Potential interventions and interactions of bioactive polyphenols and functional polysaccharides to alleviate inflammatory bowel disease - A review.

Inflammatory bowel disease is a multifaceted condition that is influenced by nutritional, microbial, environmental, genetic, psychological, and immunological factors. Polyphenols and polysaccharides have gained recognition for their therapeutic potential. This review emphasizes the biological effects of polyphenols and polysaccharides, and explores their antioxidant, anti-inflammatory, and microbiome-modulating properties in the management of inflammatory bowel disease (IBD). However, polyphenols encounter challenges, such as low stability and low bioavailability in the colon during IBD treatment. Hence, polysaccharide-based encapsulation is a promising solution to achieve targeted delivery, improved bioavailability, reduced toxicity, and enhanced stability. This review also discusses the significance of covalent and non-covalent interactions, and simple and complex encapsulation between polyphenols and polysaccharides. The administration of these compounds in appropriate quantities has proven beneficial in preventing the development of Crohn's disease and ulcerative colitis, ultimately leading to the management of IBD. The use of polyphenols and polysaccharides has been found to reduce histological scores and colon injury associated with IBD, increase the abundance of beneficial microbes, inhibit the development of colitis-associated cancer, promote the production of microbial end-products, such as short-chain fatty acids (SCFAs), and improve anti-inflammatory properties. Despite the combined effects of polyphenols and polysaccharides observed in both in vitro and in vivo studies, further human clinical trials are needed to comprehend their effectiveness on inflammatory bowel disease.

Polyphenol Treatment of Peripheral Blood Mononuclear Cells from Individuals of Different Ages.

Human peripheral blood mononuclear cells (PBMCs) have been largely utilized to assess the cytotoxic, immunomodulatory, and anti-inflammatory properties of both synthetic and natural compounds. Within the latter category, polyphenols from dietary sources have been extensively analyzed. PBMCs represent a feasible in vitro model to study polyphenol hallmarks and activity according to quantitative and qualitative differences in immune responses in individuals of different age. In this chapter, we propose a method for PBMC treatment with polyphenols and analysis designed on age-dependent qualitative and quantitative variability in immune cell performance.

Different polysaccharide-enhanced probiotic and polyphenol dual-functional factor co-encapsulated microcapsules demonstrate acute colitis alleviation efficacy and food fortification.

Probiotics and polyphenols have multiple bioactivities, and developing co-encapsulated microcapsules (CM) is a novel strategy to enhance their nutritional diversity. However, the development of CMs is challenged by complicated processing, single types, and unclear in vivo effects and applications. In this study, the co-microencapsulations of polyphenol and probiotic were constructed using pectin, alginate (WGCA@LK), and Fu brick tea polysaccharides (WGCF@LK), respectively, with chitosan-whey isolate proteins by layer-by-layer coacervation reaction, and their protective effects, in vivo effectiveness, and application potential were evaluated. WGCA@LK improved the encapsulation rate of polyphenols (42.41 %), and remained high viability of probiotics after passing through gastric acidic environment (8.79 ± 0.04 log CFU/g) and storage for 4 weeks (4.59 ± 0.06 log CFU/g). WGCF@LK exhibited the highest total antioxidant activity (19.40 ± 0.25 µmol/mL) and its prebiotic activity removed the restriction on probiotic growth. WGCA@LK showed strong in vitro colonic adhesion, but WGCF@LK promoted in vivo retention of probiotics at 48 h. WGCF@LK showed excellent anti-inflammatory effects and alleviated symptoms of acute colitis in mice. These findings provide unique insights into the fortification of probiotic-polyphenol CMs by different polysaccharides and the development of novel health foods with rich functional hierarchies and superior therapeutic effects.

Controlled preparation of tannic acid-derived carbonized dots and their use to inhibit amyloid aggregation and promote aggregate disaggregation.

