Polyphenol-rich Extract Research Articles

Encapsulation of Olive Leaf Polyphenol-Rich Extract in Polymeric Micelles to Improve Its Intestinal Permeability.

In the present study, polymeric micelles were developed to improve the intestinal permeability of an extract of Olea europaea L. leaf with a high content of total polyphenols (49% w/w), with 41% w/w corresponding to the oleuropein amount. A pre-formulation study was conducted to obtain a stable formulation with a high loading capacity for extract. The freeze-drying process was considered to improve the stability of the formulation during storage. Micelles were characterized in terms of physical and chemical properties, encapsulation efficiency, stability, and in vitro release. The optimized system consisted of 15 mg/mL of extract, 20 mg/mL of Pluronic L121, 20 mg/mL of Pluronic F68, and 10 mg/mL of D-α-tocopheryl polyethylene glycol succinate (TPGS), with dimensions of 14.21 ± 0.14 nm, a polydisersity index (PdI) of 0.19 ± 0.05 and an encapsulation efficiency of 66.21 ± 1.11%. The influence of the micelles on polyphenol permeability was evaluated using both Parallel Artificial Membrane Permeability Assay (PAMPA) and the Caco-2 cell monolayer. In both assays, the polymeric micelles improved the permeation of polyphenols, as demonstrated by the increase in Pe and Papp values.

Lavandula pedunculata Polyphenol-Rich Extracts Obtained by Conventional, MAE and UAE Methods: Exploring the Bioactive Potential and Safety for Use a Medicine Plant as Food and Nutraceutical Ingredient.

Nowadays, plant-based bioactive compounds (BCs) are a key focus of research, supporting sustainable food production and favored by consumers for their perceived safety and health advantages over synthetic options. Lavandula pedunculata (LP) is a Portuguese, native species relevant to the bioeconomy that can be useful as a source of natural BCs, mainly phenolic compounds. This study compared LP polyphenol-rich extracts from conventional maceration extraction (CE), microwave and ultrasound-assisted extraction (MAE and UAE). As a result, rosmarinic acid (58.68-48.27 mg/g DE) and salvianolic acid B (43.19-40.09 mg/g DE) were the most representative phenolic compounds in the LP extracts. The three methods exhibited high antioxidant activity, highlighting the ORAC (1306.0 to 1765.5 mg Trolox equivalents (TE)/g DE) results. In addition, the extracts obtained with MAE and CE showed outstanding growth inhibition for B. cereus, S. aureus, E. coli, S. enterica and P. aeruginosa (>50%, at 10 mg/mL). The MAE extract showed the lowest IC50 (0.98 mg DE/mL) for angiotensin-converting enzyme inhibition and the best results for α-glucosidase and tyrosinase inhibition (at 5 mg/mL, the inhibition was 87 and 73%, respectively). The LP polyphenol-rich extracts were also safe on caco-2 intestinal cells, and no mutagenicity was detected. The UAE had lower efficiency in obtaining LP polyphenol-rich extracts. MAE equaled CE's efficiency, saving time and energy. LP shows potential as a sustainable raw material, allowing diverse extraction methods to safely develop health-promoting food and nutraceutical ingredients.

Polyphenol rich sugarcane extract (PRSE) has potential antiviral activity against influenza A virus in vitro

Influenza A virus (IAV) is one of the major global public health concerns but the emerging resistance of IAV to currently available antivirals requires the need to identify potential alternatives. Polyphenol rich sugarcane extract (PRSE) is an extract prepared from the sugarcane plant Saccharum Officinarum. Herein we aimed to determine if PRSE had antiviral activity against IAV. We showed that treatment of IAV-infected cells with PRSE results in a dose-dependent inhibition of virus infection at concentrations that were non-cytotoxic. PRSE treatment limited the early stages of infection, reducing viral genome replication, mRNA transcription and viral protein expression. PRSE did not affect the ability of IAV to bind sialic acid or change the morphology of viral particles. Additionally, PRSE treatment attenuated the replication of multiple IAV strains of the H3N2 and H1N1 subtype. In conclusion, we show that PRSE displays antiviral activity against a broad range of IAV strains, in vitro.

