雪白弯颈霉C41发酵液稳定性及粗提物的抑菌活性

Stability of Fermentation and Antimicrobial Activity of Crude Exact of Tolypocladium inflatum C41

[目的]研究雪白弯颈霉C41菌株固体发酵粗提物的抑菌活性及其发酵液在不同条件下的稳定性。[方法]采用菌丝生长速率法,以7种植物病原真菌为供试菌,测定雪白弯颈霉C41固体发酵粗提物的抑菌活性;以玉米弯孢菌叶病菌为指示菌,测定发酵液在不同条件下的稳定性。[结果]固体发酵粗提物对玉米灰斑病、玉米弯孢菌叶斑病和玉米大斑病病菌菌丝生长均具有较强的抑制作用,抑制率分别为90%、84.38%和80%。发酵液在25~60℃范围内有较好的热稳定性,温度高于60℃则稳定性降低;有较广泛的酸碱稳定性,在pH值为6时抑菌活性最好;发酵液对日光和紫外线的稳定性较强。[结论]雪白弯颈霉C41菌株的代谢产物具有广谱的抑菌活性和较好的稳定性。

[Aims] The aims were to study the antimicrobial activity of the crude extract of Tolypocladium inflatum and the stability of the fermentation in different conditions. [Methods] The antibacterial activity of the crude extract of solid fermentation was determined by using the mycelial growth rate method. Seven plant pathogens were used as detected fungi to determine stability of the fermentation broth by the growth rate method. The stability of the fermentation broth under different conditions was determined by Curvularia lunata. [Results] Antimicrobial tests showed that the crude extracts had strong inhibitory effects on the growth of Cercospora zeae-maydis, Curvularia lunata, and Exserohilum turcicum with the inhibitory rate of 90, 84.38 and 80%, respectively. Stability tests showed that the stability of the fermentation broth in the temperature range of 25-60 ℃ has better thermal stability, and the stability is lower than 60 ℃.The stability of the fermentation broth is better at pH 6. The crude extract also had a high stability when exposed to sun light and ultraviolet light. [Conclusions] The crude extract of Tolypocladium inflatum C41 has a broad spectrum of antimicrobial activity and good stability of fermentation broth.