关键词: 离子强度, 大豆11S球蛋白, 表面疏水性, 结构

Abstract: Solubility, surface hydrophobicity (H0), Zeta potential, particle size and molecular structure of 11S glycinin at different ionic strengths were determined. The effect of ionic strength on H0 and structure of 11S glycinin was explored. Results showed that the solubility and absolute value of Zeta potential were decreased whereas H0 and average particle size were increased with increasing ionic strength from 0 to 0.9. Moreover, the content of α-helix structure was decreased and the content of β-sheet structure was increased. The tyrosine and tryptophan residues of the protein was transformed from “embedding” to “exposure” state as the ionic strength was increased, leading to an increase of H0. The disulfide bond configuration of 11S glycinin at different ionic strengths was changed, possibly affecting its H0.

Key words: ionic strength, 11S glycinin, surface hydrophobicity, structure