Showing papers on "Ellagic acid published in 2017"

Anti-inflammatory potential of ellagic acid, gallic acid and punicalagin A&B isolated from Punica granatum

Abstract: Punica granatum (pomegranate), an edible fruit originating in the Middle East, has been used as a traditional medicine for treatment of pain and inflammatory conditions such as peptic ulcer. The numerous risks associated with nonsteroidal anti-inflammatory drugs (NSAIDs) for treatment of pain and inflammation give rise to using medicinal herbs as alternative therapies. This study aimed to evaluate the anti-inflammatory effect of isolated compounds from the ethyl acetate (EtOAc) fraction of P. granatum by determination of their inhibitory effects on lipopolysaccharide (LPS), stimulated nitric oxide (NO), prostaglandin E2 (PGE-2), interleukin-6 (IL-6) and cyclooxxgenase-2 (COX-2) release from RAW264.7 cells. The compounds ellagic acid, gallic acid and punicalagin A&B were isolated from EtOAc by high performance liquid chromatography (HPLC) and further identified by mass spectrometry (MS). The inhibitory effect of ellagic acid, gallic acid and punicalagin A&B were evaluated on the production of LPS-induced NO by Griess reagent, PGE-2 and IL-6 by immunoassay kit and prostaglandin E2 competitive ELISA kit, and COX-2 by Western blotting. Ellagic acid, gallic acid and punicalagin A&B potentially inhibited LPS-induced NO, PGE-2 and IL-6 production. The results indicate that ellagic acid, gallic acid and punicalagin may be the compounds responsible for the anti-inflammatory potential of P. granatum.

Isolation of Human Intestinal Bacteria Capable of Producing the Bioactive Metabolite Isourolithin A from Ellagic Acid

Abstract: Urolithins are intestinal microbial metabolites produced from ellagitannin- and ellagic acid-containing foods such as walnuts, strawberries, and pomegranates. These metabolites, better absorbed than their precursors, can contribute significantly to the beneficial properties attributed to the polyphenols ellagitannins and ellagic acid (EA). However, both the ability of producing the final metabolites in this catabolism (urolithins A, B and isourolithin A) and the health benefits associated with ellagitannin consumption differ considerably among individuals depending on their gut microbiota composition. Three human urolithin metabotypes have been previously described, i.e., metabotype 0 (urolithin non-producers), metabotype A (production of urolithin A as unique final urolithin) and metabotype B (urolithin B and/or isourolithin A are produced besides urolithin A). Although production of some intermediary urolithins has been recently attributed to intestinal species from Eggerthellaceae family named Gordonibacter urolithinfaciens and Gordonibacter pamelaeae, the identification of the microorganisms responsible for the complete transformation of EA into the final urolithins, especially those related to metabotype B, are still unknown. In the present research we illustrate the isolation of urolithin-producing strains from human feces of a healthy adult and their ability to transform EA into different urolithin metabolites, including isourolithin A. The isolates belong to a new genus from Eggerthellaceae family. EA transformation and urolithin production arisen during the stationary phase of the growth of the bacteria under anaerobic conditions. The HPLC-DAD-MS analyses demonstrated the sequential appearance of 3,8,9,10-tetrahydroxy-urolithin (urolithin M6), 3,8,9-trihydroxy-urolithin (urolithin C) and 3,9-dihydroxy-urolithin (isourolithin A) while 3,8-dihydroxy-urolithin (urolithin A) and 3-hydroxy-urolithin (urolithin B) were not detected. For the first time isourolithin A production capacity of pure strains has been described. The biological activity attributed to urolithins A and B and isourolithin A (anti-inflammatory, anti-carcinogenic, cardioprotective and neuroprotective properties) explains the relevance of identifying these urolithin-producing bacteria as potential novel probiotics with applications in the development of functional foods and nutraceuticals. Their human administration could improve the health benefits upon ellagitannin consumption, especially in metabotype 0 individuals. However, further research is necessary to probe well established beneficial effects on the host and safety requirements before being considered among the next-generation probiotics.

