The Relationship Between Mycelial Pellets And The Production Of Endo-β-1,4-glucanase Of Thermoacidophilic Aspergillus Terreus M11 Under Different Submerged Culture Conditions

Under different culture conditions, this paper made an deep research about the morphology of mycelium of Aspergillus terreus M11 and the relationship between the morphology and the amount of enzyme producing. That is, observe the basic morphology of mycelium under different culture conditions, such as inoculum size, initial pH, temperature, speed different carbon and nitrogen sources and etc, and then summarize the relationship between morphology and enzyme production.Through designing different experiments with different carbon and nitrogen sources, temperature, initial pH, shaking rate, inoculum amount, this paper study how the different culture conditions affect the mycelial morphology and the amount of enzyme production. There are three basic shapes of mycelium can be observed, that is:filaments, clumps and spherical, and the size and density are apparent differences in different shapes.Using orthogonal matrix method to optimize the fermentation process, the optimize combination is the temperature of 45℃, initial pH equal to 2, shaking speed of 180rpm, inoculation of 1×106 spores/ml. And then carry fermentation under liquid culture condition, endoglucanase activity reach the highest, while the amount of enzyme production is also greatly enhanced. The characters of Mycelium at this time is that the pellet have diameter of about 1.0-2.0 mm,well-distributed density in the internal structure, no dead hyphae in the middle, reticulate hyphae with appropriate gaps. So it ensure sufficient mycelial biomass in the best state, and mycelial are in good growth condition, which is conducive to the formation of endoglucanase and secretion.The results also show that, even though the culture conditions are different, spherical pellet (diameter 1-2mm) with same size and density has the highest amount of enzyme production. Mycelium morphology directly associated with the fungal enzyme production. Therefore, in the industrial process of enzyme production, observing the mycelium morphology can be used as a key indicator to detect the effects of fermentation.