Polyphenol-rich Extract Research Articles

Polyphenol-rich Ocimum gratissimum leaf extract attenuates angiotensin-converting enzyme activity and impaired endothelial vascular function in diabetic rats

Endothelial vascular dysfunctions are prevalent among diabetic patients, significantly impacting their quality of life and prognosis. This study examined the effects of polyphenol-rich extracts from Ocimum gratissimum leaves on oxidative stress markers, serum lipid profiles, and angiotensin-converting enzyme activity in diabetic cardiac tissue. Forty Wistar rats (150–220 g) were divided into five groups: normal control, diabetic control, low-dose Ocimum gratissimum (122.46 mg/kg), medium-dose Ocimum gratissimum (244.98 mg/kg), and a positive control (standard diabetic drug). All rats except the normal control group were made diabetic via an intraperitoneal injection of 50 mg/kg streptozotocin, followed by 28 days of extract administration. Diabetes induction led to a significant (p<0.05) disruptions in lipid profiles, oxidative stress markers, and ACE activity. Treatment with Ocimum gratissimum extracts at both doses significantly (p<0.05) decreased triglyceride, low-density lipoprotein cholesterol, and very-low-density lipoprotein cholesterol levels while increasing high-density lipoprotein cholesterol. Lipid peroxidation marker, malondialdehyde, was significantly (p<0.05) decreased, and antioxidant enzyme activities significantly (p<0.005) improved. ACE activity was significantly (p<0.05) reduced, approaching control levels. These results suggest that the polyphenol-rich extract of Ocimum gratissimum exerts antioxidant and cardio-protective effects, improving vascular functions in diabetic rats by improving lipid profiles, reducing oxidative stress, and suppressing ACE activity.

Native corn (Zea mays L., cv. ‘Elotes Occidentales’) polyphenols extract reduced total cholesterol and triglycerides levels, and decreased lipid accumulation in mice fed a high-fat diet

Obesity is a complex disease with numerous molecular and metabolic implications that could be prevented through proper diet and lifestyle. Native corn is a promissory underutilized plant species containing bioactive compounds that could reduce the impact of obesity. This research aimed to characterize and evaluate the anti-obesogenic effect of a polyphenols-rich extract of native corn (‘Elotes Occidentales’) in HFD-fed mice. The powdered extract was administered using gelatins to C57BL/6 J mice randomly divided into four groups (n:8/group) for 13 weeks: standard diet (SD) group, HFD group, HFD+200 mg extract/kg body weight (BW), and HFD+400 mg extract/kg BW/day. Ellagic acid, chlorogenic acid, rutin, and kaempferol were the most abundant phenolics (2022.44–4028.43 µg/g). Among the HFD groups, the highest dose of the extracts promoted the lowest BW gain, and fasting triglycerides and cholesterol levels. Moreover, the HFD+400 mg/kg BW group showed the lowest epididymal and subcutaneous adipose tissue weight and adipocytes’ diameter and area between the HFD-treated animals. The extract administration prevented hepatic lipid accumulation. Rutin demonstrated the highest in silico binding affinity with proteins from the AMPK pathway (ACACA, SIRT1, and SREBP1) (-6.70 to −8.70 kcal/mol). Results indicated beneficial effects in alleviating obesity-associated parameters in vivo due to bioactive compounds from native maize extracts.

Rosa canina L. Methanol Extract and Its Component Rutin Reduce Cholesterol More Efficiently than Miglustat in Niemann-Pick C Fibroblasts.

