Gastroprotective Effects of Spirulina platensis, Golden Kiwifruit Flesh, and Golden Kiwifruit Peel Extracts Individually or in Combination against Indomethacin-Induced Gastric Ulcer in Rats.

This study was conducted to investigate the therapeutic effect of hydro-alcoholic extract of Spirulina platensis (SP), golden kiwifruit (Actinidia chinensis) flesh (KF), and golden kiwifruit peel (KP) individually or in combination (SFP) on indomethacin-induced gastric ulcer in rats. Negative control rats (GI) were orally administered distilled water in parallel with other treatments. The positive control rat group (GII) was administered 30 mg kg-1 indomethacin to induce gastric ulcers. The KF and KF extracts were used individually or together with SP in treating indomethacin-induced gastric ulcerated rat groups. Gastric ulcerated rat's groups GIII, GIV, GV, GVI, and GVII were orally administered at 30 mg kg-1 rat body weight as total phenolic content (TPC) equivalent from SP, KF, KP, SPF extracts, and Lansoprazole (30 mg kg-1, as reference drug) daily up to 14 days, respectively. The relevant biochemical parameters, antioxidant biomarkers, and histopathological examination were examined. Remarkably, treating rats with SP, KF, KP, and SFP extracts markedly reduced gastric juice and stomach volume expansion induced by indomethacin. The SP significantly retrieved the pH of gastric juice to a regular rate compared to GI. The ulcer index (UI) was significantly attenuated by SP, KF, KP, and SFP administration. The protection index percentage (PI %) was 80.79, 54.51, 66.08, 75.74, and 74.86% in GIII, GIV, GV, GVI, and GVII, respectively. The gastric mucin content was significantly better attenuated by 95.7 in GIII compared to its content in GI. Lansoprazole increased mucin content by 80.3%, which was considerably lower than SP and SFP. SP, KF, KP, SFP, and Lansoprazole improved the reform of gastric mucosal-increased secreted mucus by 95.6, 61.3, 64.8, 103.1, and 80.2% in GIII, GIV, GV, GVI, and GVII, respectively. Interestingly, SFP efficiently increased vit. B12 level by 46.0% compared to other treatments. While Lansoprazole administrating did not significantly attenuate vit. B12 level. The SP and SFP improved iron and Hemoglobin (HB) levels depending on treatment. SP, KF, KP, and SFP significantly decreased the malondialdehyde (MDA) and increased reduced glutathione (GSH) as well as superoxide dismutase (SOD) levels in blood and stomach tissues. The most potent effect was observed with SP, and SFP was even better than Lansoprazole. Histopathologically, treating rats with SP extract showed a marked reduction of gastric damage and severity changes induced by indomethacin. KP was much better than KF in lessening gastric histopathological damages caused by indomethacin. SFP significantly alleviates gastric histopathological alterations. The lansoprazole-treated group (GVII) greatly relieved the gastric histopathological changes and recorded mild focal necrosis and desquamation of the mucosa in addition to mild oedema in the serosal layer. In conclusion, the presented results proved the antiulcer potential of SP and A. chinensis extracts against an indomethacin-induced gastric ulcer in rats, which may be due to their antioxidant and anti-inflammation efficiency. Thus, these data suggested that SP, KF, KP, and SFP extracts as natural and safe alternatives have a gastroprotective potential against indomethacin-induced gastric ulceration. The antioxidative and anti-inflammatory properties are probable mechanisms.

Antioxidant activity and polyphenol content in extracts from various parts of fresh and frozen mangosteen.