Neuroprotective Effects of Bioavailable Polyphenol-Derived Metabolites against Oxidative Stress-Induced Cytotoxicity in Human Neuroblastoma SH-SY5Y Cells

Abstract: Oxidative stress is involved in cell death in neurodegenerative diseases. Dietary polyphenols can exert health benefits, but their direct effects on neuronal cells are debatable because most phenolics are metabolized and do not reach the brain as they occur in the dietary sources. Herein, we evaluate the effects of a panel of bioavailable polyphenols and derived metabolites at physiologically relevant conditions against H2O2-induced apoptosis in human neuroblastoma SH-SY5Y cells. Among the 19 metabolites tested, 3,4-dihydroxyphenylpropionic acid, 3,4-dihydroxyphenylacetic acid, gallic acid, ellagic acid, and urolithins prevented neuronal apoptosis via attenuation of ROS levels, increased REDOX activity, and decreased oxidative stress-induced apoptosis by preventing the caspase-3 activation via the mitochondrial apoptotic pathway in SH-SY5Y cells. This suggests that dietary sources containing the polyphenol precursors of these molecules such as cocoa, berries, walnuts, and tea could be potential functional...

Antimicrobial activity of pomegranate peel extracts as affected by cultivar.

Abstract: Some studies have reported that different parts of the pomegranate fruit, especially the peel, may act as potential antimicrobial agents and thus might be proposed as a safe natural alternative to synthetic antimicrobial agents The high tannin content, especially punicalagin, found in pomegranate extracts, has been reported as the main compound responsible for such antimicrobial activity Because the pomegranate peel chemical composition may vary with the type of cultivar (sweet, sour-sweet and sour), pomegranates may also differ with respect to their antimicrobial capacity; Results: The extract from PTO8 pomegranate cultivar peel had the highest antimicrobial activity, as well as the highest punicalagins (α and β) and ellagic acid concentrations In the results obtained from both antibacterial and antifungal activity studies, the sour-sweet pomegranate cultivar PTO8 showed the best antimicrobial activity, and the highest ellagic acid concentrations; Conclusion: The results of the present study suggest that ellagic acid content has a significant influence on the antimicrobial activity of the pomegranate extracts investigated The pomegranate peel of the PTO8 cultivar is a good source of antifungal and antibacterial compounds, and may represent an alternative to antimicrobial agents of synthetic origin © 2016 Society of Chemical Industry; © 2016 Society of Chemical Industry

Ellagic acid in Emblica officinalis exerts anti-diabetic activity through the action on β-cells of pancreas

Abstract: The present study was undertaken to explore the possible anti-diabetic mechanism(s) of Emblica officinalis (EO) and its active constituent, ellagic acid (EA), in vitro and in vivo. Neonatal streptozotocin-induced non-obese type 2 diabetic rats were treated with a methanolic extract of EO (250 or 500 mg/kg) for 28 days, and blood glucose, serum insulin, and plasma antioxidant status were measured. Insulin and glucagon immunostaining and morphometry were performed in pancreatic section, and liver TBARS and GSH levels were measured. Additionally, EA was tested for glucose-stimulated insulin secretion and glucose tolerance test. Treatment with EO extract resulted in a significant decrease in the fasting blood glucose in a dose- and time-dependent manner in the diabetic rats. It significantly increased serum insulin in the diabetic rats in a dose-dependent manner. Insulin-to-glucose ratio was also increased by EO treatment. Immunostaining of pancreas showed that EO250 increased β-cell size, but EO500 increased β-cells number in diabetic rats. EO significantly increased plasma total antioxidants and liver GSH and decreased liver TBARS. EA stimulated glucose-stimulated insulin secretion from isolated islets and decreased glucose intolerance in diabetic rats. Ellagic acid in EO exerts anti-diabetic activity through the action on β-cells of pancreas that stimulates insulin secretion and decreases glucose intolerance.

