查找使用阿拉丁产品的科研文献

A Neutral Polysaccharide from Spores of Ophiocordyceps gracilis Regulates Oxidative Stress via NRF2/FNIP1 Pathway

Yue Wang,Shixiang Wei,Hui Lian,Lingling Tong,Linhui Yang,Bo Ren,Dongsheng Guo,He Huang

Ophiocordyceps gracilis(O. gracilis) is a parasitic fungus used in traditional Chinese medicine and functional foods. In this study, a neutral heteropolysaccharide (GSP-1a) was isolated from spores ofO. gracilis, and its structure and antioxidant capacities were investigated. GSP-1a was found to have a molecular weight of 72.8 kDa and primarily consisted of mannose (42.28%), galactose (35.7%), and glucose (22.02%). The backbone of GSP-1a was composed of various sugar residues, including →6)-α-D-Manp-(1→, →2,6)-α-D-Manp-(1→, →2,4,6)-α-D-Manp-(1→, →6)-α-D-Glcp-(1→, and →3,6)-α-D-Glcp-(1→, with some branches consisting of →6)-α-D-Manp-(1→ and α-D-Gal-(1→. In vitro, antioxidant activity assays demonstrated that GSP-1a exhibited scavenging effects on hydroxyl radical (•OH), 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical cation (ABTS•+), and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•). Moreover, GSP-1a was found to alleviate H2O2-induced oxidative stress in HepG2 cells by reducing the levels of reactive oxygen species (ROS) and malondialdehyde (MDA), while enhancing the activities of superoxide dismutase (SOD). Furthermore, GSP-1a upregulated the mRNA expression of antioxidant enzymes such asHo-1,Gclm, andNqo1, and regulated the NRF2/KEAP1 and FNIP1/FEM1B pathways. The findings elucidated the structural types of GSP-1a and provided a reliable theoretical basis for its usage as a natural antioxidant in functional foods or medicine.Keywords:Ophiocordyceps gracilis;spores;polysaccharide;structural characterization;antioxidant activity