【摘要】 对海洋真菌Xylaria sp.(No.2508)生产xyloketal B的摇瓶发酵过程进行了初步优化。结果表明,Xylaria sp.(No.2508)在培养120h时xyloketal B产量最高,当培养168 h后菌体进入衰亡期且xyloketal B迅速降解,因此Xylaria sp.(No.2508)生产xyloketal B的最适发酵周期为120h;Xylaria sp.(No.2508)合成xyloketal B的过程及用乙酸乙酯萃取xyloketal B的过程对pH非常敏感,其中最适xyloketal B生产的发酵液初始pH为5.7,利用乙酸乙酯萃取xyloketal B时的发酵液最适pH为3.0;最适接种量为10%(υ/υ);接种前发酵液中加入10g/L的大孔树脂XAD-16可以降低某些代谢产物对xyloketal B合成的抑制作用,从而使产量提高2倍左右,而菌体进入稳定期以后加入大孔树脂XAD-16对产物产量没有影响。更多还原

【Abstract】 The fermentation optimization of xyloketal B produced by marine fungus Xylaria sp.(No.2508 ) was preliminarily investigated in shake flask.The results showed that the production of xyloketal B was the highest at 120 h after inoculation.Xylaria sp.(No.2508) reached decline phase at 168 h and at that time the xyloketal B was degraded rapidly.Therefore the optimal fermentation cycle for producing xyloketal B by Xylaria sp.(No.2508) was 120 h.It was found that both the biosynthesis and extraction by ethyl acetate for xyloketal B was sensitive to pH.The best initial pH of production culture was 5.7 while the optimal pH of the culture before extraction was 3.0.The optimal inoculum concentration was 10%(v/v).Meanwhile it was found that the addition of 10 g/L XAD-16 macroporous resin before inoculation could reduce the inhibition of producing xyloketal B by the metabolic products of Xylaria sp.(No.2508) and increase the production of xyloketal B by 2 times.However the addition of XAD-16 macroporous resin in the stationary phase had no effect on the production of xyloketal B.更多还原