannin bioplastics that are formed, on the whole, show strong antioxidant and UV protection action. Comparing PVA/Tannin bioplastics to pure PVA also revealed a small improvement in thermal stability and tensile strength. In PVA bioplastics with resistant tannins, moisture content was marginally greater even at low tannin concentrations (0.1 g). Based on the findings, bioplastics made from PVA and the tannin A. mangium have the potential to be used to create packaging that is UV and active antioxidant resistant. It can be applied as the second (inner) layer of the primary packaging to protect food freshness and nutrition due to their antioxidant activity.

Combined effect of harvest time and postharvest dehydration length on the composition of withered grapes for Sforzato di Valtellina DOCG wine production.

BACKGROUND: Sforzato di Valtellina (Sfursat) is a PDO reinforced red wine produced in Valtellina (northern Italy) from partially withered red grapes (Vitis vinifera L.) cv. Nebbiolo. The present study aimed to evaluate the combined influence of different grape ripeness levels and withering length on the chemical composition, mechanical properties, and phenolic profile of Nebbiolo winegrapes from two Valtellina vineyards. During three consecutive vintages (2019, 2020, and 2021), three different technological binomials have been tested: early harvest/long withering (EL), medium-term harvest/medium-term withering (MM), and late harvest/short withering (LS). RESULTS: At the end of the withering process, EL thesis usually presented the highest values of sugars and acidity. Extractable seed polyphenols showed a decreasing trend by leaving the grapes on the plant longer, and this effect increased considerably after withering with respect to fresh samples. EL and MM evidenced the greater concentration of these compounds expressed on grape weight, particularly for tannins. Instead, skin-extracted total phenolics were less influenced by the harvest time, whereas their concentration increased after withering. The harvest time appears to have a higher impact than the withering length on the final extractable anthocyanin content, although the trend was no stable during the vintages or common for the two vineyards evaluated. EL and MM experienced the highest contents of grape skin tannins in most cases, suggesting that a longer withering increases their concentration. CONCLUSION: Harvest time and withering length can be modulated according to the desired oenological objective, promoting the valorization of grape potentialities. The choice to harvest the grapes earlier and enhance the withering length should be preferred to obtain wines with higher acidity and phenolic content, more suitable for long-ageing period. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Phytochemical screening and allelopathic potential of phytoextracts of three invasive grass species.

Undoubtedly, it is important to remain vigilant and manage invasive grasses to prevent their spread and mitigate their negative impact on the environment. However, these aggressive plants can also play a beneficial role in certain contexts. For example, several invasive grasses provide valuable forage for livestock and have disease control potential. Therefore, a research experiment was conducted to explore the pros and cons of this approach, not only for surrounding vegetation but also for human and animal disease control. The study is primarily focused on developing livestock feed, plant-derived herbicides, and an understanding of the phytotoxic effects of invasive species. All plant parts of Cenchrus ciliaris L., Polypogon monspeliansis L., and Dicanthium annulatum (Forssk.) Stapf, were tested for their phyto-chemical screening, proximate, and toxicity analysis which was caused by the methanolic extract of these grass species. Qualitative phytochemical screening tests were performed for proximate composition analysis and toxicity assessment essays. The phytochemical analysis revealed the positive results for alkaloids, flavonoids, coumarins, phenols, saponins, and glycosides, while negative for tannins. Comparison of proximate analysis intimated maximum moisture (10.8%) and crude fat (4.1%) in P. monspeliensis, whereas maximum dry matter (84.1%), crude protein (13.95%), crude fiber (11%), and ash (7.2%) in D. annulatum. Five (10, 100, 500, 100, 10,000 ppm) and three (10, 1000, 10,000 ppm) different concentrations of methanolic extract prepared from C. ciliaris, P. monspeliansis, and D. annulatum were used respectively for root inhibition and seed germination essay. Furthermore, three different concentrations (10, 30, 50 mg) of plant fine powder were used for sandwich method test. There was a significant decline in the growth rate of experimental model radish seeds (P > 0.005), and results from sandwich method tests showed suppressed growth of root hairs, inhibiting the anchoring of the radish seed. In comparison, results manifest that; P. monspeliansis indicated an upsurge of inhibition (66.58% at 10,000 ppm), D. annulatum revealed soar germination (75.86% in controlled conditions), and C. ciliaris exhibited dramatic shoot up of inhibition because of sandwich method test (14.02% at 50 mg). In conclusion, although grasses are toxic, it is important to consider the beneficiary account.

