Most studies have primarily focused on the effects of individual sources of pectin or polyphenols on starch digestibility. However, the interactions between pectin and polyphenols in digestive fluids may influence their inhibitory capacity against starch digestion by modulating α-amylase activity (αAA), a relationship that remains poorly understood. This study aims to clarify how pectin affects starch digestion when combined with mulberry fruit powder (MFP), mulberry polyphenol extract (MPE), and rutin (the main phenolic compound in MPE). Results showed that the combination of pectin and MFP initially inhibited αAA but later enhanced it. The combination of pectin and MPE consistently showed stronger inhibition of αAA than MPE alone throughout digestion; similar results were observed for the pectin-rutin combination, though the pectin-MPE pairing exhibited greater inhibition than the latter. Pectin's enhanced inhibitory effect on starch digestion may arise from its interactions with α-amylase, starch, and polyphenols through hydrophobic interactions, hydrogen bonding, and non-covalent forces.

中文翻译：

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桑树、果胶、芦丁及其组合对淀粉消化过程中 α-淀粉酶活性和葡萄糖吸收的影响


大多数研究主要集中在果胶或多酚的个别来源对淀粉消化率的影响上。然而，消化液中果胶和多酚之间的相互作用可能通过调节 α-淀粉酶活性 （αAA） 来影响它们对淀粉消化的抑制能力，但这种关系仍然知之甚少。本研究旨在阐明果胶与桑果粉 （MFP）、桑树多酚提取物 （MPE） 和芦丁（MPE 中的主要酚类化合物）结合使用时如何影响淀粉消化。结果表明，果胶和 MFP 的组合最初抑制了 αAA，但后来增强了 αAA。在整个消化过程中，果胶和 MPE 的组合始终显示出比单独使用 MPE 更强地抑制 αAA;果胶-芦丁组合观察到类似的结果，尽管果胶-MPE 配对表现出比后者更大的抑制作用。果胶对淀粉消化的增强抑制作用可能源于它与 α-淀粉酶、淀粉和多酚通过疏水相互作用、氢键和非共价力的相互作用。