title: High-Level Production of Exopolysaccharides by a Cosmic Radiation-Induced Mutant M270 of the Maitake Medicinal Mushroom, Grifola frondosa (Agaricomycetes).
abstract: A new Grifola frondosa mutant, M270, was successfully isolated for high production of exopolysaccharides (EPSs) using cosmic radiation-induced mutagenesis. We found that the mutant M270 had a clearer and thicker EPS layer (~10 µm) adhering to mycelia than those of its parent strain 265 after Congo red staining. In the 20-L batch fermentation for M270, 10.3 g/L of EPS and 17.9 g/L of dry mycelia biomass were obtained after 204 hours of fermentation. Furthermore, a main water-soluble fraction (EP1) in the EPS was purified from M270 and then confirmed to be heteroglycan-protein complex with 91% (w/w) total carbohydrates and 9% (w/w) total proteins. Four kinds of monosaccharide-D-mannose, D-glucosamine, D-glucose, and D-xylose-were detected in EP1 with a molar ratio of 17.6:1.8:100:2.5. The molecular mass of the main component in EP1 was 8.9 kDa. The EPS from M270 significantly inhibited the growth of sarcoma 180 solid tumors in mice. This G. frondosa M270 mutant could serve as a better candidate strain for polysaccharide production.
authors.affiliation: Shandong Province Key Laboratory of Applied Mycology, School of Life Sciences, Qingdao Agricultural University, Qingdao, People's Republic of China.
authors.forename: Chen
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Institute of Microbiology, P.O. Box 61, Beijing Forestry University, Beijing 100083, China; Shandong Provincial Key Laboratory of Applied Mycology, Qingdao Agricultural University, Qingdao 266109, China; College of Life Sciences, Qingdao Agricultural University, Qingdao, China.
authors.forename: Xue-Mei
authors.initials: XM
authors.lastname: Tian
authors.affiliation: Shandong Province Key Laboratory of Applied Mycology, Qingdao Agricultural University, Qingdao, China; College of Life Sciences, Qingdao Agricultural University, Qingdao, China.
authors.forename: Guang-Yuan
authors.initials: GY
authors.lastname: Wang
authors.affiliation: Shandong Province Key Laboratory of Applied Mycology, Qingdao Agricultural University, Qingdao, China; College of Life Sciences, Qingdao Agricultural University, Qingdao, China.
authors.forename: Ai-Rong
authors.initials: AR
authors.lastname: Song
authors.affiliation: College of Agronomy and Plant Protection, Qingdao Agricultural University, Qingdao, China.
authors.forename: Wen-Xing
authors.initials: WX
authors.lastname: Liang
mesh_terms: D000818:Animals; D062610:Fungal Polysaccharides / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins; D015966:Gene Expression Regulation, Fungal; D048691:Grifola / Q000737:chemistry* / Q000235:genetics*; D051379:Mice; D009154:Mutation; D009374:Neoplasms, Experimental / Q000188:drug therapy; D010802:Phylogeny; D011897:Random Allocation; D012510:Sarcoma 180 / Q000188:drug therapy; D013047:Specific Pathogen-Free Organisms
chemical_list: D062610:Fungal Polysaccharides; D005656:Fungal Proteins