LAUSR

BACKGROUND Exopolysaccharide biopolymers produced by microorganisms are crucial to the environment. They contribute to areas such as the health and bionanotechnology sectors, food and cosmetic industries as gelling agents, and environmental sector as flocculants owing to their biodegradability and non-toxic nature. The current study aimed to isolate the fraction of released exopolysaccharides (rEPS) by Bacillus velezensis SN-1 from Chinese Da-Jiang. RESULTS The Mw of the major isolated component, rEPS-2, was 202 kDa, and its monosaccharide composition included mannose, glucose, and galactose at a molar ratio of 0.38: 0.30: 0.32. Further, the rEPS-2 was characterized using methylation analysis and 1D/2D NMR spectroscopy. In vivo hepatoprotective effects indicated that rEPS-2 could alleviate CCl4 -induced liver injury in mice by lowering the activities of AST, ALT and the MDA levels. rEPS-2 can increase the expression of antioxidant genes HO-1, GCLC and NQO1 in the Nrf2/ARE signaling pathway, thereby increasing the activity of antioxidant enzymes SOD, GSH-Px and CAT in liver cells. Furthermore, the rEPS-2 can be used and modulate the gut microbiota of mice with liver injury caused by CCl4 . CONCLUSIONS These results suggest that rEPS-2 has promising potential to serve as hepatoprotective agents. This article is protected by copyright. All rights reserved.