Health benefits of walnut polyphenols: An exploration beyond their lipid profile

Abstract: Walnuts are commonly found in our diet and have been recognized for their nutritious properties for a long time. Traditionally, walnuts have been known for their lipid profile, which has been linked to a wide array of biological properties and health-promoting effects. In addition to essential fatty acids, walnuts contain a variety of other bioactive compounds, such as vitamin E and polyphenols. Among common foods and beverages, walnuts represent one of the most important sources of polyphenols, hence their effect over human health warrants attention. The main polyphenol in walnuts is pedunculagin, an ellagitannin. After consumption, ellagitannins are hydrolyzed to release ellagic acid, which is converted by gut microflora to urolithin A and other derivatives such as urolithins B, C, and D. Ellagitannins possess well known antioxidant and anti-inflammatory bioactivity, and several studies have assessed the potential role of ellagitannins against disease initiation and progression, including cancer, cardiovascular, and neurodegenerative diseases. The purpose of this review is to summarize current available information relating to the potential effect of walnut polyphenols in health maintenance and disease prevention.

Main components of pomegranate, ellagic acid and luteolin, inhibit metastasis of ovarian cancer by down-regulating MMP2 and MMP9.

Abstract: Ovarian cancer is the third most common cancer in the female reproductive organs and epithelial ovarian cancer has the highest lethality of all gynecological cancers. Pomegranate fruit juice (PFJ) has been shown to inhibit the growth of several types of cancer other than ovarian cancer. In this study, we exposed the ovarian cancer cell line A2780 to PFJ and two of its components (ellagic acid and luteolin). MTT and wound healing assays demonstrated that all three treatments suppressed the proliferation and migration of the ovarian cancer cells. In addition, western blotting and ELISA assays showed that the expression levels of MMP2 and MMP9 gradually decreased after treatment with increasing concentrations of ellagic acid and luteolin. To confirm our findings in the in vitro experiments, we used another ovarian cancer cell line, ES-2, in nude mice experiments. All three treatments inhibited tumor growth without obvious side-effects. Furthermore, compared with the control group, the expression levels of MMP2 and MMP9 were depressed. Ellagic acid induced a greater effect than luteolin, suggesting that ellagic acid might be a promising candidate for further preclinical testing for treatment of human ovarian cancer.

In vitro gastrointestinal digestion promotes the protective effect of blackberry extract against acrylamide-induced oxidative stress

Abstract: Acrylamide (AA)-induced toxicity has been associated with accumulation of excessive reactive oxygen species. The present study was therefore undertaken to investigate the protective effect of blackberry digests produced after (BBD) in vitro gastrointestinal (GI) digestion against AA-induced oxidative damage. The results indicated that the BBD (0.5 mg/mL) pretreatment significantly suppressed AA-induced intracellular ROS generation (56.6 ± 2.9% of AA treatment), mitochondrial membrane potential (MMP) decrease (297 ± 18% of AA treatment) and glutathione (GSH) depletion (307 ± 23% of AA treatment), thereby ameliorating cytotoxicity. Furthermore, LC/MS/MS analysis identified eight phenolic compounds with high contents in BBD, including ellagic acid, ellagic acid pentoside, ellagic acid glucuronoside, methyl-ellagic acid pentoside, methyl-ellagic acid glucuronoside, cyanidin glucoside, gallic acid and galloyl esters, as primary active compounds responsible for antioxidant action. Collectively, our study uncovered that the protective effect of blackberry was reserved after gastrointestinal digestion in combating exogenous pollutant-induced oxidative stress.

Antiproliferative activity of the ellagic acid-derived gut microbiota isourolithin A and comparison with its urolithin A isomer: the role of cell metabolism