BACKGROUND: The search for new sources of natural antioxidants is very important because many diseases are caused by oxidative stress. Fruit which contain antioxidants are an important part of a healthy diet. The aim of this study was to evaluate the antioxidant activity of extracts of both the fresh and frozen peel and the flesh of Garcinia mangostana L. METHODS: The extracts from the fresh and frozen peel and the flesh of mangosteen were prepared by ultrasound-assisted extraction using 20%, 40%, 70% and 96% (v/v) ethanol for 15, 30 or 60 minutes. The antioxidant potential was evaluated by the DPPH, ABTS, CUPRAC, FRAP and FIC methods, whereas the total phenolic content was measured using the Folin-Ciocalteu (F-C) technique. The contents of anthocyanins and flavonoids in the peel extracts were also determined. RESULTS: In most cases, the highest antioxidant activity was observed in the fresh peel samples. It was higher than the antioxidant potential of the frozen peels and the fresh and frozen flesh. The ultrasound-assisted extraction, in particular those lasting 30 or 60 minutes and using ethanol in concentrations higher than 20% (v/v), seemed to be an effective extraction process. CONCLUSIONS: The obtained results suggest that G. mangostana, in particular its peels, could be a valuable source of antioxidants. The extraction parameters, such as the time or solvent concentration, as well as the type of plant material, had an impact on the tested properties of the extracts. However, more detailed studies on the antioxidant activity of the studied plants are required.

Grape skins as supplements for color development in Pinot noir wine.

A particular challenge to making wine from Pinot noir grapes is the delicate flavor, light color and poor ageing potential of the wine. Conventional Pinot noir must preparations were compared with those made using a skin-based supplement to assess the impact on non-bleachable (sulfur resistant) pigments in the wine. When supplemented with either fresh grape pomace of Pinot noir, Pinot gris or Chardonnay grapes; Pinot noir grape marc or a commercial liquid grape skin extract, the additional seeds and pulp from the supplements were shown to compromise the development of stable pigments in the wine. To compare the relative merits of tannin derived from grape skins and seeds, the supplements used in a parallel experiment were the skins alone of the same three grape varieties and at six months bottle age, the stable pigment concentration was found to exceed the amount attributable to the supplement. A third experiment used fermented grape skins as the supplement, with 85% of the supplementary anthocyanin recovered as stable pigment complexes in the wine. Notably, this series of experiments showed that supplements containing grape seeds appeared to compromise non-bleachable pigment formation in the wine while skin only supplements stimulated their development.

Effects of peanut shell and skin extracts on the antioxidant ability, physical and structure properties of starch-chitosan active packaging films.

In this study, the antioxidant ability of peanut shell and skin extracts and their effects on the physical and structure properties of starch-chitosan film were investigated. The results showed that the DPPH radical scavenging ability of peanut skin extracts was significantly higher than the peanut shell extracts. This could be due to the rich rutin and 4-O-caffeoulquinic acid existed in the peanut skin extracts. When added the peanut skin and shell extracts into the starch-chitosan film, the apparent viscosity of film forming solution at 100 s-1 decreased. Moreover, water vapor permeability and swelling of film decreased with the addition of peanut skin and shell extracts. Two peanut extracts also increased the color L* and opacity of film. The tensile strength of film increased with the addition of peanut skin extracts, and decreased with peanut shell extracts. The addition of two extracts also resulted in the increase of endothermic temperature of starch-chitosan film. But there were no new peaks appeared in the FTIR image. Only the peaks at 3276 cm-1, 1382 cm-1, 1249 cm-1 shifted to 3273 cm-1, 1385 cm-1 and 1258 cm-1, which implied the peanut shell and skin extracts disturbed the hydrogen bond and vibration of molecular chain in film matrix.

Comparative analysis of the chemical composition and water permeability of the cuticular wax barrier in Welsh onion (Allium fistulosum L.).

