Synthesis, characterization and protection effect of black rice anthocyanins nano-composite against hepatotoxicity induced by methotrexate in rats

Abstract The present study aimed to investigate the beneficial of prepared black rice anthocyanins nano-composite (An-AgNps) against hepatotoxicity induced by methotrexate (MTX) in rats. Anthocyanins nano-composite was prepared by silver as the metallic ion reduction and were characterized by IR and SEM. The rats in our experiment were divided into five groups. Serum lipid profile, serum transaminases (ALT and AST), ALP, LDH, TBA, GSH and SOD were examined. The results show that SEM of An-AgNps has average particle size from 70 to 130nm. In the group treated with MTX; TC, TG, LDL-c, ALT, AST, ALP, LDH and TBA levels were significantly (P0.05) increased than NC, while, HDL-c, SOD and GSH levels were significantly (P0.05) decreased. On the other hand, An-AgNps + MTX treated groups were reversed the levels of all biomarkers similar to NC. In conclusion, the results show that An-AgNps has a protective effect on MTX-induced hepatotoxicity and oxidative stress.

Resumo O presente estudo teve como objetivo investigar o benefício de nanocompósito de antocianinas de arroz preto preparado (An-AgNps) contra a hepatotoxicidade induzida por metotrexato (MTX) em ratos. O nanocompósito de antocianinas foi preparado a partir da prata por meio da redução do íon metálico e caracterizado por IR e SEM. Os ratos em nosso experimento foram divididos em cinco grupos, e foram examinados o perfil lipídico sérico, as transaminases séricas (ALT e AST), ALP, LDH, TBA, GSH e SOD. Os resultados mostram que SEM de An-AgNps tem tamanho médio de partícula de 70 a 130 nm. No grupo tratado com MTX, os níveis de TC, TG, LDL-c, ALT, AST, ALP, LDH e TBA aumentaram significativamente (P 0,05) do que NC, enquanto os níveis de HDL-c, SOD e GSH diminuíram significativamente (P 0,05). Por outro lado, nos grupos tratados com An-AgNps + MTX, foram revertidos os níveis de todos os biomarcadores semelhantes ao NC. Em conclusão, os resultados mostram que o An-AgNps tem um efeito protetor contra a hepatotoxicidade induzida pelo MTX e o estresse oxidativo.

Potency Of Γ-Oryzanol-Rich Black Rice Bran (ORYZA Sativa L. Indica) Extract For Tyrosinase Inhibition

Objective: The objectives of this study were to quantify γ-oryzanol in an ethanolic extract of Oryza sativa L. Indica (black rice) bran and to evaluate its activity as a tyrosinase inhibitor. Methods: Black rice bran was extracted via maceration in 96% ethanol, and the γ-oryzanol concentration in the extract was measured through high-performance liquid chromatography. The applicability of the extract as a skin lightening agent was determined by evaluating its tyrosinase inhibition activity. Results: The dry rice bran contained 118.572 mg/g of γ-oryzanol, and the extract inhibited tyrosinase activity at an IC50 of 74.8%. Conclusion: The black rice bran extract was sufficiently potent for use in skin lightening formulations.

Rapid Isolation of Cyanidin 3-Glucoside and Peonidin 3-Glucoside from Black Rice (Oryza sativa) Using High-Performance Countercurrent Chromatography and Reversed-Phase Column Chromatography

Anthocyanins are water soluble plant pigments which are responsible for the blue, red, pink, violet colors in several plant organs such as flowers, fruits, leaves and roots. In recent years, anthocyanin-rich foods have been favored as dietary supplements and health care products due to diverse biological activities of anthocyanins including antioxidant, anti-allergic, anti-diabetic, anti-microbial, anti-cancer and preventing cardiovascular disease. High-performance countercurrent chromatography (HPCCC) coupled with reversed-phase medium pressure liquid chromatography (RP MPLC) method was applied for the rapid and efficient isolation of cyanidin 3-glucoside (C3G) and peonidin 3-glucoside (P3G) from black rice (Oryza sativa L., Poaceae). The crude black rice extract (500 mg) was subjected to HPCCC using two-phase solvent system composed of tert-butyl methyl ether/n-butanol/acetonitrile/0.01% trifluoroacetic acid (TBME/B/A/0.01% TFA, 1 : 3 : 1 : 5, v/v, flow rate - 4.5 mL/min, reversed phase mode) to give enriched anthocyanin extract (37.4 mg), and enriched anthocyanin extract was sequentially chromatographed on RP-MPLC to yield C3G (16.5 mg) and P3G (8.7 mg). The recovery rate and purity of isolated C3G were 76.0% and 98.2%, respectively, and those of P3G were 58.3% and 96.3%, respectively. The present study indicates that HPCCC coupled with RP-MPLC method is more rapid and efficient than multi-step conventional column chromatography for the separation of anthocyanins.