Totum-070, a Polyphenol-Rich Plant Extract, Prevents Hypercholesterolemia in High-Fat Diet-Fed Hamsters by Inhibiting Intestinal Cholesterol Absorption.

Atherosclerotic cardiovascular disease is the leading cause of mortality worldwide, and hypercholesterolemia is a central risk factor for atherosclerosis. This study evaluated the effects of Totum-070, a plant-based polyphenol-rich supplement, in hamsters with high-fat diet (HFD)-induced dyslipidemia. The molecular mechanisms of action were explored using human Caco2 enterocytes. Totum-070 supplementation reduced the total cholesterol (-41%), non-HDL cholesterol (-47%), and triglycerides (-46%) in a dose-dependent manner, compared with HFD. HFD-induced hepatic steatosis was also significantly decreased by Totum-070, an effect associated with the reduction in various lipid and inflammatory gene expression. Upon challenging with olive oil gavage, the post-prandial triglyceride levels were strongly reduced. The sterol excretion in the feces was increased in the HFD-Totum-070 groups compared with the HFD group and associated with reduction of intestinal cholesterol absorption. These effects were confirmed in the Caco2 cells, where incubation with Totum-070 inhibited cholesterol uptake and apolipoprotein B secretion. Furthermore, a microbiota composition analysis revealed a strong effect of Totum-070 on the alpha and beta diversity of bacterial species and a significant decrease in the Firmicutes to Bacteroidetes ratio. Altogether, our findings indicate that Totum-070 lowers hypercholesterolemia by reducing intestinal cholesterol absorption, suggesting that its use as dietary supplement may be explored as a new preventive strategy for cardiovascular diseases.

POLYPHENOL-RICH LEAF EXTRACT OF Moringa oleifera Lam. ATTENUATES NEPHROTOXICITY AND OXIDATIVE STRESS IN CARBON TETRACHLORIDE (CCl )- 4 TREATED ALBINO RATS

This study evaluated the effect of polyphenol-rich leaf extract of Moringa oleifera (PRE-M. o) in carbon tetrachloride (CCl4)-induced nephrotoxic rats. Thirty-six (36) male albino rats were randomly divided into 6 groups. Groups one to six received 1mL/kg olive oil (normal group), 1mL/kg CCl4 (toxicity control group), N-acetyl cysteine with 1mL/kg CCl4, 50mg/kg PRE-M. o with 1mL/kg CCl4, 100mg/kg PRE-M. o with 1mL/kg CCl4 and 250mg/kg PRE-M. o with 1mL/kg CCl4. PRE-M o was administered orally, once daily for seven days while CCl4 prepared in olive oil was administered intraperitoneally on day seven. Twenty-four hours after, animals were sacrificed and Kidneys were dissected for histology, kidney homogenates were prepared and blood samples were collected for biochemical and antioxidant parameters. Effects were investigated using biochemical indices of renal function and oxidative stress. Total phenol, which was quantified in the extract and expressed as mgGAE/g increased with increasing concentrations of the extract. CCl4 caused a significant increase in serum creatinine, urea and uric acid concentrations as well as a significant decrease in total protein and albumin. Malondialdehyde increased while Glutathione (GSH) and superoxide dismutase (SOD) decreased significantly in the CCl4-treated rats. Histopathological study revealed altered glomerular and tubular architecture with noticeable interstitial haemorrhage and infiltration of inflammatory cells in kidney of rats exposed to CCL4. Treatment with PRE-M. o was able to significantly revert all altered parameters which showed that PRE-M. o can restore altered kidney function and ameliorate oxidative stress.

