Sew, Y. S., Abd Rashid, M. R., Ahmad, M. A., AbuBakar, N., Zainal Abidin, R. A., Ab Razak, M. S. F. and Simoh, S.
Abstract
Folate (vitamin B9) is vital for growth and development, but its deficiency especially in populations relying heavily on low-folate staple foods like polished rice poses significant health risks, making rice biofortification with natural, more bioavailable folates a crucial strategy for improving global nutrition. This study aimed to identify key functional genes involved in the folate biosynthesis pathway for rice biofortification. We assessed the antioxidant activities of four pigmented rice varieties (PH 9, BALI, MRQ 100, and MRM 16) and two non-pigmented rice varieties (MRQ 76 and MR 297) using antioxidant assays (i.e. TPC, DPPH and FRAP), along with measurements of folate biosynthesis gene expression levels using quantitative PCR method. Antioxidant activities were significantly higher in the pigmented than the non-pigmented ones (p <0.05). One-way ANOVA with post-hoc analysis revealed that four folate biosynthesis genes, namely Os01g0238500, Os06g0699700, Os07g0618500, and Os12g0623800 were differentially expressed between rice with distinct pigmentation (p <0.05). Spearman’s rho correlation analysis indicated a significant and positive correlation between antioxidant activities and the expression levels of aminodeoxychorismate synthase/glutamine amidotransferase (ADCS) (Os06g0699700) and dihydropterin pyrophosphokinase/ dihydropteroate synthase (HPPK/ DHPS) (Os07g0618500) (p <0.05). These findings suggest that these two genes play a crucial role in folate biosynthesis in rice and may serve as promising targets for enhancing folate content through biofortification.
Keywords: antioxidant activity, biofortification, folate, gene expression, rice
.JPG)
