Enhancing GABA and Antioxidant Bioaccessibility in Germinated Brown Rice: Ultrasonic-Assisted Cellulase Pretreatment...

Area of Science:

• Food Science and Technology
• Biotechnology
• Nutritional Science

Background:

• Germinated brown rice (GBR) is a functional food valued for gamma-aminobutyric acid (GABA) and antioxidants.
• The dense bran structure of GBR limits the bioavailability of its beneficial compounds.
• Green technologies are sought to improve the nutritional profile and processing of GBR.

Purpose of the Study:

• To optimize ultrasonic-assisted cellulase pretreatment for GBR.
• To enhance GABA content and antioxidant activity in GBR.
• To evaluate the bioaccessibility and processing efficiency of pretreated GBR.

Main Methods:

• Response Surface Methodology (RSM) and Artificial Neural Network-Genetic Algorithm (ANN-GA) were used to model process variables (ultrasonic time, cellulase concentration).
• Optimized pretreatment conditions were applied to GBR.
• In vitro digestion assays were performed to assess GABA and phenolic compound bioaccessibility.

Main Results:

• The ANN-GA model showed superior predictive accuracy over RSM.
• Optimized pretreatment significantly increased GABA content, total phenolics, and antioxidant activity in GBR.
• Pretreated GBR demonstrated reduced optimal cooking time and enhanced in vitro bioaccessibility of GABA (115.74%) and total phenolics (128.53%).

Conclusions:

• Ultrasonic-assisted cellulase pretreatment is an effective green technology for enhancing GBR's nutritional value.
• This method improves GABA and antioxidant bioaccessibility, offering health benefits.
• The optimized process is sustainable and scalable for producing functional GBR-based foods with improved processing efficiency.