Effect of sprouting on amylases activities and amylose content of ten inbred rice varieties in Nigeria

Abstract

Background: Federal Agricultural Rice Oryza Sativa (FARO) variety of rice, have been developed in Nigeria using interbreeding techniques. Rice like other cereals is a good source of industrial amylases. The aim of this study is to determine the effect of sprouting on the amylase activities and amylose content of ten randomly selected FARO rice varieties, which includes FARO 15, 16, 20, 22, 30, 45, 47, 55, 61 and 62. Methods: The rice varieties were sprouted for twelve (12) days according to standard procedures, in order to determine the amylases activities and their amylose content. The alpha, beta and glucoamylase activities and amylose content of the FARO rice samples were determined daily during sprouting. Results: The result showed that α-amylase activity of the FARO rice samples increased from the 3rd to 10th day of sprouting. The highest α-amylase activity was attained on the 5th and 6th days which ranges from 50.18×10-3-52.17x 10-3 U/ml. The β-amylase activity for the FARO rice samples increased from the 3rd to the 8th day of sprouting. The highest β-amylase activity was attained on days 5 and 6, which range from 45.01×10-3- 48.07×10-3 U/ml. The glucoamylase activity for most of the FARO rice sample increased from the 3rd to the 7th day of sprouting; the highest activity was on day 5 which was 100×10-3 U/ml. The result of the effect of sprouting on the amylose content of the FARO rice samples revealed that as the number of days of sprouting increased the amylose content decreased. The amylase activities correlated significantly with the amylose content of the FARO rice varieties used in this study. Conclusion: From this study, sprouting has shown to be a cheap and economical way of improving amylase yields and modifying the amylose content of FARO rice samples for better application in food industries and confectioneries.