Cuticular wax is a hydrophobic barrier between the plant surface and the environment that effectively reduces the loss of water. The surface of Welsh onion leaves is covered with wax. To explain the relationship between wax composition and water loss, we conducted this experiment. The water permeability and wax composition of leaves were determined by chemical and GC-MS methods. We performed a comparative analysis of the differences between the two cultivars and analyzed the relationship between water permeability and waxy components. Overall, the permeability to water was higher in 'Zhangqiu' than in 'Tenko'. The wax amount of 'Tenko' was 1.28-fold higher than that of 'Zhangqiu' and was primarily explained by the much larger amounts of ketones and alcohols in the former. Among the waxy components, C29 ketones were most abundant. There were substantial discrepancies in wax composition, total wax content, and water permeability between the two cultivars. The main reason for the discrepancy in water permeability may be the significantly lower aliphatic fraction in 'Zhangqiu' than in 'Tenko'. This study makes a vital contribution to drought resistance research on allium plants.

Apparent penetration depth in attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy of Allium cepa L. epidermis and cuticle.

Over the past decades, ATR-FTIR has emerged as promising tool for the identification of plants at the genus and (sub-) species level through surface measurements of intact leaves. Theoretical considerations regarding the penetration depth of the evanescent wave into the sample and the thickness of plant leaf cuticles suggest that the structure and composition of the cuticle represent universal taxonomic markers. However, experimental evidence for this hypothesis is scarce. In the current contribution, we present results of a series of simple experiments on epidermal monolayers derived from the bulbs of Allium cepa L. (Amaryllidaceae) as a model system to study the effect of an IR active probe located beyond the theoretical penetration depth of the evanescent wave. We found that this probe had a significant influence on the ATR-FTIR spectra for up to 4 epidermal layers stacked on top of each other corresponding to a total thickness of around 60 µm, exceeding the theoretical penetration depth of the evanescent wave by a factor of around 20. Altogether, our data indicate a major discrepancy between theory and practice in ATR-FTIR spectroscopy in general and provide strong evidence that in general plant leaf spectra cannot be fully explained by the structure and composition of the cuticle alone.

Anatomical, Phytochemical, and Histochemical Study of Juniperus rigida Needles at Different Altitudes.

Needles of Juniperus rigida are used in Chinese traditional medicine for the treatment of brucellosis, dropsy, skin disease, and rheumatoid arthritis. This is the first study that reports anatomical structures of the J. rigida needles collected at different altitudes. The most common anatomical, phytochemical, and histochemical techniques and methods are used. The results show that anatomical structures and chemical composition change significantly at different altitudes. The main anatomical characters are significant xeromorphic structures (thick epidermis, hypodermis, and cuticle), a stomatal band, a developed vascular bundle, and a marginal resin duct. The xeromorphic structures become more pronounced with increasing altitude. The phytochemical and histochemical results demonstrate that the content of the main chemical compounds (phenols and terpenoids) basically increases at a higher elevation. Histochemical analysis localizes the phenols in epidermal cells, sponge tissue, endothelial layer cells, and stomatal bands, and the terpenoids in palisade tissue, sponge tissue, and the edge of the resin duct. This work reveals the relation between anatomy and chemistry in J. rigida needles, contributes to the quality control of its ethno-medicine, and provides the evidence to develop the commercial cultivation.

Cellular Force Microscopy to Measure Mechanical Forces in Plant Cells.

Cellular force microscopy (CFM) is a noninvasive microindentation method used to measure plant cell stiffness in vivo. CFM is a scanning probe microscopy technique similar in operation to atomic force microscopy (AFM); however, the scale of movement and range of forces are much larger, making it suitable for stiffness measurements on turgid plant cells in whole organs. CFM experiments can be performed on living samples over extended time periods, facilitating the exploration of the dynamics of processes involving mechanics. Different sensor technologies can be used, along with a variety of probe shapes and sizes that can be tailored to specific applications. Measurements can be made for specific indentation depths, forces and timing, allowing for very precise mechanical stimulation of cells with known forces. High forces with sharp tips can also be used for mechanical ablation of cells with force feedback.

Achacha (Garcinia humilis) Rind Improves Cardiovascular Function in Rats with Diet-Induced Metabolic Syndrome.