Designing and fabrication of colloidal nano-phytosomes with gamma-oryzanol and phosphatidylcholine for encapsulation and delivery of polyphenol-rich extract from pomegranate peel

Nano-carriers are well-known delivery systems to encapsulate different bioactive compounds and extracts. Such nano-systems are used in various food and drug areas to protect active ingredients, increase bioavailability, control the release, and deliver bioactive substances. This study aimed to design and fabricate a stable colloidal nano-delivery system to better preserve the antioxidant properties of pomegranate peel extract (PPE) and protect its sustained release in a gastrointestinal model. To achieve this goal, a nano-phytosomal system was fabricated with plant-based, cost-effective, and food-grade compounds, i.e., phosphatidylcholine (PC) and gamma-oryzanol (GO) for encapsulation of PPE. To fabricate the nano-phytosomes, thin film hydration/sonication method was used. The parameters of particle size, zeta potential, polydispersity index (PDI), loading capacity (LC), and encapsulation efficiency (EE) were investigated to evaluate the efficiency of the produced nano-system. In summary, the size, zeta potential, PDI, LC, and EE of homogenous spherical PC-GO-PPE nano-phytosomes (NPs) in the ratio of 8:2:2 % w/w were achieved as 60.61 ± 0.81 nm, −32.24 ± 0.84 mV, 0.19 ± 0.01, 19.13 ± 0.30 %, and 95.66 ± 1.52 %, respectively. Also, the structure of NPs was approved by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM). The optimized NPs were stable during one month of storage at 4 °C, and changes in the size of particles and PPE retention rate were insignificant (p > 0.05). The nano-encapsulation of PPE significantly decreased the loss of its antioxidant activity during one month of storage at 4 °C. The optimized NPs exhibited prolonged and sustained release of PPE in a gastrointestinal model, so that after 2 h in simulated gastric fluid (SGF) and 4 h in simulated intestinal fluid (SIF), 22.66 ± 2.51 % and 69.33 ± 4.50 % of initially loaded PPE was released, respectively. Optimized NPs had considerable cytotoxicity against the Michigan Cancer Foundation-7 cell line (MCF7) (IC50 = 103 μg/ml), but not against Human Foreskin Fibroblast cell line (HFF-2) (IC50 = 453 μg/ml). In conclusion, spherical PC-GO-PPE NPs were identified as a promising delivery system to efficiently encapsulate PPE, as well as protect and preserve its bioactivity, including antioxidant and cytotoxicity against cancer cell line.

Polyphenol-rich extract of <I>Digitaria exilis</i> (Kippist) grain lowers gastrointestinal dysmotility and enhanced colonic peristalsis in rifaximin-induced constipated rat

Digitaria exilis grains rich in polyphenol have been speculated among some traditional practitioners of Northern Nigeria to aid in treating constipation. Hence, this study aims at assessing the anti-constipation property of polyphenol-rich extract of Digitaria exilis grains (PREDEG) in rifaximin-induced constipated rat. Thirty (30) Wistar rats of both sexes (143.84 ± 2.62 g) were assigned into 6 categories, A to F, of 5 rats each. Category A (control) received 0.4 ml of saline. Constipations were induced in categories B to F by oraladministration of rifaximin (2 mg/kg in saline for 48 h) and treated respectively with saline, glycerine (reference drug at 40 mg/kg), 50, 150 and 250 mg/kg of PREDEG (extracted via standard methods). All the treatments were given orally for 6 days using oral device. Rifaximin-induced constipation significantly (p < 0.05) decreases the feed and water intake, faecal quality, bodyweight and gastrointestinal flow proportion. All these alterations were attenuated dose-dependently, when co-treated with PREDEG and highest activity recorded at 250 mg/kg compared to reference drug. The data present polyphenol-rich extract of D. exilis grains as a potent anti-constipation agent and may act probably by lowering gastrointestinal dysmotility. This validates its traditional use in the treatment of constipation mostly in the Northern part of Nigeria.