Niemann-Pick type C (NPC) disease is an autosomal recessive lysosomal storage disorder where 95% of the cases are caused by mutations in the Niemann-Pick C1 (NPC1) gene. Loss of function in NPC1 mutants trigger the accumulation of cholesterol in late endo-lysosomes and lysosomal dysfunction. The current study examined the potential of polyphenol-rich methanol extracts from Rosa canina L. (RCME) and two of its components, rutin and quercitrin, to enhance protein trafficking of NPC1 and restore cholesterol levels in fibroblasts derived from NPC patients, in comparison with miglustat, a drug approved in Europe for NPC treatment. Interestingly, RCME improved the trafficking of the compound heterozygous mutant NPC1I1061T/P887L, homozygous mutant NPC1R1266Q, and heterozygous mutant NPC1N1156S between the endoplasmic reticulum and the Golgi and significantly reduced the levels of cellular cholesterol in the cell lines examined. Miglustat did not affect the trafficking of the three NPC1 mutants individually nor in combination with RCME. Markedly, rutin and quercitrin exerted their effects on cholesterol, but not in the trafficking pathway of NPC1, indicating that other components in RCME are implicated in regulating the trafficking of NPC1 mutants. By virtue of its dual function in targeting the trafficking of mutants of NPC1 as well as the cholesterol contents, RCME is more beneficial than available drugs that target substrate reduction and should be therefore considered in further studies for its feasibility as a therapeutic agent for NPC patients.

Unraveling the hepatoprotective and anti-pancreatic cancer potential of Caralluma europaea: a comprehensive in vivo, in vitro and in silico evidence

Caralluma europaea Guss. (C. europaea) is a medicinal plant used for cancer treatment. However, these treatments may be associated with complications that need to be investigated. This work aims to evaluate not only the chemical composition but also the hepatoprotective and anticancer properties of C. europaea extracts. The chemical constitution of the hydroethanolic extract was explored using gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). The hydroethanolic extract, flavonoids, and polyphenols-rich extract at 100, 15, and 50 mg/kg, respectively, were administered to acetaminophen-treated rats for seven days. We used Western blotting and Real-Time quantitative Polymerase Chain Reaction (RT-qPCR) to determine the protein and the mRNA levels of cancer stemness markers in pancreatic cancer cell lines MIA PaCa-2 and BxPC-3 exposed to increasing doses of C. europaea extracts. In silico analysis was used to evaluate the effects of phenolic compounds revealed in C. europaea on caspase-3 and HSP90, and on liver damage on CYP2E1. The primary phenolics detected by GC-MS and HPLC were ferulic acid and benzofurazan. The positive control group showed an increase in AST, ALT, ALP, triglycerides, and VLDL levels. C. europaea extracts demonstrated hepatoprotective effects by ameliorating acetaminophen-induced alterations of biochemical and hispathological parameters. Immunoblotting and RT-qPCR profiling of cancer stemness markers indicated a reduction in the expression levels of Oct-4 and Nanog proteins, as well as a reduction in the mRNA levels of CD133 by 50–60% and Sox2 by 80–90% in pancreatic cancer cells. Molecular docking showed that naringenin presented the highest docking Gscore on CYP2E1 (−8.199) and HSP90 (−7.742). In conclusion, C. europaea extracts could be considered as a safe and promising therapeutic strategy to sensitize pancreatic cancer cells to chemotherapy.

Stabilization of Picea abies Spruce Bark Extracts within Ice-Templated Porous Dextran Hydrogels.

Porous hydrogels have brought more advantages than conventional hydrogels when used as chromatographic materials, controlled release vehicles for drugs and proteins, matrices for immobilization or separation of molecules and cells, or as scaffolds in tissue engineering. Polysaccharide-based porous hydrogels, in particular, can address challenges related to bioavailability, solubility, stability, and targeted delivery of natural antioxidant compounds. Their porous structure enables the facile encapsulation and controlled release of these compounds, enhancing their therapeutic effectiveness. In this context, in the present study, the cryogelation technique has been adopted to prepare novel dextran (Dx)-based porous hydrogels embedding polyphenol-rich natural extract from Picea abies spruce bark (SBE). The entrapment of the SBE within the Dx network was proved by FTIR, SEM, and energy-dispersive X-ray spectroscopy (EDX). SEM analysis showed that entrapment of SBE resulted in denser cryogels with smaller and more uniform pores. Swelling kinetics confirmed that higher concentrations of Dx, EGDGE, and SBE reduced water uptake. The release studies demonstrated the effective stabilization of SBE in the Dx-based cryogels, with minimal release irrespective of the approach selected for SBE incorporation, i.e., during synthesis (~3-4%) or post-synthesis (~15-16%). In addition, the encapsulation of SBE within the Dx network endowed the hydrogels with remarkable antioxidant and antimicrobial properties. These porous biomaterials could have broad applications in areas such as biomedical engineering, food preservation, and environmental protection, where stability, efficacy, and safety are paramount.

