The aim of this study was to investigate the effects of ultrasound degradation on the physicochemical, rheological and antioxidant properties of Sargassum pallidum polysaccharides (SpPS). The results indicated that the ultrasound irradiation could significantly decrease the average molecule weight (MW), and particle size (Zavg) of native SpPS. The degradation pattern of SpPS was closely fitted to the first-order polymer degradation (random chain scission). The primary structure of SpPS before and after ultrasound degradation was not changed, and scanning electron microscopy (SEM) analysis showed that the morphology of SpPS was different from those of the degraded SpPS fractions. Rheological analysis indicated that the degraded SpPS solutions exhibited lower apparent viscosities than native SpPS solution at the same concentration, while the elasticity of the degraded fractions at a certain extent was enhanced. Furthermore, appropriately degraded SpPS fractions exhibited stronger DPPH and ABTS scavenging activity.

中文翻译：

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超声波降解对马尾藻多糖的理化、流变和抗氧化特性的影响。


本研究的目的是研究超声降解对马尾藻多糖（SpPS）的理化、流变和抗氧化特性的影响。结果表明，超声辐射可以显着降低天然 SpPS 的平均分子量 (MW) 和粒径 (Zavg)。 SpPS 的降解模式与一级聚合物降解（无规断链）密切相关。超声降解前后SpPS的一级结构没有改变，扫描电子显微镜（SEM）分析表明SpPS的形态与降解后的SpPS组分不同。流变学分析表明，相同浓度下，降解后的SpPS溶液表现出比天然SpPS溶液更低的表观粘度，同时降解部分的弹性在一定程度上有所增强。此外，适当降解的 SpPS 级分表现出更强的 DPPH 和 ABTS 清除活性。