Polygoni Cuspidati Rhizoma et Radix extract attenuates high-fat diet-induced NAFLD in rats: Impact on untargeted serum metabolomics and liver lipidomics

BackgroundPolygoni Cuspidati Rhizoma et Radix (PCRR; the root and rhizome of Polygonum cuspidatum Sieb. et Zucc) has long been used to treat atherosclerosis, gastrointestinal disorders, and liver disease. However, the underlying mechanism of PCRR against liver steatosis remains unclear. PurposeThe aim of this study was to determine the potential therapeutic targets and molecular mechanisms of PCRR in improving liver steatosis. MethodsA high-fat diet (HFD)-induced simple steatosis model in rats was used to evaluate the therapeutic effect of polyphenol-rich water extract from PCRR. Its underlying mechanisms were revealed using untargeted mass spectrometry-based serum metabolomics, hepatic lipidomic profiling approaches, qPCR, and Western blotting assays. ResultsOur study showed that PCRR-treated rats displayed significant reduction of serum TC and LDL-C, hepatic TG, TC levels, and total liver lipid content under a HFD feeding condition. Untargeted metabolomics showed that PCRR significantly restored the overall levels of nine lipid classes in liver tissues and elevated the bile acid levels in the serum samples. We demonstrated that PCRR prevented HFD-induced hepatic steatosis by regulating the expressions of TG metabolism proteins, including p-AMPK, p-ACC, PPARα, and FAS, as well as the expressions of TC metabolism proteins, including p-AMPK, LDLR, and CYP7A1. Moreover, resveratrol and/or polydatin­-derived metabolites were solely detected in the serum samples of the PCRR-treated group, indicating these microbial transformed metabolites might partly contribute to the beneficial effects of PCRR. ConclusionPCRR can be employed as a therapeutic agent to improve non-alcoholic fatty liver disease via regulating lipid metabolism.

Edible Red Seaweed Hypnea asiatica Ameliorates High-Fat Diet-Induced Metabolic Diseases in Mice.

Metabolic diseases, including obesity, diabetes, and fatty liver disease, are dramatically increasing around the world. Seaweed is low in calories and rich in many active ingredients that are necessary for maintaining good health, and is expected to be effective for preventing metabolic diseases. The purpose of this study was to examine the effects of a traditional Japanese edible seaweed Hypnea asiatica (H. asiatica) on obesity, using a mouse model. H. asiatica was dried and powdered, mixed with a high-fat diet, and fed to male C57BL/6J mice for 13 weeks. On the last day of the experiment, blood samples were collected under anesthesia and biochemical parameters such as lipids and adipokines were measured. Liver and adipose tissue were excised, weighed, and oxidant/antioxidant parameters were measured. Some mice were perfused with a fixative solution containing formalin, and tissue specimens were prepared. A glucose tolerance test was used to assess insulin resistance. The inhibition of lipase activity was evaluated in vitro. Thirteen-week supplementation with H. asiatica suppressed body weight gain, body fat accumulation, and blood glucose levels. H. asiatica also improved fatty liver and hypercholesterolemia, and reduced the oxidant and inflammatory parameters of serum and liver. H. asiatica increased fecal triglyceride excretion and polyphenol-rich ethanol extract of H. asiatica inhibited lipase activity in vitro. These results suggest that polysaccharides and polyphenols in H. asiatica may ameliorate obesity and diabetes by inhibiting intestinal fat absorption and reducing oxidative stress and inflammation. H. asiatica may be useful in preventing metabolic diseases such as obesity, diabetes, and fatty liver.

ROS Modulate Cell Death Mechanism in Cervical Cancer Cells Treated with the Combination of Polyphenolic Compounds and Anticancer Drug Cisplatin: A Review

Background: Most cervical cancer fatalities have been reported due to drug resistance, invasion, and metastasis. Combination therapy is a prominent technique for overcoming the toxicity of cancer chemotherapy to normal cells, which is mediated across numerous targeted pathways and requires a lower dose of each individual agent. Polyphenolic substances have the potential to improve chemotherapy efficacy while also reducing negative effects. Aims: This study aimed to review the research findings on the role of reactive oxygen species (ROS) in cervical cancer cell HeLa treated with combination therapy. Results: Hydroxyl radicals damage DNA, causing a cascade of structural changes in purine and pyrimidine bases that could lead to mutagenicity. ROS, such as hydroxyl radical (OH-), superoxide anions (O2 -), hydrogen peroxide (H2O2), and peroxyl radicals (ROO-), are frequent products of aerobic metabolism that can be beneficial or detrimental to the biological system. To combat the harmful effects of ROS, cells have an antioxidative defense system that comprises superoxide dismutases, catalase, glutathione, and other defensive mechanisms. Excessive ROS accumulation causes DNA damage, which triggers the apoptotic machinery, resulting in cell death. Conclusion: Chemotherapeutic medications with phenolic compounds or polyphenol-rich extracts exhibit anticancer synergy. Combination treatment with polyphenols and anticancer drugs is one of the promising approaches in the treatment of cervical cancer.

