AUTHOR=Li Shiwei , Wang Yingna , Dun Weipeng , Han Wanqing , Xu Chunping , Sun Qi , Wang Zichao 

TITLE=Effect of ultrasonic degradation on the physicochemical property and bioactivity of polysaccharide produced by Chaetomium globosum CGMCC 6882

JOURNAL=Frontiers in Nutrition

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2022.941524

DOI=10.3389/fnut.2022.941524

ISSN=2296-861X

ABSTRACT=Similar to enzymatic process, there might also be active fragment in polysaccharides, how to obtain which is important for investigating the bioactivity and pharmacological mechanism of polysaccharides. Presently, a Gynostemma pentaphyllum endophytic fungus Chaetomium globosum CGMCC 6882 polysaccharide (GCP) was degraded by ultrasonic treatment, two polysaccharide fragments of GCP-F1 and GCP-F2 were obtained. Physicochemical results showed that GCP-F1 and GCP-F2 had the same monosaccharide composition of arabinose, galactose, glucose, xylose and mannose and glucuronic acid compared to GCP with slightly different molar ratios. However, weight-average molecular weights of GCP-F1 and GCP-F2 decreased from 8.093 × 104 Da (GCP) to 3.158 × 104 Da and 1.027 × 104 Da, respectively. In vitro scavenging assays illustrated that GCP-F1 and GCP-F2 had higher antioxidant activity against ABTS radical, DPPH radical, superoxide anions and hydroxyl radical than GCP, the order was GCP < GCP-F1 < GCP-F2. Meanwhile, antibacterial tests showed that ultrasonic degradation increased the antibacterial activity of GCP-F1 compared to GCP, but GCP-F2 almost lost its antibacterial activity with further ultrasound treatment. Changes of the antioxidant and antibacterial activities of GCP-F1 and GCP-F2 might related to the variation of their molecular weights.