Garcinia humilis is a fruit known as achachairú. It is native to South American countries such as Bolivia, Peru, and Brazil, but it is also cultivated as achacha in northern Australia. The aim of this study was to determine the phytochemicals in achacha rind and pulp and to investigate these components as potential treatments for the symptoms of metabolic syndrome. Both rind and pulp contain procyanidins and citric acid rather than hydroxycitric acid. Male Wistar rats (8⁻9 weeks old) were fed with either high-carbohydrate, high-fat, or corn starch diets for 16 weeks. Intervention groups were fed with either diet supplemented with 1.5% G. humilis rind powder or 2.0% G. humilis pulp for the last 8 weeks of the protocol. Rats fed a high-carbohydrate, high-fat diet exhibited hypertension, dyslipidemia, central obesity, impaired glucose tolerance, and non-alcoholic fatty liver disease. G. humilis rind decreased systolic blood pressure, diastolic stiffness, left ventricular inflammatory cell infiltration, and collagen deposition in high-carbohydrate, high-fat diet-fed rats. However, there was no change in glucose tolerance, body weight, or body composition. Therefore, G. humilis rind, usually a food by-product, but not the edible pulp, showed potential cardioprotection with minimal metabolic changes in a rat model of diet-induced metabolic syndrome.

Determination of phenolic compounds and antioxidant activities from peel, flesh, seed of guava (Psidium guajava L.).

White-flesh guava is widely planted in tropical or subtropical areas of Southeast Asia. Despite of folk statements on specific function, few researches are focused on the description of its plant secondary metabolites. In the present work, contents of total phenolics and flavonoids as well as antioxidant activity from different parts (peel, flesh, and seed) were determined. The constituents of ethanol extracts were characterized by HPLC-QTOF-MS. A total of 69 phenolic compounds as well as nine polar compounds were detected, with flavonoids, hydrolyzable tannins, phenolic acid derivatives, and benzophenones of the four predominant phenolic compounds. Moreover, the presence of other phenolics (lignan, phenylethanoid, stilbenoid, and dihydrochalcones) was revealed. Simultaneously, the polar compounds, such as triterpenoids, iridoid were identified. Benzophenones and triterpenoids were proved to be marked constitutes of peel and flesh, respectively. The existence of isoflavonoids, lignan, phenylethanoid were firstly reported for edible parts or by-products of guava. The results showed that white-flesh guavas, particularly peel parts, were superior resources of antioxidant compounds, with exploitation value.

Preclinical renal chemo-protective potential of Prunus amygdalus Batsch seed coat via alteration of multiple molecular pathways.

Prunus amygdalus Batsch (almond) is a classical nutritive traditional Indian medicine. Along with nutritive with anti-oxidant properties, it is, clinically, used in the treatment of various diseases with underlying anti-oxidant mechanism. This study is an effort to scrutinise the renal protective effect of P. amygdalus Batsch or green almond (GA) seed coat extract and its underlying mechanism in animal model of Ferric nitrilotriacetate (Fe-NTA) induced renal cell carcinoma (RCC). RCC was induced in Swiss Albino Wistar rats by intraperitoneal injection of Fe-NTA. The rats were then treated with ethanolic extract of GA (25, 50 and 100 mg/kg per oral) for 22 weeks. Efficacy of GA administration was evaluated by change in biochemical, renal, macroscopical and histopathological parameters and alterations. Additionally, interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and inflammatory mediator including prostaglandin E2 (PGE2), nuclear factor-kappa B (NF-κB) were also observed to explore the possible mechanisms. The oral administration of GA significantly (p < .001) altered the Fe-NTA induced RCC in rats by inhibition of renal nodules, decolourisation of tissues, tumour promoter marker including thymidine 3[H] incorporation, ornithine decarboxylase, renal parameters and anti-oxidant parameters in serum. Additionally, GA treatment significantly (p < .001) down-regulated the IL-6, IL-1ß, TNF-α, inflammatory mediators PGE2 and NF-κB in a dose-dependent manner. Histopathology observation supported the renal protective effect of GA by alteration in necrosis, size of Bowman capsules and inflammatory cells. Hence, it can be concluded that GA possesses observable chemo-protective action and effect on Fe-NTA induced RCC via dual inhibition mechanism one by inhibiting free radical generation and second by inhibiting inflammation.

