Antioxidant activity of fractionated pigmented Thai Hawm Gra Dang Ngah 59 rice bran hydrolysates: Pretreatment-assisted enzymatic extraction | Functional Foods in Health and Disease - Online ISSN: 2160-3855; Print ISSN: 2378-7007 Skip to main content Skip to main navigation menu Skip to site footer Open Menu Functional Foods in Health and Disease - Online ISSN: 2160-3855; Print ISSN: 2378-7007 Home Food Science Publisher Functional Food Center Current Archives About About the Journal Aims and Scope Contact Editing Services Editorial Team Express Peer Review Graphical Abstract Journal Insights Privacy Statement Submissions Announcements Search Search Register Login Home / Archives / Vol. 14 No. 6 (2024): June 2024 / Research Articles Antioxidant activity of fractionated pigmented Thai Hawm Gra Dang Ngah 59 rice bran hydrolysates: Pretreatment-assisted enzymatic extraction Authors Pornpen Panomwan Nantawat Tatiyaborworntham DOI: https://doi.org/10.31989/ffhd.v14i6.1376 Abstract Background: Hawm Gra Dang Ngah 59 rice (HGDN 59) is a pure line grown in the Takbai district, Narathiwat, located in the southern border province of Thailand. The previously reported HGDN 59 rice bran’s potential as a component rich in nutrients-especially high-quality protein, has not been exploited. There is also insufficient research data on biological activity and tested methods of exposing and releasing bioactive hydrolysates from HGDN 59 rice bran hydrolysates (HGDN 59-RBH).  Objectives: This study aimed to determine the antioxidative activity of three different pretreatments following ultrafiltration fractionation of HGDN 59-RBH.  Methods: HGDN 59 rice bran was defatted and pretreated with acid, alpha amylase, and water prior to digestion with consecutive pepsin and trypsin. HGDN 59-RBH was further fractionated by ultrafiltration into three molecular weight (MW) fractions: < 3 kDa, 3-5 kDa, and > 5 kDa. The whole RBH and three MW fractions were assessed to determine protein yield, protein recovery, total phenolic content, and the following antioxidative assays: 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferrous ion chelating activity, and ferric ion reducing antioxidation power (FRAP). Results: The highest protein content was obtained using pretreatment with acid, yielding 17.93± 0.08 g protein/100 g hydrolysates with 23.21 g/100 g protein recovery in defatted rice bran (DRB). The > 5 kDa fraction from the acid pretreatment-assisted enzymatic extraction of HGDN 59-RBH showed the highest phenolic content and scavenging activity against ABTS radical (2,2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid)) (EC50 0.669 mg/mL) and DPPH radical (2,2-diphenyl-1-picrylhydrazyl) (EC50 0.065 mg/mL) (P<0.05).  Conclusions: The findings reveal that subjecting HGDN 59-RBH to acid treatment before enzymatic breakdown is a successful approach to extracting peptides with potent antioxidant properties. Consequently, the resulting hydrolysates, rich in antioxidants, hold promise as valuable additions to food and nutraceutical formulations, enhancing their functional attributes. Keywords: Thai Hawm Gra Dang Ngah 59 rice bran, fractionated rice bran hydrolysates, pretreatment-assisted enzymatic extraction, antioxidant activity Downloads [Abstract] [Full Article] Published 2024-06-21 Issue Vol. 14 No. 6 (2024): June 2024 Section Research Articles License Copyright (c) 2024 Functional Foods in Health and Disease This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. Authors retain the copyright of their articles and grant the Functional Food Center (FFC) and its journals the right of first publication under the terms of the Creative Commons Attribution 4.0 International License. This license permits unrestricted use, distribution, and reproduction in any medium, including commercial use, provided the original author(s) and source are properly credited. Authors may post and share their published work freely, provided that the original publication in this journal is acknowledged. By submitting to this journal, authors confirm that their manuscripts are original, not under consideration elsewhere, and that they hold the necessary rights to grant this license. The Functional Food Center encourages open scientific exchange and allows derivative and extended works, provided attribution to the original publication is maintained. About the Journal      Editing Services      Graphical Abstract      Journal Insights        Submissions        Editorial Team       Privacy Statement        Contact        Current        Archives   Open Journal Systems Hosting and Support by: OpenJournalSystems.com