Enhanced strategies for lovastatin production by Aspergillus terreus

• Main Authors: Tsung-Yao Cheng, 鄭宗堯
• Other Authors: Long-Shan Lai
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/6a83ew

碩士 === 朝陽科技大學 === 應用化學系碩士班 === 93 === Using a 5 l fermentor at 28oC, the dissolved O2 (DO) supplement of 0-48 h dominated pellet formation of Aspergillus terreus, which substantially increased the synthesis of lovastatin. Coupled with the DO comparatively controlled at 20%, a simple temperature-shift (28-23oC at day 4) was proved valuable, where the maximum of lovastatin production was enhanced by 20% in comparison with that at 28oC. Nevertheless, the product enhancement was only accompanied with a 6% reduction in biomass production. It was found that the temperature-shift method used here significantly increased the DO, closely altered the physiological states (such as the pH kinetics, sugar utilization etc.), probably thus resulting in the enhancement of product formation. However, using a 5 l fermentor operated at 200 rpm, this same temperature-shift contradictorily gave a slightly negative effect on product formation although the DO in broth was raised up in later stages of the fungal fermentation. According to the results of such experiments, we concluded that the disparity in product formation was mainly attributed to the difference of DO supplies in earlier growth stage of the fungus.