Antioxidant and vasorelaxant activities induced by northeastern Brazilian fermented grape skins.

BACKGROUND: In northeastern Brazil, grape pomace has become a potential alternative byproduct because of the recover phenolic compounds from the vinification process. Comparative analyses were performed between lyophilized extract of grape skins from pomace, described as fermented (FGS), and fresh, unfermented (UGS) grape skins to show the relevant brand's composition upon the first maceration in winemaking. METHODS: The use of in vitro testing such as Folin-Ciocalteu's, DPPH free radical scavenger and HPLC methods were performed to evidence antioxidant effect and phenolic compounds. Additionally, vascular reactivity studies were performed in third-order branches of rat superior mesenteric arteries, which were obtained and placed in organ baths containing Krebs-Henseleit solution, maintained at 37 °C, gassed with a mixture of 95% O2 and 5% CO2, and maintained at pH 7.4. The in situ formation of reactive oxygen species (ROS) was evaluated in small mesenteric rings using oxidative fluorescent dihydroethidium dye. RESULTS: We found higher phenolic content and antioxidant activity in FGS when compared to UGS. HPLC analyses identified a significant number of phenolic compounds with antioxidant potential in both samples. The vasorelaxant effect induced by FGS was more potent than that induced by UGS, and the activity was attenuated after removal of vascular endothelium or by blockade of endothelium-derived relaxing factors, such as NO and EDHF. CONCLUSIONS: The FGS extract may be a great source of natural polyphenol products with potent antioxidant effects and endothelium-dependent vasodilatory actions involving NO and EDHF pathways.

Identification of Phenolic Compounds from Seed Coats of Differently Colored European Varieties of Pea (Pisum sativum L.) and Characterization of Their Antioxidant and In Vitro Anticancer Activities.

To date little has been done on identification of major phenolic compounds responsible for anticancer and antioxidant properties of pea (Pisum sativum L.) seed coat extracts. In the present study, phenolic profile of the seed coat extracts from 10 differently colored European varieties has been determined using ultrahigh-performance liquid chromatography-linear trap quadrupole orbitrap mass spectrometer technique. Extracts of dark colored varieties with high total phenolic content (up to 46.56 mg GAE/g) exhibited strong antioxidant activities (measured by 2,2-diphenyl-1-picrylhydrazyl or DPPH assay, and ferric ion reducing and ferrous ion chelating capacity assays) which could be attributed to presence of gallic acid, epigallocatechin, naringenin, and apigenin. The aqueous extracts of dark colored varieties exert concentration-dependent cytotoxic effects on all tested malignant cell lines (human colon adenocarcinoma LS174, human breast carcinoma MDA-MB-453, human lung carcinoma A594, and myelogenous leukemia K562). Correlation analysis revealed that intensities of cytotoxic activity of the extracts strongly correlated with contents of epigallocatechin and luteolin. Cell cycle analysis on LS174 cells in the presence of caspase-3 inhibitor points out that extracts may activate other cell death modalities besides caspase-3-dependent apoptosis. The study provides evidence that seed coat extracts of dark colored pea varieties might be used as potential cancer-chemopreventive and complementary agents in cancer therapy.

Influence of berry ripeness on accumulation, composition and extractability of skin and seed flavonoids in cv. Sangiovese (Vitis vinifera L.).

