title: Enhancement of exo-polysaccharide production and antioxidant activity in submerged cultures of Inonotus obliquus by lignocellulose decomposition.
abstract: We reported that lignocellulose decomposition can be used to facilitate the production of bioactive polysaccharides from submerged culture of Inonotus obliquus. Exo-polysaccharide (EPS) production and antioxidant activity by Inonotus obliquus was enhanced by employing lignocellulose decomposition in a corn straw-containing submerged fermentation. A significant increase in the EPS production and hydroxyl radical scavenging activity from 1.09 ± 0.01 g/l and 72.3 ± 1.9% in a basal medium to 1.38 ± 0.02 g/l and 82.7 ± 0.5% in a corn straw-containing medium was obtained. A synchronized effect between lignocellulose decomposition and malondialdehyde presenting hydroxyl radical concentration in the fermentation broth was identified. The adding of thiourea, a hydroxyl radical-scavenging reagent, suppressed malondialdehyde generation and lowered the lignocellulose decomposition rate. Correspondingly, the EPS production and hydroxyl radical scavenging activity decreased to 1.26 g/l and 74%. The EPS obtained from the corn straw-containing medium also presented the strongest superoxide radical scavenging activity. The monosaccharide components of the EPS from the corn straw-containing medium are rhamnose, arabinose, xylose, mannose, glucose, and galactose with molar proportions at 3.0, 3.0, 0.9, 46.6, 11.4, and 35.1%, respectively, which are largely different from the molar proportions of the EPS from the basal medium.
authors.affiliation: School of Science, Zhejiang Sci-Tech University, Hangzhou, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Chen
authors.forename: Mingchao
authors.initials: M
authors.lastname: Yan
authors.forename: Jinwei
authors.initials: J
authors.lastname: Zhu
authors.forename: Xiangqun
authors.initials: X
authors.lastname: Xu
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D001487:Basidiomycota / Q000737:chemistry / Q000378:metabolism; D003470:Culture Media / Q000032:analysis; D005285:Fermentation; D017665:Hydroxyl Radical / Q000378:metabolism; D008031:Lignin / Q000378:metabolism*; D008315:Malondialdehyde / Q000032:analysis / Q000378:metabolism; D009005:Monosaccharides / Q000032:analysis; D011134:Polysaccharides / Q000096:biosynthesis* / Q000378:metabolism*; D013481:Superoxides / Q000378:metabolism; D013997:Time Factors; D003313:Zea mays / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D003470:Culture Media; D009005:Monosaccharides; D011134:Polysaccharides; D013481:Superoxides; C036909:lignocellulose; D017665:Hydroxyl Radical; D008315:Malondialdehyde; C007916:hemicellulose; D008031:Lignin