关键词: 玉米醇溶蛋白, 糖基化, 葡聚糖, 结构, 功能性

Abstract: Zein and dextran (DX) with different molecular masses (6, 20, 40 and 70 kDa) were prepared into zein-DX glycosylation products by a wet heating method in the present research. The purpose was to examine the effect of DX with different molecular masses on structural and functional properties of zein glycosylation products. As molecular mass of DX increased, the degree of graft and the browning intensity reduced, which indicated that DX with lower molecular mass was easier to react with zein to form glycosylation products with higher solubility and lower surface hydrophobicity. Glycosylation could improve the emulsifying activity index (EAI) and emulsifying stability index (ESI) of zein. With the increase in the molecular mass of DX, the EAI of zein-DX glycosylation products gradually decreased and the ESI gradually increased. Moreover, the covalent binding affinity of DX with high molecular mass could lead to the transformation of the ordered α-helix structure to the unordered β-sheet and random coil structure, which resulted in more flexible and looser protein conformation.

Key words: zein, glycosylation, dextran, structure, functional properties