BACKGROUND: The anthocyanin and tannin concentration and composition of Vitis vinifera L. cv. Sangiovese berries were investigated from post-veraison to harvest. Exhaustive extraction with methanol and acetone was performed to determine the total flavonoid concentration, while a model hydroalcoholic solution was used to prepare extracts representing the winemaking process. The aim of this study was to improve the knowledge of the phenolic maturity of Sangiovese grape. RESULTS: The total anthocyanin concentration increased during ripening, but the quantity of extractable anthocyanins increased more rapidly than the total. The total skin tannin concentration declined from post-veraison to harvest, whereas the extractable portion increased, with little difference in the composition of the fractions. Both the total and extractable seed tannin concentration diminished rapidly just after veraison, and only small fluctuations were detected until harvest. CONCLUSION: These results indicate that the extractability of anthocyanins and skin tannins increases during ripening, whereas there is no clear trend for seed tannins during the same period. This is the first survey to study the behavior of phenolic compounds during different steps of ripening of Sangiovese grape. © 2016 Society of Chemical Industry.

Rheology and microstructure of binary mixed gel of rice bran protein-whey: effect of heating rate and whey addition.

BACKGROUND: Rice bran protein (RBP) is a valuable plant protein which has unique nutritional and hypoallergenic properties. Whey proteins have wide applications in the food industry, such as in dairy, meat and bakery products. RESULTS: Whey protein concentrate (WPC), RBP and their mixtures at different ratios (1:1, 1:2, 1:5 and 1:10 w/w) were heated from 20 to 90 °C at different heating rates (0.5, 1, 5 and 10 °C min(-1) ). The storage modulus (G') and gelling point (Tgel ) of WPC were higher than those of RBP, indicating the good ability of WPC to develop stiffer networks. By increasing the proportion of WPC in mixed systems, G' was increased and Tgel was reduced. Nevertheless, the elasticity of all binary mixtures was lower than that of WPC alone. Tgel and the final G' of RBP-WPC blends were increased by raising the heating rate. The RBP-WPC mixtures developed more elastic gels than RBP alone at different heating rates. RBP had a fibrillar and lentil-like structure whose fibril assembly had smaller structures than those of WPC. CONCLUSION: The gelling structure of the mixed gel of WPC-RBP was improved by adding WPC. Indeed, by adding WPC, gels tended to show syneresis and had lower water-holding capacity. Furthermore, the gel structure was produced by adding WPC to the non-gelling RBP, which is compatible with whey and can be applied as a functional food for infants and/or adults. © 2015 Society of Chemical Industry.

Effect of Processed Onions on the Plasma Concentration of Quercetin in Rats and Humans.

UNLABELLED: Onion is a major dietary source of the bioactive flavonoid, quercetin. Quercetin aglycone (QA) is exclusively distributed in the onion peel, although quercetin-4'-ß-O-glucoside (Q4'G) is present in both the peel and the bulb, and quercetin-3,4'-ß-O-diglucoside (Q3,4'diG) is present only the bulb. The bioavailability of flavonoids from fruits and vegetables is frequently affected by the manufacturing process and related conditions. The present study aimed to estimate the effect of food processing on the bioavailability of onion QA and its glucosides, Q4'G and Q3,4'diG, provided through the consumption of onion products. Rats were fed onion peel and onion bulb products-mixed meal or pure QA/Q4'G+Q3,4'diG-mixed meal at 5 mg QA equivalent/kg body weight. A comparison of the blood plasma concentrations strongly suggested that quercetin glucosides (Q4'G and Q3,4'diG) are superior or at least equal to QA in their bioavailability, when each purified compound is mixed with the meal. The intake of a peel powder-containing meal provided a significantly higher increase of plasma quercetin concentration than the peel extract, bulb powder, bulb extract, and bulb sauté containing meals at each period tested. A human ingestion study confirmed the superiority of onion peel powder to onion peel extract. The difference of log P for QA between peel powder and peel extract indicated that a food matrix improves the bioavailability of QA in onion peel products. These results demonstrated that the bioavailability of quercetin provided by not the onion bulb but the onion peel is significantly affected by food processing. PRACTICAL APPLICATION: Onion is a popular source of antioxidative flavonoid quercetin and its vascular function attracts considerable attention in relation to anti-atherosclerotic effect. The present study estimated the effect of food processing on the bioavailability of onion quercetin aglycone and its glucosides provided through the consumption of onion products. The intake of a peel powder-containing meal showed a significantly higher bioavailability than the peel extract, bulb powder, bulb extract, and bulb sauté containing meals. Hence, food processing of onion peel may enhance the health impact of onion quercetin by elevating its bioavailability.

