BackgroundPeach gum (PG) is an exudate of the peach tree (Prunus persica of the Rosaceae family), which consists primarily of polysaccharides with a large molecular weight and branching structure. Consequently, PG can only swell in water and not dissolve directly, which severely limits its application. Current conventional extraction methods for PG polysaccharide (PGPS) are time‐consuming and inefficient. This study investigated the impact of ultrasonic‐assisted extraction (UAE) on PGPS structure and conformation, as well as their relationship to hypoglycemic activity in vitro.ResultsCompared to conventional aqueous extraction, UAE enhanced PGPS yield from 28.07%–32.83% to 80.37%–84.90% (w/w) in 2 h. It drastically decreased the molecular size and conformational parameters of PGPS, including Mw, Mn, Rg, Rh and [η] values. PGPS conformation converted from extended molecules to flexible random coil chains or compact spheres with no obvious primary structure alteration. Furthermore, UAE altered the flow behaviour of PGPS solution from non‐Newtonian fluid to Newtonian fluid. As a result, PGPS treated with ultrasonic displayed weaker inhibitory activity than those untreated, mostly because UAE weakens the binding strength of PGPS to α‐glucosidase. However, this negative effect of UAE on PGPS activity was compensated by the increased solubility of polysaccharide. This enabled PGPS to achieve a wider range of doses.ConclusionUAE is capable of degrading PGPS efficiently while preserving its primary structure, resulting in a Newtonian fluid solution. The degraded PGPS conformation display a consistent correlation with their inhibitory effect on α‐glucosidase activity.This article is protected by copyright. All rights reserved.

中文翻译：

---

超声辅助提取对桃胶多糖体外降血糖活性及其构象转化的影响

背景桃胶（PG）是桃树的分泌物（桃蔷薇科），主要由具有大分子量和支化结构的多糖组成。因此，PG只能在水中膨胀而不能直接溶解，严重限制了其应用。目前传统的PG多糖（PGPS）提取方法既耗时又低效。本研究调查了超声辅助提取 (UAE) 对 PGPS 结构和构象的影响及其与降血糖活性的关系体外结果与传统水萃取相比，UAE将PGPS产率从28.07%–32.83%提高到80.37%–84.90%（重量/重量）在2小时内。它大大降低了 PGPS 的分子大小和构象参数，包括中号w,中号n,右G,右H和 [η] 值。 PGPS构象从延伸的分子转变为柔性的无规卷曲链或致密的球体，没有明显的一级结构改变。此外，UAE 将 PGPS 溶液的流动行为从非牛顿流体更改为牛顿流体。结果，经超声波处理的 PGPS 表现出比未经处理的 PGPS 更弱的抑制活性，这主要是因为 UAE 削弱了 PGPS 与 α-葡萄糖苷酶的结合强度。然而，UAE 对 PGPS 活性的这种负面影响可以通过多糖溶解度的增加得到补偿。这使得 PGPS 能够实现更广泛的剂量。结论UAE 能够有效降解 PGPS，同时保留其主要结构，从而产生牛顿流体溶液。降解的PGPS构象与其对α-葡萄糖苷酶活性的抑制作用表现出一致的相关性。本文受版权保护。版权所有。