Takahama Umeo, Ansai Toshihiro, Hirota Sachiko
Emeritus Professor of Kyushu Dental University, Kitakyushu 803-8580, Japan.
Division of Community Oral Health Development, Kyushu Dental University, Kitakyushu 803-8580, Japan.
Heliyon. 2022 Nov 17;8(11):e11605. doi: 10.1016/j.heliyon.2022.e11605. eCollection 2022 Nov.
Polyphenols in plant can interact with amylose and amylopectin in different ways affecting their hydrolysis by α-amylase. Pancreatin liberated starch from non-glutinous rice flour heated with and without an aqueous extract of sorghum seeds, and hydrolyzed the liberated starch. The hydrolysis of the liberated starch was slowed down by the sorghum extract. Then, the liberated starch was fractionated into soluble starch and suspendable starch. In the soluble starch, amylose hydrolysis was slowed down more significantly than amylopectin hydrolysis, and in the suspendable starch, the hydrolysis of amylopectin was slowed down efficiently by the sorghum extract. It is discussed that (i) the slowdown in the former might be due to the binding of sorghum components including procyanidins to amylose, and that (ii) the slowdown in the latter might be due to the complex formation between amylopectin and shorter amylose combined with the sorghum components. The contribution of amylose to the slowdown was supported by the result that the sorghum extract inhibited the starch hydrolysis only slightly in glutinous rice flour, the starch of which was almost composed of amylopectin. It was proposed a possible mechanism of the slowdown of amylopectin hydrolysis in suspendable starch by shorter amylose combined with the sorghum components.
植物中的多酚可以通过不同方式与直链淀粉和支链淀粉相互作用，从而影响它们被α-淀粉酶水解的过程。胰酶从经高粱种子水提取物加热和未加热的非糯米粉中释放出淀粉，并水解释放出的淀粉。高粱提取物减缓了释放出的淀粉的水解。然后，将释放出的淀粉分离为可溶性淀粉和可悬浮淀粉。在可溶性淀粉中，直链淀粉的水解比支链淀粉的水解减缓得更显著；而在可悬浮淀粉中，高粱提取物有效地减缓了支链淀粉的水解。讨论认为：（i）前者水解减缓可能是由于包括原花青素在内的高粱成分与直链淀粉结合；（ii）后者水解减缓可能是由于支链淀粉与较短直链淀粉和高粱成分形成了复合物。高粱提取物在糯米粉（其淀粉几乎全部由支链淀粉组成）中对淀粉水解的抑制作用很小，这一结果支持了直链淀粉对水解减缓的作用。提出了较短直链淀粉与高粱成分结合导致可悬浮淀粉中支链淀粉水解减缓的一种可能机制。