Variation in Phenolic Compounds, Antioxidant and Antibacterial Activities of Extracts from Different Plant Organs of Meadowsweet (Filipendula ulmaria (L.) Maxim.).

Meadowsweet (Filipendula ulmaria (L.) Maxim.) has been widely used in the treatment of various diseases. The pharmacological properties of meadowsweet are derived from the presence of phenolic compounds of a diverse structure in sufficiently large quantities. The purpose of this study was to examine the vertical distribution of individual groups of phenolic compounds (total phenolics, flavonoids, hydroxycinnamic acids, catechins, proanthocyanidins, and tannins) and individual phenolic compounds in meadowsweet and to determine the antioxidant and antibacterial activity of extracts from various meadowsweet organs. It was found that the leaves, flowers, fruits, and roots of meadowsweet are characterized by a high total phenolics content (up to 65 mg g-1). A high content of flavonoids was determined in the upper leaves and flowers (117-167 mg g-1), with high contents of hydroxycinnamic acids in the upper leaves, flowers, and fruits (6.4-7.8 mg g-1); high contents of catechins and proanthocyanidins in the roots (45.1 and 3.4 mg g-1, respectively); and high tannin content in the fruits (38.3 mg g-1). Analysis of extracts by high-performance liquid chromatography (HPLC) showed that the qualitative and quantitative composition of individual phenolic compounds in various parts of the meadowsweet varied greatly. Among the flavonoids identified in meadowsweet, quercetin derivatives dominate, namely quercetin 3-O-rutinoside, quercetin 3-ß-d-glucoside, and quercetin 4'-O-glucoside. Quercetin 4'-O-glucoside (spiraeoside) was found only in the flowers and fruits. Catechin was identified in the leaves and roots of meadowsweet. The distribution of phenolic acids across the plant was also uneven. In the upper leaves, a higher content of chlorogenic acid was determined, and in the lower leaves, a higher content of ellagic acid determined. In flowers and fruits, a higher contents of gallic, caftaric, ellagic, and salicylic acids were noted. Ellagic and salicylic acids were also dominant among phenolic acids in the roots. Based on the results of the analysis of antioxidant activity in terms of the ability to utilize the radicals of 2,2-diphenyl-1-picrylhydrazine (DPPH) and 2,2'-azino-bis(3-ethylbenzthiazolino-6-sulfonic acid) (ABTS) and in terms of iron-reducing ability (FRAP), the upper leaves, flowers, and fruits of meadowsweet can be considered plant raw materials suitable to obtain extracts with high antioxidant activity. Extracts of plant fruits and flowers also showed high antibacterial activity against the bacteria Bacillus subtilis and Pseudomonas aeruginosa.

Changes in Physicochemical and Bioactive Properties of Quince (Cydonia oblonga Mill.) and Its Products.

