Identification of Anamorph Yeast of Tremella aurantialba and Optimization of Medium Composition for Production of Exopolysaccharides  

作　　者：刘春卉 杨秀伟 俞建国 马维新 瞿伟菁 包艳洁 武文斌 庄秀园 

机构地区：[1]China National Institute of Standardization,Beijing 100088,China [2]Dept.Natural Medicines,State Key Lab.Natural and Biomimetic Drugs,Sch.Pharm.Sci.,Peking Univ.,Beijing 100191,China [3]Jiangsu Tongyuantang Bio-engineering Co.,Ltd.,Taixing,Jiangsu 225400,China [4]School of Life Science,East China Normal University,Shanghai 200062,China

出　　处：《过程工程学报》2012年第6期973-981,共9页The Chinese Journal of Process Engineering

基　　金：Supported by the Key Project of National 9th Five-Year Plan Program (No.96-C02-03-06)

摘　　要：A yeast-like fungus strain B1 isolated from wild fungus Tremella aurantialba was identified and initially characterized. Two phylogenetic trees were generated based on the sequences of large subunit ribosomal RNA gene D1/D2 regions and internal transcribed spacer (ITS) regions of related fungi, respectively. The analysis of D1/D2 regions and ITS sequences showed that fungus B1 was clustered together with T. aurantialba, T. aurantia and T. microspore in the phylogenetic trees. Both the morphological characteristic and phylogenetic analysis established that fungus B1 was one of the anamorph strains of T. aurantialba and belongs to Tremella genus. A fermentation medium for exopolysaccharides (EPS) production by T. aurantialba B1 . Plackett-Burmen design was used to evaluate the effects of different components in the culture medium. Glucose and yeast extract have significant influence on the EPS production. The concentrations of two factors were optimized subsequently using central composite design and response surface analysis. The results showed that 49.2 g/L glucose and 10.4 g/L yeast extract could lead to the maximum production of EPS (4.99 g/L). The optimized medium led to a 1.5-fold enhancement of the production of EPS by T. aurantialba B1 , as compared with that without optimization.A yeast-like fimgus strain B1 isolated from wild fungus Tremella aurantialba was identified and initially characterized. Two phylogenetic trees were generated based on the sequences of large subunit ribosomal RNA gene D1/D2 regions and internal transcribed spacer （ITS） regions of related fungi, respectively. The analysis of D1/D2 regions and ITS sequences showed that fungus B1 was clustered together with T. aurantialba, T. aurantia and T. microspore in the phylogenetic trees. Both the morphological characteristic and phylogenetic analysis established that fi.mgus B1 was one of the anamorph strains of T. aurantialba and belongs to Tremella genus. A fermentation medium for exopolysaccharides （EPS） production by T. aurantialba B1. Plackett-Burmen design was used to evaluate the effects of different components in the culture medium. Glucose and yeast extract have significant influence on the EPS production. The concentrations of two factors were optimized subsequently using central composite design and response surface analysis. The results showed that 49.2 g/L glucose and 10.4 g/L yeast extract could lead to the maximum production of EPS （4.99 g/L）. The optimized medium led to a 1.5-fold enhancement of the production of EPS by T. aurantialba BI, as compared with that without optimization.

关 键 词：Tremella aurantialba anamorph yeast large subunit ribosomal RNA gene internal transcribed spacer EXOPOLYSACCHARIDES central composite design 

分 类 号：Q939.97[生物学—微生物学]