CHARACTERISATION AND FUNCTIONAL STUDIES OF RICE PROTEINS

摘要

Rice is one of the most important crops all over the world. However, dough-making quality of rice storage proteins is very poor compared to wheat. Structure and properties of the storage proteins of wheat and rice are significantly different. The storage protein composition of rice shows more similarities to legume proteins than to wheat, barley and rye. While the most abundant storage proteins are member of the prolamin family in cereals, the major protein components in rice, called glutelin, belongto the globulin group. Glutelins the major rice storage proteins are soluble in diluted acid or alkaline solution. The subunits are able to form large macromolecule complexes stabilised by disulfide bonds and hydrophobic interactions (Utsumi, 1992). Itwas assumed that besides hydrogen and disulfide bonding extensive aggregation and glycosylation may also be partly responsible for the limited solubility of the rice polymeric glutelin fraction. Rice glutelins are synthesized as precursor polypeptides, which are posttranslationally cleaved into two smaller subunits.