Quince (Cydonia oblonga Miller) is a plant that is commonly cultivated around the world, known for centuries for its valuable nutritional and healing properties. Although quince fruit are extremely aromatic, due to their high hardness and sour, astringent, and bitter taste, they are not suitable for direct consumption in an unprocessed form. However, they are an important raw material in fruit processing, e.g., in the production of jams, jellies, and juices. Quince fruits fall under the category of temperate fruits, so their shelf life can be predicted. Considering that technological processing affects not only the organoleptic properties and shelf life but also the functional properties of fruits, the aim of this research was to determine the impact of various types of technological treatments on the physicochemical and bioactive properties of quince fruit. In fresh, boiled, and fried fruits and in freshly squeezed quince fruit juice, basic parameters, such as the content of dry matter, moisture, soluble solids (°Brix), pH, total acidity, water activity, and color parameters (L*a*b*) were determined. The content of key bioactive ingredients, i.e., tannins, carotenoids, flavonoids, phenolic acids, and total polyphenols, was also determined, as well as the antioxidant activity of raw and technologically processed (cooked, fried, and squeezed) quince fruits. The conducted research showed that fresh quince fruit and processed quince products can be a very good source of bioactive ingredients in the diet, such as tannins (3.64 ± 0.06 mg/100 g in fresh fruit; from 2.22 ± 0.02 mg/100 g to 5.59 ± 0.15 g/100 g in products), carotenoids (44.98 ± 0.18 mg/100 g in fresh fruit; from 141.88 ± 0.62 mg/100 g to 166.12 ± 0.62 mg/100 g in products), and polyphenolic compounds (246.98 ± 6.76 mg GAE/100 g in fresh fruit; from 364.53 ± 3.76 mg/100 g to 674.21 ± 4.49 mg/100 g in products). Quince fruit and quince products are also characterized by high antioxidant properties (452.41 ± 6.50 µM TEAC/100 g in fresh fruit; 520.78 ± 8.56 µM TEAC/100 g to 916.16 ± 6.55 µM TEAC/100 g in products). The choice of appropriate technological processing for the quince fruit may allow producers to obtain high-quality fruit preserves and act a starting point for the development of functional products with the addition of quince fruit in its various forms, with high health-promoting values and a wide range of applications in both the food and pharmaceutical industries.

Straightforward smartphone assay for quantifying tannic acid in beverages based on colour change of Eu3+/polyethyleneimine complex.

Tannic acid (TA)-a natural product-is a polyphenol derivative that occurs in certain kinds of beverages. A large amount of TA could give rise to an unpleasant flavour and could negatively affect the human body by causing stomach irritation, abdominal pain, nausea, vomiting, and even death. Thus, the need exists for a simple TA detection procedure that meets specific criteria such as on-site analysis, portability, and affordability. Herein, we present a new TA assay, which is based on the fluorescent quenching effect of an efficient fluorophore, and which comprises a smartphone-integrated homemade reader system. The fluorescent polyethyleneimine-derivatised polymer (FP), a strong emitter at 510 nm, was synthesised with the aid of a facile sonication method. In the presence of Eu3+ ions, TA quenches the fluorescence of the FP via electrostatic interaction. A smartphone was used to capture an image of the FP undergoing fluorescence for conversion to RGB values. The blue channel was chosen for further analysis because it offered the highest R2-value compared to the red and green channels. We verified these results using a commercial spectrofluorometer and calculated the limit of detection of this assay as 87 nM and 20 nM for the homemade reader and spectrofluorometer, respectively. The detection range for TA with the proposed assay is 0.16-66.66 µM. The application of the proposed method to real beverage samples for TA detection demonstrates its analytical applicability.

Phytochemical profile, in vitro activities, and toxicity of optimized Eugenia uniflora extracts / Perfil fitoquímico, actividades in vitro y toxicidad de extractos optimizados de Eugenia uniflora