Abstract: Urolithins, metabolites produced by the gut microbiota from ellagic acid, have been acknowledged with cancer chemopreventive activity. Although urolithin A (Uro-A) has been reported to be the most active one, 10–50 % of humans can also produce the isomer isourolithin A (IsoUro-A). However, no biological activity for IsoUro-A has been reported so far. Herein, we describe for the first time the antiproliferative effect of IsoUro-A, compared to Uro-A, against both human colon cancer (Caco-2) and normal (CCD18-Co) cell lines. Cell proliferation was evaluated by MTT and Trypan blue exclusion assays. Cell cycle was analyzed by flow cytometry and apoptosis measured by the Annexin V/PI method. Finally, urolithins metabolism was analyzed by HPLC–DAD-MS/MS. IsoUro-A inhibited the proliferation of Caco-2 cells in a time- and dose-dependent manner, though it was significantly lower than Uro-A (IC50 = 69.7 ± 4.5 and 49.2 ± 3.8 μM at 48 h, respectively). Both urolithins arrested Caco-2 cell cycle at S and G2/M phases and induced apoptosis at concentrations previously found in human colon tissues. Notably, Caco-2 cells glucuronidated more efficiently IsoUro-A than Uro-A (~50 vs. ~20 % of conversion after 48 h, respectively). Both Uro-A and IsoUro-A glucuronides did not exert antiproliferative effects. In addition, cell growth inhibition was higher in Caco-2 than in normal cells. IsoUro-A exerts strong antiproliferative activity, which is reduced by the extensive glucuronidation at 9-position in cancer cells. Further studies are needed to elucidate whether the in vitro structure–activity relationship found for Uro-A and IsoUro-A plays any role in humans.

Phenolic Compositions and Antioxidant Properties in Bark, Flower, Inner Skin, Kernel and Leaf Extracts of Castanea crenata Sieb. et Zucc

Abstract: In this study, different plant parts (barks, flowers, inner skins, kernels and leaves) of Castanea crenata (Japanese chestnut) were analyzed for total phenolic, flavonoid, and tannin contents. Antioxidant properties were evaluated by using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), reducing power, and β-carotene bleaching methods. The highest total phenolic and tannin contents were found in the inner skins (1034 ± 7.21 mg gallic acid equivalent/g extract and 253.89 ± 5.59 mg catechin equivalent/g extract, respectively). The maximum total flavonoid content was observed in the flowers (147.41 ± 1.61 mg rutin equivalent/g extract). The inner skins showed the strongest antioxidant activities in all evaluated assays. Thirteen phenolic acids and eight flavonoids were detected and quantified for the first time. Major phenolic acids were gallic, ellagic, sinapic, and p-coumaric acids, while the principal flavonoids were myricetin and isoquercitrin. The inner skin extract was further fractionated by column chromatography to yield four fractions, of which fraction F3 exhibited the most remarkable DPPH scavenging capacity. These results suggest that C. crenata provides promising antioxidant capacities, and is a potential natural preservative agent in food and pharmaceutical industries.

Preharvest Ultraviolet C Irradiation Increased the Level of Polyphenol Accumulation and Flavonoid Pathway Gene Expression in Strawberry Fruit

Abstract: Preharvest ultraviolet C (UV-C) irradiation is an innovative approach for increasing the bioactive phytochemical content of strawberries to increase the disease resistance and nutritional value. This study investigated the changes in individual flavonoids in strawberry developed with three different cumulative doses of preharvest UV-C treatment (low, 9.6 kJ m–2; middle, 15 kJ m–2; and high , 29.4 kJ m–2). Significant accumulation (p < 0.05) of phenolics (25–75% increase), namely, cyanidin 3-glucoside, pelargonidin 3-glucoside/rutinoside, glucoside and glucuronide of quercetin and kaempferol, and ellagic acid, was found in the fruit subjected to low and middle supplemental doses of UV-C radiation. The expression of the flavonoid pathway structural genes, i.e., FaCHS1, FaCHI, FaFHT, FaDFR, FaFLS, and FaFGT, was upregulated in the low- and middle-dose groups, while the early stage genes were not affected by the high dose. FaMYB1 was also relatively enhanced in the low- and middle-dose groups, while FaASR was...

Antioxidants of Phyllanthus emblica L. Bark Extract Provide Hepatoprotection against Ethanol-Induced Hepatic Damage: A Comparison with Silymarin.

