Abstract:

The regulatory effects of separated added 6-benzylaminopurine and juvenile hormone III before the submerged fermentation of Paecilomyces cicadae on the mycelial growth, intracellular polysaccharide (IPS), cordycepin and adenosine production were explored. The rhythm of mycelial growth and metabolism were different between the control group and the test groups during the whole fermentation process. Two hormones had an promotion effect on the maximum biomass of Paecilomyces cicadae, the biomass of Paecilomyces cicadae was increased by 28.96% and the fermentation time could shorten to 12 h when 6-benzylaminopurine was added at a concentration level of 4 mg/L. In addition, 6-benzylaminopurine and juvenile hormone III could regulate the metabolic rhythm of bioactive materials in Paecilomyces cicadae. The content of IPS was notably increased when 6-benzylaminopurine was added at the low concentration (2 mg/L) (P ＜ 0.05), and juvenile hormone III had an significant inhibitory effect at a concentration level of 4(middle) or 8 mg/L(high) after fermentation for 36 h (P ＜ 0.05). Furthermore, both kinds of hormones also could change the metabolic rhythm of cordycepin and adenosine based on their productivity during the fermentation.

Key words: Paecilomyces cicadae, liquid fermentation, hormone, regulatory effect