马勃状硬皮马勃产胞外多糖发酵条件优化

Optimization for Fermentation Conditions of Exopolysaccharides Production by Scleroderma areolatum Ehrenb

在单因素试验的基础上,采用正交试验优化了马勃状硬皮马勃产胞外多糖(EPS)的摇瓶培养条件,并研究了马勃状硬皮马勃的形态学和黏度特征。单因素试验结果表明,马勃状硬皮马勃产EPS的最适生长周期为10 d,最佳碳源、氮源、无机盐分别为果糖、大豆粉、Mg SO4与KH2PO4,最适环境条件为温度26℃、p H值8.0。在此基础上,选用碳源、氮源和无机盐3个因素,应用正交试验优化的马勃状硬皮马勃产EPS的最佳培养基配方为:20 g/L果糖、5 g/L大豆粉、2.5 mmol/L KH2PO4、2.5 mmol/L Mg SO4,在优化培养条件下,EPS产量为2.627 g/L。优化培养条件下的形态学和黏度研究表明,马勃状硬皮马勃的菌丝体呈分枝状生长,黏度与培养时间呈正相关,p H值与培养时间呈负相关。研究结果对马勃状硬皮马勃真菌EPS产品的大规模生产和开发具有一定的意义。

Based on the results of single-factor experiments,orthogonal test was adopted to optimize the culture conditions in shake flasks for exopolysaccharide（ EPS） production by Scleroderma areolatum Ehrenb.Moreover,the morphological and viscosity characteristics of the fungus were also investigated. The results of single-factor experiment showed that the most suitable growth period was 10 d; the best carbon source,nitrogen source and inorganic salts were fructose,soybean powder,Mg SO4 and KH2PO4,respectively; the optimal temperature and p H value were 26 ℃ and 8. 0,respectively. Based on the above results,three factors,including carbon source,nitrogen source and inorganic salts were selected and optimized by the orthogonal test for EPS production,and the optimal medium was： 20 g / L fructose,5 g / L soybean powder,2. 5 mmol / L KH2PO4 and 2. 5 mmol / L Mg SO4. Under the optimal culture conditions,the EPS yield was2. 627 g / L. The morphology and viscosity of S. areolatum under the optimal culture conditions showed that the mycelia was branched,the viscosity was positively related with culture time,the p H value was negatively associated with the culture time. The results will be helpful for the scaled-up production and exploitation of fungal EPS products from S. areolatum.