Tuning the mechanical properties of pectin films with polyphenol-rich plant extracts

The mechanical properties of pectin films enhanced with polyphenol-rich fruit extracts were investigated. The scavenging and reducing activity of plant extracts incorporated into the pectin films were determined using bench assays, and their antioxidant activity was correlated with a high presence of polyphenols, which were predominantly comprised of flavonoids and anthocyanins. The pectin films generated from the extracts exhibited a range of mechanical properties; tensile strength (4.99 MPa – 6.91 MPa), elongation at break (45.8 % - 52.3 %), and stiffness (1835 g mm−1 - 2765 g mm−1). To investigate the underlying relationships between plant extract composition and mechanical properties, Projection to Latent Structures (PLS) models were developed. The PLS models revealed that extracts containing high sugar and polyphenol content increase the tensile strength and moisture content of films. The elongation at break of the films was improved or diminished depending on the profile of sugar, acids, and polyphenols in the fruit extracts. Furthermore, the structures and concentration of anthocyanins and flavonoids were identified to strongly influenced the elongation at break differences. By modifying the concentration of sugars, organic acids, and polyphenols, the mechanical properties of pectin-based films can be tuned for tailored applications as food packaging materials.

Effect of an Oral Formulation on Skin Lightening: Results from In Vitro Tyrosinase Inhibition to a Double-Blind Randomized Placebo-Controlled Clinical Study in Healthy Asian Participants

Oral formulations with natural plant-based extracts represent a safe and promising strategy for skin lightening and anti-dark-spot effects, especially in Asia. This study evaluated the effect of an oral formulation including polyphenol-rich extracts and vitamin C (Belight3TM) on in vitro tyrosinase inhibitory activity and investigated its skin lightening and anti-dark-spot effects in vivo. Tyrosinase inhibitory activity of the formulation was measured with spectrophotometry. A randomized, double-blind, placebo-controlled clinical study was carried out on 58 healthy Asian males and females, aged 45–65. Skin color was measured at baseline, 6 weeks and 12 weeks with digital photographs. Color of dark spots was assessed with spectrophotometry. In vitro, the formulation showed a significant synergistic tyrosinase inhibitory activity of 85% compared to the control. In vivo, 12-week oral administration of the formulation significantly lightened the skin and was significantly better than the placebo. In addition, this formulation induced a slight and significant lightening effect of the dark spots after 6 and 12 weeks. Our findings suggest that the daily oral administration of Belight3TM during 12 weeks appears as an efficient and safe nutricosmetic to lighten the color of the facial skin and dark spots in Asian subjects.

Optimizing the Integration of Microwave Processing and Enzymatic Extraction to Produce Polyphenol-Rich Extracts from Olive Pomace.