In this study, we investigated the influence of mixture design on the chemical profile of Eugenia unifloraleaves, evaluating the antioxidant and antimicrobial activities, the toxic and hemolytic potential, with the focus on the improvement of the polyphenol's extraction for incorporation of the extract in semi-solid forms with antifungal action. The chemical analysis was evaluated by UV-Vis and HPLC. The antimicrobial, antioxidant, and hemolytic activities were monitored. The flavonoid content ranged from 2.63-7.98 %w/w and tannins from 5.42-18.29 %w/w. The extract consisted of gallic acid (0.09-1.29%; w/w), ellagic acid (0.09-0.37%; w/w), and myricitrin (0.18-1.20%; w/w). The most successful solvent system with the highest level of active extract was water: ethanol: propylene glycol. The extracts showed fungicidal properties (3.9 µg/mL), high antioxidant activity (IC50: 9.50 µg/mL), and low toxicity. These solvent mixtures can improve the in vitro bioactivities when compared to pure solvents and this result demonstrates the importance of mixture designs as useful tools for creating high-quality herbal products and elucidate the potential of E. uniflora glycolic extracts as active herbal pharmaceutical ingredients in topical delivery systems.

En este estudio investigamos la influencia del diseño de mezclas en el perfil químico de hojas de Eugenia uniflora, evaluando las actividades antioxidantes y antimicrobianas, el potencial tóxico y hemolítico, con el foco en la mejora de la extracción de polifenoles para la incorporación del extracto en formas semi-sólidas con acción antifúngica. El análisis químico se evaluó mediante UV-Vis y HPLC. Se monitorizaron las actividades antimicrobianas, antioxidantes y hemolíticas. El contenido de flavonoides osciló entre 2,63 y 7,98% p/p and taninos de 5,42-18,29% p/p. El extracto consistió en ácido gálico (0.09-1.29%; p/p), ácido elágico (0.09-0.37%; p/p) y miricitrina (0.18-1.20%; p/p). El sistema de disolventes más exitoso con el nivel más alto de extracto activo fue agua: etanol: propilenglicol. Los extractos mostraron propiedades fungicidas (3.9 µg/mL), alta actividad antioxidante (IC50: 9.50 µg/mL) y baja toxicidad. Estas mezclas de disolventes pueden mejorar las bioactividades in vitro en comparación con los disolventes puros y este resultado demuestra la importancia de los diseños de mezclas como herramientas útiles para crear productos a base de hierbas de alta calidad y dilucidar el potencial de los extractos glicólicos de E. uniflora como ingredientes farmacéuticos a base de hierbas en sistemas de entrega activos.

Diffusion of phenolic compounds during a model maceration in winemaking: role of flesh and seeds.

BACKGROUND: During red winemaking, diffusion of phenolic compounds from the grape berry cells into the liquid phase occurs simultaneously with the adsorption of the same compounds onto the pulp. In previous studies, we quantified the proportions of polyphenols diffusing from the skins and then assessed the amounts that can be fixed by the pulp. In this work, we added the impact of seeds, also present during vinification, by carrying out macerations in a model medium with the following berry compartments: skins, seeds, skins + seeds, skins + seeds + pulp. RESULTS: Interestingly, the seeds alone released a rather high amount of polyphenols. As soon as they were in the presence of cell walls of skin/flesh, and/or anthocyanins, the concentration of seed tannins in the solution dropped dramatically, due to a combined effect of adsorption and/or precipitation and/or chemical reactions. The pulp certainly adsorbed tannins, but they also tended to shift the extraction equilibria, and it seems that more tannins could be extracted from skins and seeds when pulp was present. Polyphenol amounts extracted in model systems with skins + seeds + pulp were close to what was extracted in microvinification. CONCLUSION: These model experiments reflect relatively well extraction during microvinification experiments and highlight the respective impact of the grape berry's different compartments in the wine's final phenolic composition as well as some of the mechanisms involved. © 2022 Society of Chemical Industry.

Water-soluble phenolic compounds and their putative antioxidant activities in the seed coats from different lentil (Lens culinaris) genotypes.

