Study on Extracellular Enzyme Activity from Dictyophora echino-volvata Zane during Submerged Fermentation

Bacterial strain of Dictyophora echino-volvata Zane was used as test material,the activity variation of six extracellular enzymes from Dictyophora echino-volvata Zane during submerged fermentation was studied,by the methods of liquid culture,and the biomass of mycelium were determined.The results showed that the enzyme activity was closely related with the mycelium biomass.Increase in mycelum biomass was of 'S' curve,and the fastest growth of the mycelium occurred at earlier developmental stage,especially the first 4～6 days.The biomass of mycelium reaches its maximum after the enzyme activity peak of carboxymethyl cellulose enzyme and amylase,whereas the activity of other four enzymes increased simultaneously with that of the mycelial biomass of D.echino-volvata.Zana These findings demonstrated that the mycelium deomposed starch and cellulose first during fermentation,then lignin and protein were used as their C and N sources.To promote the fermentation efficiency and the reduction of culture period,sufficient C and N sources will be provided before the maximum biomass of mycelium came out.To achieve the maximum mycelium biomass,nutrition allocation and fermentation cycle of the mycelium should be considered based on the activity peak time of different enzymes.