Black rice extract protected HepG2 cells from oxidative stress-induced cell death via ERK1/2 and Akt activation

BACKGROUND/OBJECTIVES: The objective of this study was to evaluate the protective effect of black rice extract (BRE) on tert-butyl hydroperoxide (TBHP)-induced oxidative injury in HepG2 cells. MATERIALS/METHODS: Methanolic extract from black rice was evaluated for the protective effect on TBHP-induced oxidative injury in HepG2 cells. Several biomarkers that modulate cell survival and death including reactive oxygen species (ROS), caspase-3 activity, and related cellular kinases were determined. RESULTS: TBHP induced cell death and apoptosis by a rapid increase in ROS generation and caspase-3 activity. Moreover, TBHP-induced oxidative stress resulted in a transient ERK1/2 activation and a sustained increase of JNK1/2 activation. While, BRE pretreatment protects the cells against oxidative stress by reducing cell death, caspase-3 activity, and ROS generation and also by preventing ERKs deactivation and the prolonged JNKs activation. Moreover, pretreatment of BRE increased the activation of ERKs and Akt which are pro-survival signal proteins. However, this effect was blunted in the presence of ERKs and Akt inhibitors. CONCLUSIONS: These results suggest that activation of ERKs and Akt pathway might be involved in the cytoprotective effect of BRE against oxidative stress. Our findings provide new insights into the cytoprotective effects and its possible mechanism of black rice against oxidative stress.

Black rice anthocyanidins prevent retinal photochemical damage via involvement of the AP-1/NF-kappaB/Caspase-1 pathway in Sprague-Dawley Rats

The effects of black rice anthocyanidins (BRACs) on retinal damage induced by photochemical stress are not well known. In the present study, Sprague-Dawley rats were fed AIN-93M for 1 week, after which 80 rats were randomly divided into two groups and treated with (n = 40) or without BRACs (n = 40) for 15 days, respectively. After treatment, both groups were exposed to fluorescent light (3,000 +/- 200 lux; 25degrees C), and the protective effect of dietary BRACs were evaluated afterwards. Our results showed that dietary BRACs effectively prevented retinal photochemical damage and inhibited the retinal cells apoptosis induced by fluorescent light (p < 0.05). Moreover, dietary BRACs inhibited expression of AP-1 (c-fos/c-jun subunits), up-regulated NF-kappaB (p65) expression and phosphorylation of IkappaB-alpha, and decreased Caspase-1 expression (p < 0.05). These results suggest that BRACs improve retinal damage produced by photochemical stress in rats via AP-1/NF-kappaB/Caspase-1 apoptotic mechanisms.

Phenolic compounds and antioxidant activity of rice

The aim of this work was to study the phenolic compounds identified in rice, their antioxidant activity and their potential beneficial effects on health. In vitro and in vivo studies evaluating the rice grains with different pericarp colour (light brown, red and black) showed potential beneficial effects on health related to the polyphenol content of the grain, such as reduction of oxidative stress, aid in the prevention of cancer, cardiovascular diseases and complications of diabetes, among others.

Identification and quantification of anthocyanin pigments in colored rice

Anthocyanin pigments from varieties of black, red and wild rice were identified and quantified to evaluate their potential as nutritional function, natural colorants or functional food ingredients. Anthocyanin extraction was conducted with acidified methanol with 0.1M HCl (85:15, v/v) and identification of anthocyanin, aglycone and sugar moieties was conducted by comparison with purified standards by HPLC, Ultraviolet-Visible absorption spectrophotometer and paper chromatography. Black and wild rice showed three different types of pigments by HPLC whereas red rice variety did not show any anthocyanins. Out of three pigments detected, one (peak 2) was characterized as cyanidin-3-glucoside (C3G) by comparison of spectroscopic and chromatographic properties with an authentic standard, and another (peak 3) was tentatively identified as cyanidin-fructoside on the basis of spectroscopic properties with lambdamax of aglycone in 1% HCl methanol at 537 nm, electrospray ionization mass spectra with major ions at 449 and 287 m/z and chromatographic properties. But another pigment (peak 1) has not been characterized. The most abundant anthocyanin in black and wild rice was C3G.

