Optimization of Extraction,Compositional Analysis,and Functional Activities of Bound Polyphenols in Red Rice Bran Dietary Fiber
GU Yue
YU Qiang
Abstract：An extraction method for bound polyphenols(BPs)in red rice bran dietary fiber(RBDF)was developed and optimized,followed by analysis of the chemical composition and functional activities of RBDF-BPs.Conditions for BP extraction were optimized through single-factor experiments combined with the Box-Behnken response surface methodology.Alkaline hydrolysis was found to be more effective than acid hydrolysis in releasing RBDF-BPs,with a maximum total phenolic content(TPC)of 144.79 mg GAE/g DM obtained using the former method.A total of 21 polyphenolic compounds were identified by systematic quantitative analysis of RBDF-BPs using UPLC-ESI-QTOF-MS/MS,and 15 main components were subjected to targeted quantification using UPLC-ESI-QQQ-MS/MS.The in vitro antioxidant activities of RBDF-BPs were comprehensively assessed via DPPH·,ABTS+·,and·OH radical scavenging assays.RBDF-BPs exhibited significantly stronger in vitro antioxidant activities than vitamin C.RBDF-BPs also exerted dose-dependent inhibitory effects on both α-amylase and α-glucosidase,with the inhibitory effect on α-glucosidase being notably stronger(IC50=14.54 μg/mL).In the present study,the optimal extraction process of RBDF-BPs was determined,the composition and content of the chemical components of RBDF-BPs were elucidated,and their antioxidant activities and hypoglycemic potential were verified.The results of this study may serve as a scientific basis for the application of RBDF-BPs in functional foods and chronic disease prevention.
Keywords：red rice bran dietary fiberbound polyphenolsprocess optimizationantioxidant propertiesenzyme inhibitory activity
Publication Date：2025-10-20
Online Publishing Date：2025-12-03(First online date of this platform, not the publication date of the document)
Pages：11( 32-42 )