The seed coat is a major byproduct of lentil processing with potential as a sustainable source of antioxidant polyphenols. Profiles of water-soluble phenolic compounds and antioxidant activities of seven genotypes of lentil which includes both normal-tannin and low-tannin seed coats were investigated. Antioxidant activities were assessed using four antioxidant assays, and phenolic compounds were quantified using liquid chromatography mass spectrometry (LC-MS). Total phenolic content (TPC) varied significantly among genotypes and ranged between 1519 ± 140 and 6502 ± 154 µg/g. Thirty phenolic compounds were identified with kaempferol tetraglycoside, catechin-3-glucoside and procyanidins being the dominant compounds in normal-tannin seed coats. Kaempferol tetraglycoside predominated (80-90%) in low-tannin seed coats. Antioxidant activities strongly correlated with TPC (r > 0.93) with a 6-9 times higher activity in normal-tannin than that of low-tannin lentils. Without flavan-3-ols and procyanidins, low-tannin seed coat may not exert strong antioxidant potential, whereas normal-tannin seed coat contains water-extractable natural phenolic compounds with promising antioxidant potential.

Focus on the relationships between the cell wall composition in the extraction of anthocyanins and tannins from grape berries.

Concentrations of anthocyanins and tannins after extraction from berries in wines and from skin macerations in model solutions have been studied for two grape varieties, two maturation levels and two vintages berries. Characterization of the cell wall polysaccharides has also been performed, the classical method based on the analysis of the neutral sugars after depolymerization being completed by a comprehensive microarray polymer profiling (CoMPP). Extraction was lower in model solutions than in wines, with the same ranking: non acylated anthocyanins> tannins > p-coumaroylated anthocyanins. The polysaccharidic composition suggested a role of homogalacturonans, rhamnogalacturonans and extensins in the extraction process. A global explanation of the interactions between anthocyanins, tannins and polysaccharides is proposed.

Halimeda gracilis (Kadarpassi chooranam) Phytochemical analysis and biological significance - a novel Siddha drug.

OBJECTIVES: To evaluate biological activity and the phytochemical analysis of kadarpassi chooranam. Seaweeds are the marine macro algae, species belonging to Protista kingdom that has no true system, internal vascular systems, seeds and flowers. It has a lot of biological activity and has been proven to have a lot of medicinal benefits. Since time immemorial, their usage in traditional medicine has been recognized. METHODS: Halimeda gracilis has been standardized as per siddha pharmacopoeia standard protocol guidelines and prepared kadarpassi Chooranam curtained for Phytochemical analysis (qualitative and quantitative) and carried out various pharmacological activity. RESULTS: The antioxidant, anti-inflammatory, and anti-cancer actions of kadarpassi Chooranam have been associated to alkaloids, phenols, flavonoids, cardiac glycosides, saponins, tannins, and diterpenes. CONCLUSIONS: The Siddha medicine, kadarpassi chooranam has various phytochemical bioactive compounds, and because of its pharmacological activity can be a potential drug candidate for human use.

Developing novel oenological tannins from 44 plants sources by assessing astringency and color in model wine.

BACKGROUND: Oenological tannins are commercial natural products extracted from different botanical sources, which were widely reported as prominent contributors to wine quality. Research on wine quality affected by tannins extracts promoted the development of new oenological products with low cost and high accessibility. In the present study, the structure and concentration of tannin in polyphenol extracts, as well as their correlation with astringency and the color of model wine, was investigated by UV spectrophotometer, HPLC, fluorescence quenching, sodium dodecylsulfate-polyacrylamide gel electrophoresis, colorimeter and sensory evaluation. RESULTS: Resource extracts from 16 of 44 plants were screened as wine oenological tannins, according to the total polyphenol and total flavanol, as well as the intensity of astringency and bitterness. Polyphenols extracted from grape seeds and green tea were more effective in increasing the wine astringency compared to other plant tannins. CONCLUSION: Total flavanol content and tannin activity showed a strong correlation with wine astringency. Condensed tannins with mean degree of polymerization also exhibited strong color stability, and the concentrations of (-)-epigallocatechin were associated with the a* value, a negative qualitative factor for wine color. The present study provides new clues regarding the development of low-cost and highly accessible sources of polyphenol extracts and lays a theoretical foundation for the development of the oenological product. © 2022 Society of Chemical Industry.