机构地区: 华南理工大学轻工与食品学院
出 处: 《食品科学》 2010年第19期157-160,共4页
摘 要: 采用凝胶渗透色谱(GPC)和十八角度激光光散射(MALLS)技术,以二甲基亚砜为流动相测定蜡质玉米淀粉、普通玉米淀粉、直链/支链比1:1的高直链玉米淀粉(G50)、直链/支链比4:1的高直链玉米淀粉(G80)的分子质量及其分布以及在二甲基亚砜(DMSO)溶液中的均方根旋转半径和构象。结果表明:分子质量最大的是蜡质玉米淀粉,其重均分子质量达到了1.416×108g/mol,其次是普通玉米淀粉2.744×107g/mol与G501.026×107g/mol,最小的是G80的3.992×106g/mol;均方根旋转半径也是随着直链淀粉含量的增加依次减小;蜡质玉米淀粉在DMSO溶液中的构象是较为紧密的无规则卷曲型,其他3种玉米淀粉的构象均为球型。 The determination of molecular mass,molecular mass distribution,mean square radius of gyration and conformation using gel permeation chromatography coupled with multi-angle laser light scattering (GPC-MALLS) with refractive index detector with DMSO as the mobile phase was carried out for waxy,common,G50 (with 50% amylase content) and G80 (with 80% amylase content) corn starches. The results showed that the weight-average molecular masses (Mw) of waxy,normal,G50 and G80 corn starches were 1.416 × 108,2.744 × 107,1.026 × 107,3.992 × 106 g/mol,respectively. Similarly,higher-amylose corn starch had smaller mean square radius of gyration. The conformation of waxy corn starch was compact random coil and the three others were compact globular structure in DMSO.