Sorghum bicolor polyphenol-rich extract improves insulin sensitivity and protect against chronic stress exacerbated diabetic nephropathy through modulation of Nrf2/NF-κB

IntroductionSorghum bicolor leaf sheath is known for its rich phytoconstituents 3-in deoxyanthocyanidins with protective and health benefits in targeting oxidative stress, inflammation and apoptosis. This study aimed to investigate Sorghum bicolor polyphenol-rich extract (SBPE) and its combination with metformin on insulin resistance and diabetic nephropathy in high-fat/streptozotocin-induced diabetic rats exposed to chronic stress. MethodsAntidiabetic and nephroprotective effects of SBPE was investigated in male Wistar rats fed with high-fat diet and injected streptozotocin (35 mg/kg) intraperitoneally. Diabetic rats were exposed to chronic unpredictable mild stress and orally treated with SBPE (200 mg/kg), metformin (250 mg/kg) and SBPE+metformin for 28 days. Kidney function parameters, FBS, insulin, adiponectin, kidney injury marker (KIM-1), triglycerides were determined. Renal tissues inflammatory (TNF-α, IL-1β, IL-10), oxidative stress, apoptotic (caspase-3,-9) and transcriptional factors (Nrf2 and NF-κB) were determined as well as histology. ResultsSBPE significantly reduced FBS, triglycerides insulin and parameters for insulin resistance in diabetic rats exposed to stress. Dysregulated electrolytes, urea, creatinine, adiponectin and KIM-1 were significantly reversed in SBPE and SBPE+metformin groups. SBPE treatment significantly reduced MDA, nitrites, TNF-α, and IL-1β levels, while GSH, catalase, SOD, GST and IL-10 were increased in renal tissues. Increased apoptotic markers (caspase-3, caspase-9) and NF-κB, along with reduced Nrf2 levels, were significantly reversed by SBPE and SBPE+metformin. Distorted kidney histomorphoarchitecture was reversed in SBPE-treated groups ConclusionSorghum bicolor polyphenol-rich extract and its combination with metformin showed promising antidiabetic effects in stress-exacerbated diabetes in rats through improving insulin sensitivity and nephroprotective mechanisms.

Evaluation of Polyphenol Profile from Citrus Peel Obtained by Natural Deep Eutectic Solvent/Ultrasound Extraction

