茶薪菇产纤维素酶最佳液体发酵条件的研究

Study on the Optimum Liquid Fermentation Conditions for Producing Cellulase by Agrocybe chaxingu

[目的]研究茶薪菇产纤维素酶的最佳液体培养条件。[方法]以茶薪菇为材料,探讨碳源、氮源、初始pH值、温度、转速和培养时间对茶薪菇产纤维素酶的影响,确定最佳发酵条件。[结果]麸皮为碳源时,茶薪菇产纤维素酶活力最高,葡萄糖为碳源时产酶活力较低。(NH4)2SO4为氮源时,茶薪菇产纤维素酶活力最高,其次是酵母粉与蛋白胨。茶薪菇在pH值6.0时产酶活力最高。28℃以下时茶薪菇生长较缓慢,32℃以上时菌丝生长较快,但酶活力较低,30℃时产酶活力最高。转速180 r/min、培养时间5 d时茶薪菇产酶活力最高。[结论]茶薪菇产纤维素酶的最佳液体培养条件为麸皮5%,(NH4)2SO41%,初始pH值6.0,培养温度30℃,转速180 r/min,培养时间5 d,此条件下,纤维素酶活力达40.2 U/ml。

[Objective] The research aimed to study the optimum liquid culture conditions for producing cellulose by Agrocybe chaxingu. [Method] With A. chaxingu as materials, the effects of carbon source, nitrogen source, the initial pH value, temperature, the rotational speed and culture time on producing cellulose by A. chaxingu were discussed to confirm the optimum fermentation conditions. [Result] When carbon source was bran, the activity of cellulose produced by A. chaxingu was highest. While the activity of producing cellulose was lower when carbon source was glucose. When nitrogen source was （NH4）2SO4, the activity of cellulose produced by A. chaxingu was highest, followed by yeast powder and peptone. The activity of cellulose produced by A. chaxingu was highest at pH value of 6.0. When the temperature was below 28 ℃ ,A. chaxingu grew slowly. When the temperature was above 32℃,A. chaxingu grew faster and the enzyme activity was lower.The activity of producing cellulose was highest at 30℃ .When the rotational speed was 180 r/min and culture time was 5 d, the activity of cellulose produced by A. chaxingu was highest, [ Conelusion]The optimum liquid culture conditions for producing cellulose by A, chaxingu were as follows： 5% bran as carbon source,1% （NH4）2SO4 as nitrogen source,the initial pH of6.0,the culture temperature of 30 ℃ ,the rotational speed of 180 r/min,the culture time of 5 d,under which,the cellulose activity reached 40.2 U/ml,