The integration of green technologies such as microwave- and enzyme-assisted extraction (MEAE) has been shown to improve the extraction efficiency of bioactive compounds while reducing processing time and costs. MEAE using tannase alone (MEAE-Tan), or in combination with cellulase and pectinase (MEAE-Tan-Cel-Pec), was optimized to produce enriched phenolic and antioxidant extracts from olive pomace. The individual and integrated impact of enzyme concentration, temperature, and pomace/water ratio were determined using a central composite rotatable design. Optimal extraction conditions for MEAE-Tan (60 °C, 15 min, 2.34% of enzyme (w/w), and 1:15 pomace/water ratio) and MEAE-Tan-Cel-Pec (46 °C, 15 min, 2% of enzymes (w/w), in the proportion of 1:1:1, and 1:20 pomace/water ratio) resulted in extracts containing 7110.6 and 2938.25 mg GAE/kg, respectively. The antioxidant activity of the extracts was correlated with phenolic acid release, which was enzyme-dependent, as determined with HPLC-DAD analysis. Enzyme selection had a significant impact on the phenolic profile of extracts, with tannase releasing high concentrations of chlorogenic acid and the combined use of enzymes releasing high concentrations of hydroxytyrosol and chlorogenic and ferulic acids. The novelty of this study relies on the integration and optimization of two green technologies (microwave- and enzyme-assisted extraction) to improve the extraction efficiency of bioactive phenolics from olive pomace while reducing processing time and costs. While these techniques have been evaluated isolated, the benefits of using both processing strategies simultaneously remain largely unexplored. This study demonstrates the effectiveness of the integration and processing optimization of two environmentally friendly technologies as a promising alternative to treat agro-industrial byproducts.

Dose-Dependency of the Glycemic Response to Polyphenol-Rich Sugarcane Extract (PRSE)

Foods high in available carbohydrates, such as plain white sugar or sucrose, increase the postprandial blood glucose levels that may aggravate the risk of developing Type 2 Diabetes. One class of compounds that is gaining popularity due to its potential application in reducing the release of sugars for absorption into the body is polyphenols. The study aimed to investigate the effect of adding different doses of polyphenol-rich sugarcane extract (PRSE) to sucrose to lower the postprandial glycemia of the participants in a non-randomized study. The four test samples’ Glycemic Index (GI) values were calculated based on the standardized recommended methodology by comparing the area under the curve (AUC) of the test samples against the glucose standard. The glucose concentration curves were similar for the four test foods. The glucose response curves, and GI values were decreased in a dose-dependent manner. The results of this study indicate that PRSE-coated sugar can lower postprandial glycemia in normal individuals. Additionally, decreasing GI values with an increasing concentration of polyphenols suggests a dose-dependent effect between polyphenol levels and GI.

Effects of sodium nitrite reduction, removal or replacement on cured and cooked meat for microbiological growth, food safety, colon ecosystem, and colorectal carcinogenesis in Fischer 344 rats

Epidemiological and experimental evidence indicated that processed meat consumption is associated with colorectal cancer risks. Several studies suggest the involvement of nitrite or nitrate additives via N-nitroso-compound formation (NOCs). Compared to the reference level (120 mg/kg of ham), sodium nitrite removal and reduction (90 mg/kg) similarly decreased preneoplastic lesions in F344 rats, but only reduction had an inhibitory effect on Listeria monocytogenes growth comparable to that obtained using the reference nitrite level and an effective lipid peroxidation control. Among the three nitrite salt alternatives tested, none of them led to a significant gain when compared to the reference level: vegetable stock, due to nitrate presence, was very similar to this reference nitrite level, yeast extract induced a strong luminal peroxidation and no decrease in preneoplastic lesions in rats despite the absence of NOCs, and polyphenol rich extract induced the clearest downward trend on preneoplastic lesions in rats but the concomitant presence of nitrosyl iron in feces. Except the vegetable stock, other alternatives were less efficient than sodium nitrite in reducing L. monocytogenes growth.

Effect of Cucumis melo L. peel extract supplemented postbiotics on reprograming gut microbiota and sarcopenia in hindlimb-immobilized mice