Tannic acid (TA)-derived carbon dots (TACDs) were synthesized for the first time via a solvothermal method using TA as one of the raw materials, which may effectively inhibit amyloid fibril aggregation and disaggregate mature fibril. The fluorescent property of TACDs were modulated by adjusting the ratio of TA to o-phenylenediamine (oPD), and TACDs fabricated with the precursor ratio as 1:1 showed the best fluorescent property. Circular dichroism spectra (CD) showed that the structure of ß-sheet decreased as the concentration of TACDs increased. The inhibition efficiency, as confirmed by thioflavin T (ThT) and transmission electron microscopy (TEM), is extraordinary at 98.16%, whereas disaggregation efficiency is noteworthy at 97.97%, and the disaggregated lysozyme fibrils did not reaggregate after 7 days. More critically, TACDs can also alleviate the cellular toxicity caused by Aß fibrils and improve cell viability. This work offers a new perspective on the design of scavengers for amyloid plaques.

Impact of traditional and innovative cooking techniques on Italian black rice (Oryza sativa L., Artemide cv) composition.

Due to its high polyphenol content, black rice plays a significant role in good nutrition; however, these antioxidant compounds are affected by heat treatments required for the rice consumption. The aim of this work was to investigate how cooking affects the composition of Artemide black rice, comparing innovative methods, such as sous vide, with traditional domestic techniques (risotto and pilaf). Proteins and ashes were not affected by cooking, except for pilaf rice, where a 42 % ashes decrease was observed; fiber content increased after all cooking methods, reaching a 29 % increase in the risotto. Antioxidant activity, total polyphenols, anthocyanins and proanthocyanidins were reduced on average of 40 %, 34 %, 43 % and 39 %, respectively. Individual anthocyanins decreased, while phenolic acids and other flavonoids presented different behaviours, also depending if considered in their free or bound form. Cyanidin-3-O-glucoside was reduced up to 56 % in the sous vide cooked rice at 99 °C, and only by 45 % and 37 % in the risotto and sous vide cooked rice at 89 °C, respectively. Traditional risotto preparation and the innovative sous vide cooking at 89 °C also maintained the highest antioxidant polyphenols content, saving 63 % of the antioxidant activity in respect to the raw black rice. Concluding, these last techniques can be suggested for a better preservation of bioactive compounds.

The influence mechanism of pH and polyphenol structures on the formation, structure, and digestibility of pea starch-polyphenol complexes via high-pressure homogenization.

The formation of starch-polyphenol complexes through high-pressure homogenization (HPH) is a promising method to reduce starch digestibility and control postprandial glycemic responses. This study investigated the combined effect of pH (5, 7, 9) and polyphenol structures (gallic acid, ferulic acid, quercetin, and tannic acid) on the formation, muti-scale structure, physicochemical properties, and digestibility of pea starch (PS)-polyphenol complexes prepared by HPH. Results revealed that reducing pH from 9 to 5 significantly strengthened the non-covalent binding between polyphenols and PS, achieving a maximum complex index of 13.89 %. This led to the formation of complexes with higher crystallinity and denser structures, promoting a robust network post-gelatinization with superior viscoelastic and thermal properties. These complexes showed increased resistance to enzymatic digestion, with the content of resistant starch increasing from 28.66 % to 42.00 %, rapidly digestible starch decreasing from 42.82 % to 21.88 %, and slowly digestible starch reducing from 71.34 % to 58.00 %. Gallic acid formed the strongest hydrogen bonds with PS, especially at pH 5, leading to the highest enzymatic resistance in PS-gallic acid complexes, with the content of resistant starch of 42.00 %, rapidly digestible starch of 23.35 % and slowly digestible starch of 58.00 %, and starch digestion rates at two digestive stages of 1.82 × 10-2 min-1 and 0.34 × 10-2 min-1. These insights advance our understanding of starch-polyphenol interactions and support the development of functional food products to improve metabolic health by mitigating rapid glucose release.

Gastrointestinal digestion of yerba mate, rosemary and green tea extracts and their subsequent colonic fermentation by human, pig or rat inocula.