Abstract: Phyllanthus emblica L. (amla) has been used in Ayurveda as a potent rasayan for treatment of hepatic disorders. Most of the pharmacological studies, however, are largely focused on PE fruit, while the rest of the parts of PE, particularly, bark, remain underinvestigated. Therefore, we aimed to investigate the protective effect of the hydroalcoholic extract of Phyllanthus emblica bark (PEE) in ethanol-induced hepatotoxicity model in rats. Total phenolic, flavonoid, and tannin content and in vitro antioxidant activities were determined by using H2O2 scavenging and ABTS decolorization assays. Our results showed that PEE was rich in total phenols (99.523 ± 1.91 mg GAE/g), total flavonoids (389.33 ± 1.25 mg quercetin hydrate/g), and total tannins (310 ± 0.21 mg catechin/g), which clearly support its strong antioxidant potential. HPTLC-based quantitative analysis revealed the presence of the potent antioxidants gallic acid (25.05 mg/g) and ellagic acid (13.31 mg/g). Moreover, one-month PEE treatment (500 and 1000 mg/kg, p.o.) followed by 30-day 70% ethanol (10 mL/kg) administration showed hepatoprotection as evidenced by significant restoration of ALT (p < 0.01), AST (p < 0.001), ALP (p < 0.05), and TP (p < 0.001) and further confirmed by liver histopathology. PEE-mediated hepatoprotection could be due to its free radical scavenging and antioxidant activity that may be ascribed to its antioxidant components, namely, ellagic acid and gallic acid. Thus, the results of the present study support the therapeutic claims made in Ayurveda about Phyllanthus emblica.

Functional tea from a Brazilian berry: Overview of the bioactives compounds

Abstract: The consumption of berries has become a trend with confirmed health properties; however, fruit peels have been wasted despite their high concentrations of bioactive compounds. Tea made from jaboticaba (Myrciaria jaboticaba) peel (JP) could be an alternative to make use of this byproduct and contribute to increased intake of polyphenols. For this reason, this study investigated the JP chemical composition and bioactive profile, as well as the antioxidant capacity of its aqueous extract (JPT – 25 g L−1). The peel corresponded to approximately 35% of fruit weight. Total fiber content was approximately 30 g 100 g−1, and the soluble portion represented 8.50 ± 0.21 g 100 g−1. JPT showed strong antioxidant capacity according to all methods tested (FRAP, DPPH, and ORAC). Phenolic, flavonoid, and anthocyanin content were 54.55 mg GAE, 8.33 mg catechin, and 4.34 mg cyanidin 3-glucoside in 100 mL, respectively. Phenolic content in a cup of JPT (250 mL) was approximately 150 mg GAE, which could be considered an important source of bioactives. Cyanidin-3-O-glucoside, delphinidin-3-O-glucoside, and ellagic acid were identified in JPT by LC-DAD-ESI/MS. Other polyphenols were investigated by HPLC-DAD-FLD in the hydrolyzed extract, and gallic acid and rutin were the prevalent compounds after cyanidin-3-O-glucoside. The hydrolysis increased total phenolic, but not affected the antioxidant capacity according to DPPH e FRAP. The JPT color, anthocyanins and antioxidant capacity showed stability in refrigerated conditions, even without additives, for up to three days. These findings suggest that aqueous extract could be an adequate way to utilize the functional properties of jaboticaba peel.

Identification of nonvolatile compounds in clove (Syzygium aromaticum) from Manado

Abstract: Syzygium aromaticum (clove) are native to Indonesia and have been widely used in food industry due to their flavor. Nonvolatile compounds contribute to flavor, mainly in their taste. Currently, there is very little information available about nonvolatile compounds in clove. Identification of nonvolatile compounds is important to improve clove’s value. Compound extraction was conducted by maceration in ethanol. Fractionations of the extract were performed by using gravity column chromatography on silica gel and Sephadex LH-20 as stationary phase. Nonvolatile compounds were identified by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS). LC-MS/MS was operated in negative mode with 0.1 % formic acid in water and acetonitrile as mobile phase. Nonvolatile compounds were identified by fragment analysis and compared to references. Several compounds had been identified and characterized asquinic acid, monogalloylglucose, gallic acid, digalloylglucose, isobiflorin, biflorin, ellagic acid, hydroxygallic acid, luteolin, quercetin, naringenin, kaempferol, isorhamnetin, dimethoxyluteolin, and rhamnetin. These compounds had two main flavor perceptions, i.e. astringent, and bitter.