Protoplast formation and regeneration of the itaconic acid producing strain aspergillus terreus T-730

The strain Aspergillus terreus T-730,an itaconic acid producer,was used to prepare protoplasts. The effects of some factors such as culture method,enzyme systems, mycelium age,digesting time and temperature, regemeration methods on its formation and regeneration were studied.The results indicated that the optimum condition for preparing protoplasts was:The spores cultured in liquid terreus T-730 medium for 12h～14h ,then the obtained myceliums were treated with mixed enzyme which including 0.6%cellulase, 0.3%Snailase and 0.1%Lysozyme in 35℃ for 3.5h. Then high yield of protoplasts was obtained, and the regeneration frequency was 70.6% cultured with double layer medium in 32℃.