Postbiotics made from lactic acid bacteria may ameliorate sarcopenia via the metabolic reprogramming of gut dysbiosis. This study investigated the anti-sarcopenic effect of postbiotics (WDK) produced from polyphenol-rich melon peel extract (Cucumis melo L. var. makuwa, KEE) and whey with Lentilactobacillus kefiri DH5 (DH5) in C2C12 skeletal muscle cells and hindlimb-immobilized mice. WDK significantly ameliorated palmitate-induced atrophy of C2C12 cells, restoring myotube length and diameter. It also upregulated the expression of myogenic genes including Atrogin-1, Igf-1, and MyoD. Hindlimb-immobilized C57BL/6J mice were randomly divided and orally administered 10 mL/kg body weight of saline (CON), Whey, Whey + DH5 (WD), DH5 + KEE, Whey + DH5 + KEE postbiotic (WDK) for three weeks (n = 10/group). Interestingly, WDK significantly improved muscle function in hindlimb-immobilized mice by restoring both the grip strength and the mass of the soleus muscle, which was closely related to the upregulation of the myoD gene. WDK increased microbial diversity and modulated the distribution of intestinal bacteria, particularly those involved in protein synthesis and the production of butyrate. There was a significant correlation between myogenic biomarkers and butyrate producing gut microbiota. Restoration of muscle mass and function following postbiotic WDK is strongly related to the regulation of myogenic genes by in part remodulating gut microbiota. In conclusion, these findings suggest that polyphenol- and whey-based postbiotics WDK may have potential as an effective manner to combat the progression of sarcopenia.

The Antioxidant and Prebiotic Activities of Mixtures Honey/Biomimetic NaDES and Polyphenols Show Differences between Honeysuckle and Raspberry Extracts.

In our previous research, we demonstrated that honey and its biomimetic natural deep eutectic solvent (NaDES) modulate the antioxidant activity (AOA) of the raspberry extract (RE). In this study, we evaluated the AOA behaviour of the mixture honey/NaDES-honeysuckle (Lonicera caprifolium, LFL) extract and compared it with the mixture honey/NaDES-RE. These two extracts have similar major flavonoids and hydroxycinnamic acid compounds but differ in their total content and the presence of anthocyanins in RE. Therefore, it was of interest to see if the modulation of the LFL polyphenols by honey/NaDES was similar to that of RE. We also evaluated the prebiotic activity of these mixtures and individual components on Limosilactobacillus reuteri DSM 20016. Although honey/NaDES modulated the AOA of both extracts, from synergism to antagonism, the modulation was different between the two extracts for some AOA activities. Honey/NaDES mixtures enriched with LFL and RE did not show significant differences in bacterial growth stimulation. However, at a concentration of 45 mg/mL, the honey -LFL mixture exhibited a higher effect compared to the honey-RE mixture. The antioxidant and prebiotic properties of mixtures between honey and polyphenol-rich extracts are determined by multiple interactions in complex chemical systems.

Eremophila purpurascens: Anti-oxidant, Anti-hyperglycemic, and Hepatoprotective Potential of Its Polyphenolic Rich Leaf Extract and Its LC-ESI-MS/MS Chemical Characterization and Standardization.

The genus Eremophila, despite comprising more than 250 species, has scarce literature studies that could be traced concerning the chemical profile and bioactivity of Eremophila purpurascens. The current study targets the investigation of the in vitro and in vivo anti-oxidant, anti-hyperglycemic, and hepatoprotective potential of the polyphenol-rich leaf extract of E. purpurascens (EP). EP showed promising total anti-oxidant capacity with IC50 values of 106 and 114 μg/mL in 2,2'-azinobis [3-ethylbenzothiazoline-6-sulfonic acid]-diammonium salt (ABTS) and diphenyl-1-picrylhydrazyl (DPPH) assays, respectively, with total anti-oxidant capacities of 331, 245, and 1767 μmol/g in ABTS, DPPH, and ferric reducing anti-oxidant power assays, respectively. In HepG2 cells, pre-treated with CCl4, a dose of 100 μg/mL EP ameliorated the reduced superoxide dismutase and glutathione levels and total anti-oxidant capacity with values of 312.5 U/mL, 15.47 mg/dL, and 1.03 nmol/mL, respectively. In vitro anti-diabetic evaluation using 3T3-L1 adipocyte culture showed that at a dose of 30 μg/mL, the EP extract elicited a 6.3% decrease in the concentration of glucose (22.4 mmol/L), showing significant amelioration with regard to pioglitazone and insulin. EP also demonstrated elevated serum insulin by 77.78% with a marked reduction in fasting blood glucose level by 64.55% relative to the streptozotocin diabetic rats in vivo. EP also relieved the liver stress markers both in vitro in CCl4 and in vivo in tamoxifen (TAM) models. EP markedly decreased TAM toxicity, as demonstrated by the decline in the liver stress markers, ALT and AST, by 36.1 and 51.1%, respectively. It also relieved the oxidative stress triggered by TAM, as revealed by the reduction in the levels of TBARs and TNF-α by 21.4 and 40%, respectively. Liquid chromatography electrospray ionization mass spectrometry of EP revealed a total of twelve peaks belonging to phenylpropanoids, lignans, and phenolics, where verbascoside and pinoresinol-4-O-β-d-glucoside represented the most abundant secondary metabolites. The docking experiment showed that tri-O-galloyl-hexoside had the best fitting within the NADPH oxidase active sites with binding energy (ΔG = -81.12 kcal/mol). Thus, the plant can be of beneficial value in the control of hyperglycemia in diabetic patients, besides its prophylactic potential against hepatic complications.