Polyphenolic compounds are common constituents of human and animal diets and undergo extensive metabolism by the gut microbiota before entering circulation. In order to compare the transformations of polyphenols from yerba mate, rosemary, and green tea extracts in the gastrointestinal tract, simulated gastrointestinal digestion coupled with colonic fermentation were used. For enhancing the comparative character of the investigation, colonic fermentation was performed with human, pig and rat intestinal microbiota. Chemical analysis was performed using a HPLC system coupled to a diode-array detector and mass spectrometer. Gastrointestinal digestion diminished the total amount of phenolics in the rosemary and green tea extracts by 27.5 and 59.2 %, respectively. These reductions occurred mainly at the expense of the major constituents of these extracts, namely rosmarinic acid (-45.7 %) and epigalocatechin gallate (-60.6 %). The yerba mate extract was practically not affected in terms of total phenolics, but several conversions and isomerizations occurred (e.g., 30 % of trans-3-O-caffeoylquinic acid was converted into the cis form). The polyphenolics of the yerba mate extract were also the least decomposed by the microbiota of all three species, especially in the case of the human one (-10.8 %). In contrast, the human microbiota transformed the polyphenolics of the rosemary and green extracts by 95.9 and 88.2 %, respectively. The yerba mate-extract had its contents in cis 3-O-caffeoylquinic acid diminished by 78 % by the human microbiota relative to the gastrointestinal digestion, but the content of 5-O-caffeoylquinic acid (also a chlorogenic acid), was increased by 22.2 %. The latter phenomenon did not occur with the rat and pig microbiota. The pronounced interspecies differences indicate the need for considerable caution when translating the results of experiments on the effects of polyphenolics performed in rats, or even pigs, to humans.

Fabrication and characterization of tea seed starch-tea polyphenol complexes.

This study investigates the complexation between tea seed starch (TSS) and tea polyphenols (TPs) at varying concentrations (2.5, 5.0, 7.5, and 10.0 %). The objectives can expand the knowledge of TSS, which is a novel starch, and to examine how TPs influence the structure and physicochemical properties of the complexes. Results indicate that TPs interact with TSS through hydrogen bonding, altering granule morphology and disrupting ordered structure of starch. Depending on the concentration, TPs induce either V-type or non-V-type crystal structures within TSS, which had bearing on iodine binding capacity, swelling, pasting, gelatinization, retrogradation, rheology, and gel structure. In vitro digestibility analysis reveals that TSS-TPs complexes tend to reduce readily digestible starch while increasing resistant starch fractions with higher TP concentrations. Thus, TSS-TPs complexes physicochemical and digestibility properties can be modulated, providing a wide range of potential applications in the food industry.

Molecular Mechanisms of Polyphenols in Management of Skin Aging.

The natural process of skin aging is influenced by a variety of factors, including oxidative stress, inflammation, collagen degradation, and UV radiation exposure. The potential of polyphenols in controlling skin aging has been the subject of much investigation throughout the years. Due to their complex molecular pathways, polyphenols, a broad class of bioactive substances present in large quantities in plants, have emerged as attractive candidates for skin anti-aging therapies. This review aims to provide a comprehensive overview of the molecular mechanisms through which polyphenols exert their anti-aging effects on the skin. Various chemical mechanisms contribute to reducing skin aging signs and maintaining a vibrant appearance. These mechanisms include UV protection, moisturization, hydration, stimulation of collagen synthesis, antioxidant activity, and anti-inflammatory actions. These mechanisms work together to reduce signs of aging and keep the skin looking youthful. Polyphenols, with their antioxidant properties, are particularly noteworthy. They can neutralize free radicals, lessening oxidative stress that might otherwise cause collagen breakdown and DNA damage. The anti-inflammatory effects of polyphenols are explored, focusing on their ability to suppress pro-inflammatory cytokines and enzymes, thereby alleviating inflammation and its detrimental effects on the skin. Understanding these mechanisms can guide future research and development, leading to the development of innovative polyphenol-based strategies for maintaining healthy skin.

Blackthorn fruit peel polyphenol extracts and photodynamic effect under blue light against Listeria monocytogenes.

