HPLC-DAD System-Based Phenolic Content Analysis andIn VitroAntioxidant Activities of Rice Bran Obtained from Aush Dhan (Oryza Sativa) of Bangladesh

Abstract

Food fibers are recently gaining interest in the scientific community for their beneficial role in various diseases such as diabetes, cardiovascular diseases, cancer and neurodegenerative diseases. Rice bran is an important source of food fibers. The objective of this study was to determine the presence of polyphenolic compounds in rice bran of Aush Dhan and determine the in vitro antioxidant activities in different extracts such as ethanol, ethylacetate and toluene extracts. Various antioxidant assays, including DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging, nitric oxide scavenging, hydrogen peroxide, reducing power, total phenolic content and total flavonoid content, were studied. Moreover, high-performance liquid chromatography (HPLC) was used to identify and quantify the phenolic compounds. The extracts showed effective DPPH free radical, hydrogen peroxide radical and nitric oxide scavenging activities. However, reducing power was not significant compared with the standard antioxidant ascorbic acid. Phytochemical analysis shows that rice bran contains reducing sugar, flavonoids and tannins. Furthermore, high-performance liquid chromatography coupled with photodiode array detector (HPLC-DAD) analysis showed that rice bran contains high amount of rutin hydrate along with epicatechin, which are strong natural antioxidants. These results suggest that rice bran contains high amount of antioxidants, which may be used as a source of polyphenolic compounds and can be used to treat chronic disease.

Antioxidant, Antidiabetic, and Antiobesity Properties, TC7-Cell Cytotoxicity and Uptake of Achyrocline satureioides (Marcela) Conventional and High Pressure-Assisted Extracts

“…Each of the samples were also eluted by RP-UHPLC according to Reza et al [ 12 ] with some modifications. RP-UHPLC UltiMate 3000 (Thermo Fisher Scientific, Massachusetts, USA) was used with a diode array detection (DAD detector).…”