Protective role of extracts of grape skin and grape flesh on ethanol-induced oxidative stress, inflammation and histological alterations in rat brain.

Ethanol consumption has deleterious effects on all organs and especially on brain. In our study, the radical scavenging properties of grape skin and grape flesh (contains natural antioxidants like polyphenols) was determined in vitro and for in vivo studies, male Wistar rats (16-18 week-old) and 100-120 gm weight were divided in five groups of six animals each. One group were fed with ethanol (1.6 gm/kg body weight), while second group were fed with ethanol (1.6 g/kg body weight) and grape skin extract (2.5 g/kg body weight), the third group were fed with ethanol (1.6 g/kg body weight) and grape flesh extract, daily once for 12 weeks, while the fourth group were fed with ethanol (1.6 g/kg body weight) and tocopheryl acetate (80 mg/kg/day) daily once for 12 weeks. Results of in vitro studies indicate that grape skin extracts showed significant radical scavenging properties (ROS). There was also significantly alteration of serum cytokines in our study.

Marigold flower-powder exhibits significant potential to inhibit lipid oxidation in rice bran tea.

We supplemented marigold flower-powder (MFP) in rice bran tea at different proportions as a source of natural antioxidant compounds. Changes of phenolic compounds, antioxidant activity, fatty acid composition and lipid oxidation in the rice bran tea with MFP after 30 days of storage were investigated, comparing results with the initial data. Adding MFP in rice bran tea resulted in an increased content and composition of phenolics and flavonoids along with enhanced antioxidant activities, which were increased in a dose-dependent manner. As a result, MFP supplementation of rice bran tea was able to retard the lipid oxidation as determined by the peroxide value (PV), due to the protection of essential fatty acids during 30 days of storage. The PVs were strongly negatively correlated (p < 0.01) with phenolic compounds, total phenolic content (TPC) and total flavonoid content (TFC), but were positively correlated with tocopherols and γ-oryzanol contents. We also found that the PV was positively correlated with the PUFA (poly unsaturated fatty acid) content but adverse results were found for SFA (saturated fatty acid) and MUFA (mono unsaturated fatty acid) contents. These findings suggest that MFP could be used as a natural antioxidant in foods for preventing lipid oxidation as well as extending the shelf-life of food products.

Tannin-rich pomegranate rind extracts reduce adhesion to and invasion of Caco-2 Cells by Listeria monocytogenes and decrease its expression of virulence genes.

Pomegranate rind is rich in tannins that have remarkable antimicrobial activities. This study aimed to evaluate the effects of a tannin-rich fraction from pomegranate rind (TFPR) on Listeria monocytogenes virulence gene expression and on the pathogen's interaction with human epithelial cells. Growth curves were monitored to determine the effect of TFPR on L. monocytogenes growth. The 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide and fluorescence staining assays were used to examine the cytotoxicity of TFPR. The effects of TFPR on L. monocytogenes adhesion to and invasion of epithelial cells were investigated using Caco-2 cells. Real-time quantitative PCR analysis was conducted to quantify mRNA levels of three virulence genes in L. monocytogenes. Results showed that a MIC of TFPR against L. monocytogenes was 5 mg/ml in this study. TFPR exhibited cytotoxicity against Caco-2 cells when the concentration was 2.5 mg/ml. Subinhibitory concentrations of TFPR significantly reduced, in a dose-dependent manner, adhesion to and invasion of Caco-2 cells by L. monocytogenes. When L. monocytogenes was grown in the presence of 2.5 mg/ml TFPR, the transcriptional levels of prfA, inlA, and hly decreased by 17-, 34-, and 28-fold, respectively.