球孢白僵菌液体生长营养和培养条件优化

摘要

The principal objectives of this study were to determine the optimal liquid culture conditions in shake flasks for maximal biomass and blast spores of Beauveria bassiana. The results showed that glucose was the suitable carbon source,and yeast powder was the suitable nitrogen source for the growth of strain DZDC-9. Adding 0.000 5 mol/L KCl into the submerged culture can significantly enhance the yield of biomass and blast spores. The biomass reached(13.184±0.328 6)g/L after 60 h. The best culture conditions were shake flasks with one-fifth nutrient so-lution and initial conidial concentration of 107 spores/mL in a rotary shaking incubator at 200 r/min at 26 ℃ , which could increase the biomass and shorten the incubation time. Using the selected nutrition and culture condi-tions to produce conidia,the yield could achieve 22.30±1.78 per kilogram of rice.%以菌株液体发酵过程中菌丝干重和芽生孢子浓度为测试指标，对球孢白僵菌DZDC-9菌株液体发酵营养需求进行优化，结果表明，菌株生长的适宜碳源为葡萄糖，适宜氮源为酵母粉，在基础培养液中添加0．0005 mol／L KCl可以显著提高菌丝和芽生孢子浓度。通过单因素分析和正交设计对不同培养条件下菌丝生长量进行测定，结果表明，在培养温度26℃，培养液装样量1／5，初始接菌量107个／mL，转速200 r／min的培养条件下，菌株液体发酵能在60 h达到最大菌丝生长量（13．184±0．3286）g／L。利用筛选出的培养基和培养条件进行液固双相发酵试验，得到的孢子粉产量为（22．30±1．78）g／kg大米，显著高于优化之前的产量（13．04±1．90）g／kg大米。