Photodynamic inactivation is an emerging antimicrobial treatment that can be enhanced by employing exogenous photosensitizers to eradicate foodborne pathogens. This study investigated a novel combinatory strategy to eradicate Listeria monocytogenes using blackthorn fruit peel (BFP) and blue light (BL). Extracts of BFP were characterized in terms of polyphenolic content, individual constituents, and antioxidant and antimicrobial activity. The concentration of phenolic compounds and antioxidant activity were both found to be determinants of antimicrobial activity. It was further speculated that flavonols, predominantly quercetin and rutin, were responsible for the activity of BFP against L. monocytogenes. A combination of BFP and BL resulted in a rapid inactivation of the pathogen by up to 4 log CFU/mL at 58.5 J/cm2, corresponding to 15 min BL illumination. Flow cytometry analysis revealed that the bacterial cells lost activity and suffered extensive membrane damage, exceeding 90% of the population. After photosensitizing L. monocytogenes with the BFP constituents quercetin and rutin, a 1.3-log reduction was observed. When applied together, these compounds could inflict the same damaging effect on cells as they did individually when effects were added. Therefore, the results indicate that BFP represents a natural source of (pro-)photosensitizers, which act additively to create inactivation effects. This study may help identify more effective plant-based photosensitizers to control L. monocytogenes in food-related applications.

Biological activities of derived pigments and polyphenols from the newly recorded alga Phyllymenia gibbesii.

The newly recorded Phyllymenia gibesii in the Mediterranean Sea at Alexandria coast of Egypt is regarded as a significant source of bioactive substances and is applied as an antioxidant, anti-inflammatory, and antimicrobial agent. According to the HPLC chromatograms, the acetone extract of P. gibesii comprised ten photosynthetic pigments (chlorophyll-a, chlorophyll-d, α-carotene, ß-carotene, phycocyanin, allophycocyanin, antheraxanthin, ß-cryptoxanthin, lutein, and violaxanthin). Total carotenoids were the dominant class in the pigments' profile, achieving a concentration of 257 g/g dry weight. The P. gibbesii extract had a total content of phenols (146.67 mg/g) and a total content of flavonoids (104.40 mg/g). The capacity of all the investigated biological activities augmented with the concentration of the algal extract. The maximal DPPH scavenging capacity was 81.44%, with an inhibitory concentration (IC50) of 9.88 µg/mL. Additionally, the highest ABTS scavenging capacity was 89.62%, recording an IC50 of 21.77 µg/mL. The hemolytic activity of P. gibbesii attained a maximum capacity of 49.88% with an IC50 of 100.25 µg/mL. Data also showed the maximum anti-inflammatory effectiveness at 81.25%, with an IC50 of 99.75 µg/mL. Furthermore, the extract exhibited antimicrobial capacity against all reference strains, particularly at high concentrations (0.1 mg/mL), with the greatest effect on C. albicans and E. coli.

Advancements in Plant-Based Therapeutics for Hepatic Fibrosis: Molecular Mechanisms and Nanoparticulate Drug Delivery Systems.

Chronic liver injuries often lead to hepatic fibrosis, a condition characterized by excessive extracellular matrix accumulation and abnormal connective tissue hyperplasia. Without effective treatment, hepatic fibrosis can progress to cirrhosis or hepatocellular carcinoma. Current treatments, including liver transplantation, are limited by donor shortages and high costs. As such, there is an urgent need for effective therapeutic strategies. This review focuses on the potential of plant-based therapeutics, particularly polyphenols, phenolic acids, and flavonoids, in treating hepatic fibrosis. These compounds have demonstrated anti-fibrotic activities through various signaling pathways, including TGF-ß/Smad, AMPK/mTOR, Wnt/ß-catenin, NF-κB, PI3K/AKT/mTOR, and hedgehog pathways. Additionally, this review highlights the advancements in nanoparticulate drug delivery systems that enhance the pharmacokinetics, bioavailability, and therapeutic efficacy of these bioactive compounds. Methodologically, this review synthesizes findings from recent studies, providing a comprehensive analysis of the mechanisms and benefits of these plant-based treatments. The integration of novel drug delivery systems with plant-based therapeutics holds significant promise for developing effective treatments for hepatic fibrosis.

