Effect of sucrose on antioxidant activities and other health-related micronutrients in gamma-aminobutyric acid (GABA)-enriched sprouting Southern Vietnam brown rice

Improving the nutritional quality of germinated brown rice (GBR) is important for the population consuming rice as part of the daily diet to offer health benefits. In this study, a set of popularly grown 79 rice varieties in Southern Vietnam was evaluated to identify the potential materials for producing gamma-aminobutyric acid (GABA)-enriched GBR. Enhancing antioxidant components, antioxidant activities, and other health-promoting micronutrients by sucrose treatment were also investigated in both white and red GBR. The results indicated that OM457 (white rice) and TN11 (red rice)-derived GBR had the highest GABA content of 105.68 mg GABA/100 g F.W and 47.68 mg GABA/100 g F.W among investigated rice varieties, respectively. Sucrose at 50 mM, in general, boosted total phenolic compounds, total flavonoids, anthocyanin content, thereby increasing antioxidant activities in both these GBR. Moreover, GC-MS-based metabolomic analysis indicated that GABA accumulation under sucrose treatment was rice pericarp/variety-specific. Also, sucrose stimulated the accumulation of other health-benefiting metabolites and free sugars. Altogether, the results in this study indicate that sucrose is an effective elicitor for improving the nutritional value in GBR, facilitating for production of ready-to-eat GBR with health-promoting benefits.