Jo Myeongsu, Qi Jing, Du Zhenjiao, Li Yonghui, Shi Yong-Cheng
Department of Grain Science and Industry, Kansas State University, Manhattan, KS 66506, USA; Center for Food and Bioconvergence, Seoul National University, Gwanakgu, Seoul 08826, Republic of Korea.
Department of Grain Science and Industry, Kansas State University, Manhattan, KS 66506, USA.
Carbohydr Polym. 2024 Jul 1;335:122070. doi: 10.1016/j.carbpol.2024.122070. Epub 2024 Mar 18.
Starches are hydrolyzed into monosaccharides by mucosal α-glucosidases in the human small intestine. However, there are few studies assessing the direct digestion of starch by these enzymes. The objective of this study was to investigate the changes in the structure and enzyme binding of starches during in vitro hydrolysis by mammalian mucosal enzymes. Waxy maize (WMS), normal maize (NMS), high-amylose maize (HAMS), waxy potato (WPS), and normal potato (NPS) starches were examined. The order of the digestion rate was different compared with other studies using a mixture of pancreatic α-amylase and amyloglucosidase. NPS was digested more than other starches. WPS was more digestible than WMS. Hydrolyzed starch from NPS, NMS, WPS, WMS, and HAMS after 24 h was 66.4, 64.2, 61.7, 58.7, and 46.2 %, respectively. Notably, a significant change in the morphology, reduced crystallinity, and a decrease in the melting enthalpy of the three starches (NPS, NMS, and WPS) after 24 h of hydrolysis were confirmed by microscopy, X-ray diffraction, and differential scanning calorimetry, respectively. The bound enzyme fraction of NPS, NMS, and WPS increased as hydrolysis progressed. In contrast, HAMS was most resistant to hydrolysis by mucosal α-glucosidases in terms of digestibility, changes in morphology, crystallinity, and thermal properties.
淀粉在人类小肠中被黏膜α-葡萄糖苷酶水解为单糖。然而，评估这些酶对淀粉直接消化作用的研究很少。本研究的目的是调查淀粉在体外被哺乳动物黏膜酶水解过程中的结构变化和酶结合情况。研究了糯玉米（WMS）、普通玉米（NMS）、高直链玉米（HAMS）、糯马铃薯（WPS）和普通马铃薯（NPS）淀粉。与使用胰α-淀粉酶和淀粉葡萄糖苷酶混合物的其他研究相比，消化速率的顺序有所不同。NPS比其他淀粉消化得更多。WPS比WMS更易消化。24小时后，NPS、NMS、WPS、WMS和HAMS的水解淀粉分别为66.4%、64.2%、61.7%、58.7%和46.2%。值得注意的是，分别通过显微镜、X射线衍射和差示扫描量热法证实，三种淀粉（NPS、NMS和WPS）在水解24小时后形态发生显著变化、结晶度降低且熔融焓下降。随着水解的进行，NPS、NMS和WPS的结合酶部分增加。相比之下，就消化率、形态、结晶度和热性质的变化而言，HAMS对黏膜α-葡萄糖苷酶的水解最具抗性。