Highly Specific Polyphenolic Colloids as Alternatives to Antimicrobials in Livestock Production.

The dispersion of antibiotics in livestock farming represents a health concern worldwide, contributing to the spread of antimicrobial-resistant bacteria through animals, the environment, and humans. Phenolic compounds could be alternatives to antibiotics, once drawbacks such as their low water solubility, bioavailability, and reduced stability are overcome. Although nano- or micro-sized formulations could counter these shortcomings, they do not represent cost-effective options. In this study, three phenolic compounds, obtained from wood-processing manufacturers, were characterized, revealing suitable features such as their antioxidant activity, size, and chemical and colloidal stability for in-field applications. The minimum inhibitory concentration (MIC) of these colloidal suspensions was measured against six bacterial strains isolated from livestock. These particles showed different inhibition behaviors: Colloidal chestnut was effective against one of the most threatening antibiotic-resistant pathogens, i.e., S. aureus, but ineffective toward E. coli. Instead, colloidal pine showed a weak effect on S. aureus but specificity toward E. coli. The present proof-of-concept points at colloidal polyphenols as valuable alternatives for antimicrobial substitutes in the livestock context.

Exploring the Bioactive Potential of Moroccan Lemon Grass (Cymbopogon citratus L.): Investigations on Molecular Weight Distribution and Antioxidant and Antimicrobial Potentials.

Research on lemon grass (Cymbopogon citratus L.) revealed a variety of active molecules and examined their biological characteristics. However, most of these studies were conducted on wild varieties, while cultivated plants were addressed less. This study aimed to characterize the biomolecules and biological activities of lemon grass growing under North African conditions in Morocco. Phenolic compound profiles of aqueous (AE), ethanol (EE), and methanol (ME) extracts and their fractions were obtained with steric exclusion chromatography on Sephadex G50 gel and identified by LC-MS/MS. Then, total polyphenols (TPC), flavonoids (TFC), and antioxidant activities (FRAP: scavenging value and TAC: Total Antioxidant Capacity) of the fraction were evaluated, as well as the antimicrobial activity. The obtained results showed that the ME contained eight major compounds (i.e., apigenine-7-O-rutinoside and myricitine-3-O-rutinoside). The AE showed the presence of five molecules (i.e., kaempferol-3-O-glucuronide), while EE showed the presence of three molecules (i.e., quercetine-3-O-rutinoside). Regarding the chemical characterization, the highest value of total phenolic content (TPC) was obtained in AE (25) (4.60 ± 0.29 mg/g), and the highest value of total flavonoid content (TFC) was obtained in ME (29) (0.7 ± 0.08 mg/g). Concerning the antioxidant activity, the highest FRAP was obtained in ME (29) (97.89%), and the highest total antioxidant capacity (TAC) was obtained in ME (29) (89.89%). Correlation between FRAP, TPC, and TFC was noted only in fractions of AE and ME. All tested extracts of C. citratus and their fractions showed a significant antimicrobial effect. The lowest minimum inhibitory concentration (MIC) was recorded for ME against E. coli. Extracts' biological activities and their fractions were governed by their active molecules. These data are new and clarify a novel aspect of bioactive molecules in the extracts of cultivated C. citratus. Equally, throughout this research, we clarified the relationship between identified molecules and their biological properties, including antioxidant and anti-microbial activities, which is new for the study area. This study is suggested as a reference for comparative studies and other assays of other biological activities for the study plant.

Novel eco-friendly and easily recoverable bismuth-based materials for capturing and removing polyphenols from water.

