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.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2010年第19期157-160,共4页
Food Science
基金
科技部农业科技成果转化基金项目(2009GB23600523)
国家"863"计划项目(2007AA10Z312)
中央高校基本科研业务费专项(2009ZZ0021)
中国博士后基金项目(20070420775)
关键词
玉米淀粉
凝胶渗透色谱
激光光散射
分子质量分布
分子构象
corn starch
gel permeation chromatography
laser light scattering
molecular mass distribution
molecu-lar conformation