Obtaining proteins and protein hydrolysate antioxidants from cold-pressed defatted rice Bran by ethanol-modified mild subcritical water extraction

Hemathulin, S., Posri, W., Chaoruangrit, A. and Thawornchinsombut, S. (2026) Obtaining proteins and protein hydrolysate antioxidants from cold-pressed defatted rice Bran by ethanol-modified mild subcritical water extraction. Journal of Food Science and Technology. ISSN 0022-1155

Text W Posri Obtaining proteins and protein hydrolysate OCR UPLOAD 1.pdf - Accepted Version Restricted to Repository staff only until 18 February 2027. Download (1MB) | Request a copy

Abstract

This study aimed to elevate the recovery of bioactive compounds from a cold-pressed defatted rice bran using ethanol-enhanced mild subcritical alkaline water (m-SAWEtOH) treatment. Optimal conditions of m-SAWEtOH to obtain extracts rich in protein were investigated. Three variables were assessed using a response surface methodology (RSM) in a Box-Behnken Design (BBD) with extraction temperature (x1, 110–120 °C), time (x2, 30–90 min), and ethanol level (x3, 0–70%). The protein-rich sediment (Prot-Sed) was precipitated by adjusting the extracted supernatant to 75% ethanol. The optimum m-SAWEtOH conditions for the Prot-Sed extraction were 120 °C, 38.9% ethanol, for 90 min. Ethanol enhanced the m-SAW, providing the Prot-Sed with higher protein, total phenolic content, and antioxidant activity (FRAP assay). Additionally, the 2-step process of m-SAWEtOH and protease hydrolysis increased the recovery of protein and phenolics by 1.93-fold and 10.42-fold, respectively, concomitant with an increase in antioxidant capacity. Amino acids (His, Leu, Met, Trp, and Val) and polyphenols (protocatechuic acid, p-coumaric acid, ferulic acid, and sinapic acid) possessing antioxidant capacity were presented in the Prot-Sed hydrolysate. The findings demonstrated that m-SAWEtOH is a green process that improves the release of bioactive components, adding value to biomaterials.

Item Type:	Article
Additional Information:	Final published version not available from this repository. Authors accepted manuscript available to view from this repository from 18/02/2027. Springer terms of use apply: https://www.springernature.com/gp/open-science/policies/accepted-manuscript-terms
Keywords:	Mild subcritical alkaline water–ethanol extraction, Cold-pressed defatted rice bran, Response surface methodology, Protein hydrolysates, Antioxidant activity
Divisions:	Harper Food Innovation
Depositing User:	Miss Anna Cope
Date Deposited:	10 Mar 2026 14:22
Last Modified:	10 Mar 2026 14:22
URI:	https://hau.repository.guildhe.ac.uk/id/eprint/18337

Actions (login required)

Edit Item