Olive oil production is one of the most developed Europe's sectors, producing olive oil and undesirable by-products, such as olive mill wastewater (OMWW) and organic waste. OMWW, containing large amounts of compounds (mainly polyphenols, phenols, and tannins), represents a problem. In fact, polyphenols have dual nature: i) antioxidant beneficial properties, useful in many industrial fields, ii) biorefractory character making them harmful in high concentrations. If not properly treated, polyphenols can harm biodiversity, disrupt ecological balance, and degrade water quality, posing risks to both environment and human health. From a circular economy viewpoint, capturing large quantities of polyphenols to reuse and removing their residuals from water is an open challenge. This study proposes, for the first time, a new path beyond the state-of-the-art, combining adsorption and degradation technologies by novel, eco-friendly and easily recoverable bismuth-based materials to capture large amounts of two model polyphenols (gallic acid and 3,4,5-trimethoxybenzoic acid), which are difficult to remove by traditional processes, and photodegrade them under solar light. The coupled process gave rise to collect 98% polyphenols, and to rapidly and effectively photodegrade the remaining portion from water.

Tannic acid elicits differential gene regulation in prostate cancer apoptosis.

Prostate cancer is a significant global health concern that requires innovative therapeutic investigations. Here, the potential anticancer properties of tannic acid were evaluated by examining its effects on apoptosis in prostate cancer cell lines. PC-3 and LnCaP prostate adeno carcinoma cells, along with PNT1A prostate control cells, were cultured and divided into untreated and tannic acid-treated groups. Cell proliferation, cytotoxicity, and effects of tannic acid on the cell death mechanism were evaluated. mRNA expression levels of 84 genes were explored in cells following tannic acid treatment. Notably, tannic acid-induced down-regulation of several pro-survival genes, including ATM, BCL2, BCL2A1, BIK, BIRC2, BIRC3, BRE, CASP3, CASP6, CASP8, CHEK2, CRADD, PPIA, RPA3, TNFSF18, TRAF1, TRAF2, TRAF4, and TRAF5 in both cell lines. Moreover, tannic acid treatment led to the up-regulation of various pro-apoptotic genes, such as BCL10, BIRC3, BNIP3, CASP1, CASP5, CD40, CIDEB, DAPK2, FASLG, GADD45A, MYD88, RPA 3, TNFRSF10D, TNFRSF17, TNFRSF8, TNFSF13B, TNFSF4, TNFSF7, TNFSF8, TNFSF9, TP53, TRAF1, and TRAF2 in both PC-3 and LnCap cells. These findings highlight tannic acid's ability to induce apoptosis in prostate cancer cells through pro-apoptotic pathways. This study concludes that tannic acid selectively inhibits prostate cancer cell growth.

Effect of Arthrospira platensis (Spirulina) Fortification on Physicochemical, Nutritional, Bioactive, Textural, and Sensory Properties of Vegan Basil Pesto.

The high protein content of several microalgae species makes them an excellent addition to various food products, increasing their nutritional value. In this study, vegan basil pesto was designed and enriched with 1% and 2% Arthrospira platensis (spirulina). The pesto obtained was characterized by increased protein content (up to 40% more) and had a rich mineral composition, including up to three times more iron and 25% more calcium, among others. The increase of spirulina addition in the pesto also increased the content of polyphenols (up to 50% more) and flavonoids (up to 39% more). The fortified products had higher antioxidant activity against ABTS (up to 484.56 ± 2.16 µM Trolox/g) and DPPH (up to 392.41 ± 13.58 µM Trolox/g). The addition of spirulina will affect the hardness of the sauce, while in the other texture parameters (adhesiveness, springiness, and cohesion), there were no significant differences between the control and spirulina-fortified pesto. Although the pesto with spirulina was significantly darker in color (ΔE 8.83 and 12.05), consumers still rated it highly. All quality parameters of pesto with a 1% spirulina addition were rated the highest, contributing to the highest overall rating of the product (4.56). An increase in spirulina addition to 2% resulted in a decrease in the overall pesto rating (4.01), but still remains a good result compared to the control (4.22).

Regular Consumption of Green Tea as an Element of Diet Therapy in Drug-Induced Liver Injury (DILI).