Citrus fruits are widely consumed worldwide; however, one of their primary uses is juice production, resulting in over 40 million tons of agro-industrial waste. Citrus peel is the main agro-industrial by-product in citrus production. In recent years, secondary metabolites of interest, mainly polyphenols such as hesperidin, have been identified in citrus peels. Currently, green alternatives like natural deep eutectic solvents (NADES) based on choline chloride and glucose (Glu), combined with ultrasound-assisted extraction, are studied to obtain polyphenol-rich extracts with potential health applications. This study aims to evaluate the effect of: (1) molar ratios (MR) of 1:0.5, 1:1 or 1:2 mol/mol of choline chloride (ChCl):glucose (Glu); (2) the percentage of added water (WA: 50, 60 or 70%) to NADES; and (3) different citrus peels of Citrus aurantium (bitter orange), Citrus sinensis (sweet orange), and Citrus limon (lemon) used for extraction, on polyphenol profiles, total polyphenol content (TPC), and antioxidant capacity (Ax) of the extracts. The extracts were analyzed using ultra-performance liquid chromatography (UPLC) and evaluated using the Folin–Ciocalteu method for TPC and DPPH assay for quantifying AC. A factorial experimental design 33 was implemented. The extract obtained with an MR of 1:1 (ChCl:Glu) from Citrus aurantium peel exhibited the highest concentration of hesperidin (2003.37 ± 10.91 mg/100 g dry mass), whereas an MR of 1:2 (ChCl:Glu) exhibited the highest concentration of neohesperidin (1045.94 ± 1.27 mg/100 g dry mass), both using 60% WA. This extract also showed the highest antioxidant capacity, achieving 100% inhibition. On the other hand, the highest concentration of total phenolic content (TPC) (96.23 ± 0.83 mg GAE/100 g dry mass) was obtained using C. aurantium peel with an MR of 1:0.5 (ChCl:Glu) and 60% WA. The extracts also presented high concentrations of rutin and catechin. These findings highlight the potential of revalorizing citrus peels, particularly Citrus aurantium, and their extracts obtained with NADES for possible health applications.

Improving the Extraction of Polyphenols from Cocoa Bean Shells by Ultrasound and Microwaves: A Comparative Study.

The extraction of bioactive compounds from food by-products is one of the most important research areas for the nutraceutical, pharmaceutical, and food industries. This research aimed to evaluate the efficiency of Ultrasound-Assisted Extraction (UAE) and Microwave-Assisted Extraction (MAE), either alone or in combination, of phenolic compounds from cocoa bean shells (CBSs). These extraction techniques were compared with conventional methods, such as under simple magnetic stirring and the Soxhlet apparatus. After the preliminary characterization of the gross composition of CBSs, the total polyphenol content and radical scavenging of extracts obtained from both raw and defatted cocoa bean shells were investigated. Quantification of the main polyphenolic compounds was then performed by RP-HPLC-DAD, identifying flavonoids and phenolic acids, as well as clovamide. The application of MAE and UAE resulted in a similar or superior extraction of polyphenols when compared with traditional methods; the concentration of individual polyphenols was variously influenced by the extraction methods employed. Combining MAE and UAE at 90 °C yielded the highest antiradical activity of the extract. Spectrophotometric analysis confirmed the presence of high-molecular-weight melanoidins, which were present in higher concentrations in the extracts obtained using MAE and UAE, especially starting from raw material. In conclusion, these results emphasize the efficiency of MAE and UAE techniques in obtaining polyphenol-rich extracts from CBS and confirm this cocoa by-product as a valuable biomass for the recovery of antioxidant compounds, with a view to possible industrial scale-up.

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.

Valorization of berry pomace for extraction of polyphenol compounds and its co-encapsulation with probiotic bacteria

Saskatoon berry pomace, an antioxidant rich byproduct, may be suitable for nutraceuticals and functional foods. The present study aimed to co-encapsulate polyphenol-rich berry extract with probiotics to utilize the polyphenolic compounds present in berry pomace. The major benefit of co-encapsulation is that polyphenolic compounds increase the survival characteristics of probiotic bacteria in gastrointestinal tract. To make the process cost-effective, a conventional solvent extraction method was used for extraction of polyphenolic compounds from berry pomace. Spray drying was used to co-encapsulate polyphenols and probiotics by using plant-based carrier materials (pea protein isolate with gum Arabic). Spray dried powder was evaluated for encapsulation efficiency, gastrointestinal stability, bio-accessibility index, along with functional, structural and thermal characteristics. Berry pomace was found to be a good source of TPC, DPPH and ABTS with 2.49 mg GAE/1 g, 4.48 mg QE/1 g and 2.96 mg QE/1 g, respectively. The encapsulation efficiency (retention of polyphenolics and bacteria in capsules) of polyphenolic compounds and probiotics was 72.6% and 94.4%, respectively. Probiotic cells encapsulated with polyphenolic compounds showed improved survival (9.08 log CFU/mL) during in vitro gastrointestinal digestion. The bio-accessibility of TPC was 63.6% after intestinal digestion. The spray dried powder was observed to possess good thermal stability but poor functional properties, thus limiting applications to products such as bakery goods, sports bars, cereals and other foods where dispersibility is not imperative. Therefore, co-encapsulation by spray drying method offers an efficient and cost-effective method for simultaneous delivery of bioactive compounds and probiotics to the gut, extending their benefits by this combination.

