Study on the improvement effect of low- frequency ultrasonic on the production of α- dextranase in Chaetomium gracile

Low- frequency ultrasonic technique was employed to resolve self- flocculation that restrained the production of α- dextranase in Chaetomium gracile,and cell growth and enzyme activity were also evaluated under variable low- frequency ultrasonic action time and frequency by experiments. The results indicated that a visible improvement in self- flocculation of Chaetomium gracile under treatment of 20 s /20 min,20k Hz and 300 W,accompanied with an 87.9% increased α- dextranase enzyme activity,from 102.9U / m L to 193.4U / m L. The results showed that low- frequency ultrasonic was beneficial to improve physiological activity and efficiency in the production of α- dextranase in Chaetomium gracile.