The liver is a highly metabolically active organ, and one of the causes of its dysfunction is the damage caused by drugs and their metabolites as well as dietary supplements and herbal preparations. A common feature of such damage is drugs, which allows it to be defined as drug-induced liver injury (DILI). In this review, we analysed available research findings in the global literature regarding the effects of green tea and/or its phenolic compounds on liver function in the context of protective action during prolonged exposure to xenobiotics. We focused on the direct detoxifying action of epigallocatechin gallate (EGCG) in the liver, the impact of EGCG on gut microbiota, and the influence of microbiota on liver health. We used 127 scientific research publications published between 2014 and 2024. Improving the effectiveness of DILI detection is essential to enhance the safety of patients at risk of liver damage and to develop methods for assessing the potential hepatotoxicity of a drug during the research phase. Often, drugs cannot be eliminated, but appropriate nutrition can strengthen the body and liver, which may mitigate adverse changes resulting from DILI. Polyphenols are promising owing to their strong antioxidant and anti-inflammatory properties as well as their prebiotic effects. Notably, EGCG is found in green tea. The results of the studies presented by various authors are very promising, although not without uncertainties. Therefore, future research should focus on elucidating the therapeutic and preventive mechanisms of polyphenols in the context of liver health through the functioning of gut microbiota affecting overall health, with particular emphasis on epigenetic pathways.

Polyphenol-Rich Extract of Apocynum venetum L. Leaves Protects Human Retinal Pigment Epithelial Cells against High Glucose-Induced Damage through Polyol Pathway and Autophagy.

Diabetic retinopathy (DR) is a specific microvascular problem of diabetes, which is mainly caused by hyperglycemia and may lead to rapid vision loss. Dietary polyphenols have been reported to decrease the risk of DR. Apocynum venetum L. leaves are rich in polyphenolic compounds and are popular worldwide for their health benefits as a national tea drink. Building on previous findings of antioxidant activity and aldose reductase inhibition of A. venetum, this study investigated the chemical composition of polyphenol-rich extract of A. venetum leaves (AVL) and its protective mechanism on ARPE-19 cells in hyperglycemia. Ninety-three compounds were identified from AVL by LC-MS/MS, including sixty-eight flavonoids, twenty-one organic acids, and four coumarins. AVL regulated the polyol pathway by decreasing the expression of aldose reductase and the content of sorbitol, enhancing the Na+K+-ATPase activity, and weakening intracellular oxidative stress effectively; it also could regulate the expression of autophagy-related proteins via the AMPK/mTOR/ULK1 signaling pathway to maintain intracellular homeostasis. AVL could restore the polyol pathway, inhibit oxidative stress, and maintain intracellular autophagy to protect cellular morphology and improve DR. The study reveals the phytochemical composition and protective mechanisms of AVL against DR, which could be developed as a functional food and/or candidate pharmaceutical, aiming for retina protection in diabetic retinopathy.

Effects of combined ultrasound and calcium ion pretreatments on polyphenols during mung bean germination: Exploring underlying mechanisms.

Mung beans were pretreated with a combination of ultrasonic and calcium ion to enhance the polyphenol content and antioxidant capacity during germination. Changes in polyphenol content and antioxidant capacity during germination, along with underlying mechanisms, were investigated. Both single ultrasound and combined ultrasound-Ca2+ pretreatments significantly increased the polyphenol content and enhanced the antioxidant capacity (p < 0.05) of mung beans depending on germination period. Among 74 polyphenolic metabolites identified in germinated mung beans, 50 were differential. Notably, 23 of these metabolites showed a significant positive correlation with antioxidant activity. Ultrasound pretreatment promoted flavonoid biosynthesis, whereas ultrasound-Ca2+ pretreatment favored the tyrosine synthesis pathway. Polyphenol composition and accumulation changes were mainly influenced by metabolic pathways like flavonoid, isoflavonoid, anthocyanin, and flavone/flavonol biosynthesis. The results suggest that ultrasound alone or combined with calcium ion pretreatments effectively enhance mung bean polyphenol content and antioxidant capacity during germination.