Optimization of Polyphenol Extraction Conditions from Rhizomes of Curcuma zedoaria with Antioxidant, Anti-Inflammatory and Anti-Diabetic Activities In Vitro

The recovery of polyphenol compounds is seen as an arduous task because polyphenol compounds are available as free aglycones, as sugar or ester conjugates, or as polymers with several monomeric components. The response surface method (RSM) as a tool to optimize the factors that affect extraction efficacy as well as to obtain maximum recovery of the compounds of interest. This study optimizes ultrasound-assisted polyphenol extraction from Curcuma zedoaria rhizomes using response surface methodology (RSM). Three variables were considered: Ethanol concentration (70 - 90 %, v/v), temperature (60 - 80 °C), and ultrasound time (15 - 25 min). Data were analyzed by ANOVA, yielding an R2 of 0.9993, a significant interaction effect (p < 0.0001), and an insignificant lack-of-fit test (p = 0.6684). Optimal conditions for maximum polyphenol content (TPC = 31.05 ± 0.53 mg GAE/g powder) were 80.02 % ethanol, 68 °C, 20.47 min ultrasound time, and 1/10 (w/v) raw material/solvent ratio. Experimental values matched RSM predictions, confirming successful extraction optimization from Curcuma zedoaria rhizomes. The polyphenol-rich optimum extract from Curcuma zedoaria rhizomes has been studied for its antioxidant, anti-inflammatory and anti-inflammatory properties in vitro. The results were found, the optimum extract of Curcuma zedoaria rhizomes could perform effective neutralization activities of free radicals performed in DPPH test (IC50 = 5.89 ± 0.23 µg/mL), NO· (IC50 = 5.89 ± 0.23 µg/mL) and ABTS·+ (IC50 = 8.28 ± 0.12 µg/mL). Besides, this optimum extract had the ability to protect red blood cell membranes and inhibit protein denaturation due to heat with IC50 times values ​​such as 29.06 ± 0.35 and 30.24 ± 0.32 µg/mL. In addition, it also significantly inhibited α-amylase, α-glucosidase enzyme activities with IC50 values ​​of 5.89 ± 0.23 and 9.62 ± 0.11 μg/mL, respectively. This investigation showed that the polyphenol-rich optimum extract from Curcuma zedoaria rhizomes was a promising antioxidant, anti-inflammatory and anti-diabetic agent. HIGHLIGHTS Using ultrasound and the Box-Behnken design to extract polyphenols from Curcuma zedoaria rhizomes can speed up and improve extraction efficiency. The goal of this study is to maximize the extraction parameters for polyphenols from the rhizomes of Curcuma zedoaria. There is strong agreement between the experimental data and the model that predicts the polyphenol content in the Box-Behnken design. In vitro biological activities such as anti-inflammatory, antidiabetic and antioxidant properties are significantly correlated with polyphenol concentration. The findings of our investigation show a noteworthy enhancement in the bioavailability of polyphenol compounds through increased extraction efficiency and bioactivity. GRAPHICAL ABSTRACT

Emulsification capacity of pectin extracts from persimmon waste: Effect of structural characteristics and pectin-polyphenol interactions