Thyme (Thymus quinquecostatus Celak) Polyphenol-Rich Extract (TPE) Alleviates HFD-Induced Liver Injury in Mice by Inactivating the TLR4/NF-κB Signaling Pathway through the Gut-Liver Axis.

Non-alcoholic fatty liver disease (NAFLD) represents a significant and urgent global health concern. Thyme (Thymus quinquecostatus Celak) is a plant commonly used in cuisine and traditional medicine in Asian countries and possesses potential liver-protective properties. This study aimed to assess the hepatoprotective effects of thyme polyphenol-rich extract (TPE) on high-fat diet (HFD)-induced NAFLD and further explore possible mechanisms based on the gut-liver axis. HFD-induced liver injury in C57 mice is markedly ameliorated by TPE supplementation in a dose-dependent manner. TPE also regulates the expression of liver lipid metabolic genes (i.e., Hmgcr, Srebp-1, Fasn, and Cyp7a1), enhancing the production of SCFAs and regulating serum metabolites by modulating gut microbial dysbiosis. Furthermore, TPE enhances the intestinal barrier function and alleviates intestinal inflammation by upregulating tight junction protein expression (i.e., ZO-1 and occluding) and inactivating the intestinal TLR4/NF-κB pathway in HFD-fed mice. Consequently, gut-derived LPS translocation to the circulation was blocked, the liver TLR4/NF-κB signaling pathway was repressed, and subsequent pro-inflammatory cytokine production was restrained. Conclusively, TPE might exert anti-NAFLD effects through the gut-liver axis and has the potential to be used as a dietary supplement for the management of NAFLD.

Complexation of octenyl succinic anhydride-esterified corn starch/polyphenol-rich Roselle (Hibiscus sabdariffa L.) extract: Structural and digestibility features

Native and octenyl succinic anhydride (OSA; degree of substitution = 0.0164 ± 0.002)-esterified corn starches were employed for the manufacture of the starch-polyphenol V-type complexes. For this, the aqueous extract of Roselle was used as a rich source of polyphenols. Assembled OSA starch-polyphenol VI-type complexes were obtained, primarily due to hydrogen (H)-bond interactions and hydrophobic CH-π interactions between α-(1 → 4) glycosidic chains of the hydrophobic core of amylose helix, which is made up of aliphatic –CH2 groups, and the phenolic (flavonic) rings of the polyphenol-rich Roselle extract. This reduced the apparent amylose content, confirming amylose as the main macromolecule involved in the formation of starch VI-type complexes. The presence of the Roselle extract apparently increases the starch tendency to retrograde. Therefore, a retrograded starch (RS3) and assembled OSA starch-polyphenol VI-type complex (RS5) mixture could be obtained. This fact allowed the manufacture of starchy materials with resistant starch (RS) contents as high as ∼35% and low digestion rate. These findings are interesting for the development of products of potential application in the dietary management of metabolic syndrome, and leave new research questions to be addressed in the field of starch-polyphenol V-type complexes.