The Impact of Kinds of Dietary Grain and Dietary Lipid Level on the Glucose Metabolism and Antithrombogenic Capacity of Full Grown Obesity Induced Rats

This study was designed to evaluate impact of kinds of dietary grain and dietary lipid level on the glucose metabolism and antithrombogenic capacity in obesity induced rats. Total of 80 Sprague-Dawley male rats were raised for one month with control diet containing 50% (w/w) well-milled rice powder and 20% (w/w) of dietary lipids. The rats were blocked into 8 groups and raised for two months with diets containing well-milled rice, brown rice, black rice, or glutinous barley powder and 8 or 20% (w/w) of dietary lipids. The contents of total dietary fiber in experimental grains were in following order; glutinous barley > black rice > brown rice > well-milled rice. Weekly food intake were lower in glutinous barley group among all experimental groups. Body weight gain was high in high level of fat groups (20% w/w) than medium level of fat groups (8% w/w). Plasma glucose concentration was not different significantly in each groups. But brown rice group was a little lower than others. Plasma insulin concentration was lower in black rice and glutinous barley group than rice group. Plasma glucagon concentration did not differ significantly among all experimental groups. Hexokinase activities in skeletal muscle are different significantly according to level of dietary fat and grain variety factors. Brown rice group was significantly highest among all experimental groups in hexokinase activity. Plasma TXB2 concentrations in black rice and glutinous barley groups were lower as compared to rice and brown rice groups. Plasma 6-keto-PGF1alpha concentrations in glutinous barley group was higher as compared to others. In conclusion brown rice has a little lowering effect glucose concentration. Black rice and glutinous barley intakes enhance antithrombogenic capacity. It is suggested that the intakes of mixed gains are recommend.

STUDY OF THE RELATIVE BIOLOGICAL AVAILABILITY OF BRAN IRON OF BLACK RICE BY THE WAY OF HEMOGLOBIN REGENERATION IN RATS / 西安交通大学学报(医学版)

The bran of black rice contains 210～480 ppm iron, 50～70ppm zinc and 14.1% protein. In order to evaluate the bioavailability of bran iron, its relative biological availability (RBA) has been studied by means of the hemoglobin regeneration technique in anemic rats. All the rats were divided into five groups, the low-iron basal diet was supplemented with 23ppm Fe of ferrous sulfate in group A, 11.5% bran in group B, 11.5% bran plus 0.2% Vc in group C, 11.5% bran plus 2.3% cooked lean pork in group D and nothing in group E as the negative control The efficiencies of converting iron from the diet of group A, B, C, D into hemoglobin were 59%, 33%, 33% and 39% respectively and the relative biological availabilities were 100%, 56%, 56% and 66% respectively.

EFFECT OF BLACK RICE ANTHOCYANIN ON BIOCHEMICAL INDICATORS IN BLOOD AND MACROPHAGES OF RATS / 营养学报

Objective To investigate the immunomodulatory effect of black rice anthocyanin(BA) on biochemical indicators in blood and macrophages in rats.Method Twenty four female SD rats were randomly divided into 4 groups:control group,BA low,middle and high-dose groups(BAL 25;BAM 50;BAH 100 mg/kg bw).The control group was treated with normal saline,while BA groups were i.g.administered with defferent doses for 30 d.The blood biochemical indicators were detected by automatic biochemistry analyzer.The activities of lactate dehydrogenase(LDH),acid phosphatase(ACP),superoxide dismutase(SOD),and maleic dialdehyde(MDA) contents in peritoneal macrophage(PM) and alveolar macrophage(AM) were determined by biochemical methods.The ability of macrophages to phagocytose neutral red was measured by colorimetric method.Results The levels of urea nitrogen(UN),uric acid(UA),triglyceride(TG),total cholesterol(TC) and low density lipoprotein(LDL) in blood were reduced.The activities of ACP,LDH in PM were increased.and the activities of SOD in PM and AM were increased whereas MDA was reduced.The ability of PM and AM to phagocytose neutral red was strengthened significantly.Conclusion BA shows significant immunomodulatory effection blood biochemical indicators and macrophages in rats.