Polyphenol-rich pectin extracts obtained from persimmon waste might have great potential due to their emulsification capacity. Their emulsion stabilizing properties may be influenced by pectin molecular structure and pectin-polyphenol interactions which in turn can be determined by the extraction conditions. Hence, this work aimed to study the influence of the molecular structure characteristics and their respective pectin-polyphenol interactions of three polyphenol-rich persimmon pectin extracts obtained by three different extraction conditions. Low, medium and high severity extraction conditions resulted in covalent phenolics-extract (CP-E), non-covalent phenolics-extract (NCP-E) and free phenolics-extract (FP-E), respectively. The electrical charge of pectin was strongly dependent on the pH, becoming more negative at increasing pH due to carboxyl group dissociation. CP-E and NCP-E in solution had more expanded conformations than FP-E, with greater intermolecular distances and hydrodynamic diameters ranging from 1089 to 1791 nm for CP-E and NCP-E, whereas from 529 to 782 nm for FP-E. Their interfacial layer thickness was thicker at pH 3 than at pH 7, probably due to multilayer organization as a result of less repulsion between pectin chains. All pectin extracts were able to decrease the interfacial tension of an oil droplet from 35 to at least 25 mN/m, with FP-E at pH 3 being the most efficient (13.89 ± 1.07 mN/m). Even so, submicron O/W emulsions with negative ζ-potential values could be formed with all pectin extracts. However, CP-E rendered O/W emulsions with higher colloidal stability than FP-E or NCP-E, which showed aggregation and creaming. These findings provide novel insights to re-valorize pectin from persimmon waste.

Artichoke By-Product Extracts as a Viable Alternative for Shelf-Life Extension of Breadsticks.

The upcycling of agricultural by-products and the extension of the shelf-life of staple foods represent crucial strategies for mitigating the consequences of food losses and enhancing the competitiveness of the agri-food industry, thus facilitating the attainment of higher financial revenues. This is particularly relevant for global artichoke cultivation, where 60-80% of its biomass is discarded annually. The present study investigated the potential of using non-stabilized polyphenol-rich extracts from the main artichoke by-products (bracts, leaves, and stems) to fortify and extend the shelf-life of breadsticks. The incorporation of hydroalcoholic extracts at two addition levels (1000-2000 ppm) resulted in an increased antioxidant capacity and oxidative stability of fortified breadsticks. Rheological tests revealed that the fortification did not affect the dough's workability, with the exception of the leaf extract. While a slight deterioration in texture was observed, the shelf-life of breadsticks was significantly extended, particularly at the highest levels of addition, without any visible alteration in their appearance. The stem extract demonstrated the most promising outcomes, exhibiting a maximum increase of 69% in antioxidant capacity (DPPH) and an extension of the estimated shelf-life by 62% in the resulting breadsticks, prompting the potential for utilizing them to develop nutritious and healthy snacks with extended shelf-life.

Sustainable experimental cultivation of the Greek endemic Helichrysum amorginum Boiss. and Orph.: Assessment of the total phenolic content at different flower harvest stages

Helichrysum amorginum Boiss. and Orph. constitutes a range-restricted, endemic species of Greece with known pharmaceutical potency. The current work presents the results of a targeted evaluation of the total phenolic content (TPC) of methanolic extracts of H. amorginum flower heads under cultivation conditions at three consecutive harvest stages in two separate cultivation locations across a period of two years (2018 and 2019). The harvested inflorescence tissue was assessed for TPC via the Folin–Ciocalteu method in three and four-year old H. amorginum individuals. Older plants, during the second evaluation year, generally showed higher flower TPC content throughout. The pooled analysis of the results indicated significant differences in TPC among samples of extracts prepared with plant material from different harvest stages with the early flowering stage (A) presenting higher TPC in both experimental cultivation locations (142.6-156 mg GAE g-1 extract on average among the two cultivation locations) followed by the full bloom stage (B) (139-145.7 mg GAE g-1 extract on average) and the late bloom or early post-anthesis stage (C) which showed the lowest TPC in all cases (130.3-131 mg GAE g-1 extract on average). The current results provide for the first-time basic information on the optimum inflorescence harvest stage during the prolonged flowering period of cultivated H. amorginum in terms of TPC. The proposed work can be incorporated into the establishment of a sustainable cultivation protocol for achieving polyphenol-rich extracts and ultimately contributes to the utilization of H. amorginum in the pharmaceutical/cosmetic sectors.

