低强度超声波刺激对阿氏假囊酵母细胞次生代谢的影响

一定强度的超声波能够促进细胞的生长和代谢，细胞膜是抑制微生物次生代谢产物产量的主要原因。以阿氏假囊酵母(E．ashbyii)为实验材料，选择功率6W、频率24kHz的超声加载于摇瓶发酵过程中，检测了加载对菌丝体干重和核黄素分泌的变化情况。结果表明，一定强度的超声间断加载对E．ashbyii的生长有一定的促进作用，并使核黄素的开始分泌时间从96h缩短到60h；同时发现，发酵96h后加载，能有效提高核黄素的产量至0．346mg／L，非常显地高于对照组；发酵后的104～112h是超声处理的最佳时间段，为维持较高的产率，需每隔1．5h再次超声处理。

Effect of Low Intensity Ultrasonic Stimulation on Secondary Metabolite of Ecemothecium ashbyii

Some intensity ultrasonic can accelerate cell growth and metabolize. The structure of the cell membrane is considered to be one of the main obstacles in the improvement of riboflavin productivity, which impedes the release of riboflavin from the cell into the fermentation broth. Ecemothecium ashbyii was studied in this paper, and 6 W, 24 kHz of ultrasonic was loaded during fermentation. In order to investigate the effect of ultrasonic on biosynthesis of riboflavin in medium of E.ashbyii, dry weight of mycelium and content of riboflavin were measured. The results of the present study showed that the beginning time of riboflavin secretion into medium was shortened from 96 h to 60 h, through stimulating during fermentation. The content of riboflavin was most obviously enhanced to 0.346 mg/L, as compared with the control and the total riboflavin quantity increased by ultrasonic treatment. The optimal stimulation time was from 104 to 112 h and ultrasonic should be loaded every 1.5 h.