Camu-camu decreases hepatic steatosis and liver injury markers in overweight, hypertriglyceridemic individuals: A randomized crossover trial

Non-alcoholic fatty liver disease (NAFLD) affects 25% of the adult population with no effective drug treatments available. Previous animal studies reported that a polyphenol-rich extract from the Amazonian berry camu-camu (CC) prevented hepatic steatosis in a mouse model of diet-induced obesity. This study aims to determine the impact of CC on hepatic steatosis (primary outcome) and evaluate changes in metabolic and gut microbiota profiles (exploratory outcomes). A randomized, double-blind, placebo-controlled crossover trial is conducted on 30 adults with overweight and hypertriglyceridemia, who consume 1.5g of CC capsules or placebo daily for 12weeks. CC treatment decreases liver fat by 7.43%, while it increases by 8.42% during the placebo intervention, showing a significant difference of 15.85%. CC decreases plasma aspartate and alanine aminotransferases levels and promotes changes in gut microbiota composition. These findings support that polyphenol-rich prebiotic may reduce liver fat in adults with overweight, reducing the risk of developing NAFLD.

Intestinal epithelial differentiation and barrier function is promoted in vitro by a Cynara cardunculus L. leaf extract through AMPK pathway activation

Gut epithelial barrier perturbation leads to leaky gut syndrome and permeation of substances activating immune response. Polyphenols can improve intestinal barrier function and represent candidates for preventing development of leaky gut. Herein, we evaluated in vitro the molecular mechanisms involved in the protective effects of a polyphenol-rich extract from leaves of Cynara cardunculus L. (CCLE) on intestinal barrier function and integrity on Caco-2 human epithelial cells. Treatment with CCLE from seeding until complete differentiation improved intestinal function by increasing trans-epithelial electrical resistance (TEER), reducing paracellular permeability to fluorescein, and promoting faster recovery of tight junctions (TJ) assembly in the Ca2+ switch assay. CCLE stimulated epithelial cell differentiation inducing alkaline phosphatase activity and TJ proteins. These CCLE-induced effects were attributed to activation of AMP-activated protein kinase (AMPK) pathway. Our data support the use of Cynara cardunculus L. leaves, an agricultural co-product rich in bioactive polyphenols, for the health of intestinal epithelium.

Anti-staphylococcal activity of a polyphenol-rich citrus extract: synergy with β-lactams and low proficiency to induce resistance.

Antibiotic resistance represents one of the most significant threats to public health in the 21st century. Polyphenols, natural molecules with antibacterial activity produced by plants, are being considered as alternative antimicrobial strategies to manage infections caused by drug-resistant bacteria. In this study, we investigated the antibacterial activity of a polyphenol mixture extracted from citrus fruits, against both antibiotic-susceptible and resistant strains of Staphylococcus aureus and Staphylococcus epidermidis. Broth microdilution and time-kill curve experiments were used to test the extract anti-staphylococcal activity. Cytotoxicity was assessed by the hemolysis assay. The interaction between the mixture and antibiotics was investigated by the checkerboard assay. The effect of B alone and in combination with oxacillin on the membrane potential was investigated by the 3,3'-dipropylthiadicarbocyanine iodide assay. The ability of the extract to induce the development of resistance was verified by propagating S. aureus for 10 transfers in the presence of sub-inhibitory concentrations. The citrus extract was found to be active against all Staphylococcus strains at remarkably low concentrations (0.0031 and 0.0063%), displaying rapid bactericidal effects without being toxic on erythrocytes. In particular, B was found to rapidly cause membrane depolarization. When combined with methicillin, meropenem, and oxacillin, the mixture displayed synergistic activity exclusively against methicillin-resistant strains. We additionally show that the sequential exposure of S. aureus to sub-inhibitory concentrations did not induce the development of resistance against the extract. Overall, these findings support the potential use of the citrus extract as promising option to manage staphylococcal infections and suggest that it may counteract the mechanism behind methicillin-resistance.

Polyphenol-rich extract from Sanghuangporous vaninii against acetaminophen-induced liver injury by blocking ferroptosis via NRF2/GPX4 pathway

Polyphenol-rich extract from <em>Sanghuangporous vaninii</em> against acetaminophen-induced liver injury by blocking ferroptosis via NRF2/GPX4 pathway

Targeting senescence induced by age or chemotherapy with a polyphenol-rich natural extract improves longevity and healthspan in mice

Accumulating senescent cells within tissues contribute to the progression of aging and age-related diseases. Botanical extracts, rich in phytoconstituents, present a useful resource for discovering therapies that could target senescence and thus improve healthspan. Here, we show that daily oral administration of a standardized extract of Salvia haenkei (Haenkenium (HK)) extended lifespan and healthspan of naturally aged mice. HK treatment inhibited age-induced inflammation, fibrosis and senescence markers across several tissues, as well as increased muscle strength and fur thickness compared with age-matched controls. We also found that HK treatment reduced acutely induced senescence by the chemotherapeutic agent doxorubicin, using p16LUC reporter mice. We profiled the constituent components of HK by mass spectrometry, and identified luteolin—the most concentrated flavonoid in HK—as a senomorphic compound. Mechanistically, by performing surface plasmon resonance and in situ proximity ligation assay, we found that luteolin disrupted the p16–CDK6 interaction. This work demonstrates that administration of HK promotes longevity in mice, possibly by modulating cellular senescence and by disrupting the p16–CDK6 interaction.

Antimicrobial Potential of Pomegranate and Lemon Extracts Alone or in Combination with Antibiotics against Pathogens.

Amidst the growing concern of antimicrobial resistance as a significant health challenge, research has emerged, focusing on elucidating the antimicrobial potential of polyphenol-rich extracts to reduce reliance on antibiotics. Previous studies explored the antifungal effects of extracts as potential alternatives to conventional therapeutic strategies. We aimed to assess the antibacterial and antifungal effects of standardised pomegranate extract (PE) and lemon extract (LE) using a range of Gram-negative and Gram-positive bacteria and two yeast species. Additionally, we assessed the antimicrobial activities of common antibiotics (Ciprofloxacin, Imipenem, Gentamicin, and Ceftazidime), either alone or in combination with extracts, against Staphylococcus aureus and Escherichia coli. PE displayed substantial antibacterial (primarily bactericidal) and antifungal effects against most pathogens, while LE exhibited antibacterial (mostly bacteriostatic) and antifungal properties to a lesser extent. When compared with antibiotics, PE showed a greater zone of inhibition (ZOI) than Ciprofloxacin and Ceftazidime (p < 0.01) and comparable ZOI to Gentamicin (p = 0.4) against Staphylococcus aureus. However, combinations of either PE or LE with antibiotics exhibited either neutral or antagonistic effects on antibiotic activity against Staphylococcus aureus and Escherichia coli. These findings contribute to the existing evidence regarding the antimicrobial effects of PE and LE. They add to the body of research suggesting that polyphenols exert both antagonistic and synergistic effects in antimicrobial activity. This highlights the importance of identifying optimal polyphenol concentrations that can enhance antibiotic activity and reduce antibiotic resistance. Further in vivo studies, starting with animal trials and progressing to human trials, may potentially lead to recommendation of these extracts for therapeutic use.