抗烟草黑胫病菌菌株ZY-19-2的鉴定及发酵条件研究

目的]鉴定抗烟草黑胫病菌的菌株ZY-19-2,并研究该菌株的发酵条件。方法]从烟草根际土样中分离、筛选得到一株对烟草黑胫病菌有抑制作用的菌株ZY-19-2,根据形态特征对其进行了鉴定,并研究了不同培养条件下该菌株产几丁质酶的活力。结果]该菌株为淡紫拟青霉（Paecilomyceslilacinus）;该菌株的最佳发酵条件以1.2%胶体几丁质为碳源,发酵液初始pH值为6.0,以1%蛋白胨为氮源,0.1%吐温80作为表面活性剂,发酵时间为60h,接种量为1%,摇床转速为120r/min,最高酶活达到0.216U/ml。结论]通过对菌株ZY-19-2发酵条件的优化,为应用该菌株规模化生产高效廉价的几丁质酶、几丁质寡糖及对烟草黑胫病防治奠定基础。

Study on Identification and Fermentation Condition of Strain ZY-19-2 with Inhibitory Effect against Tobacco Black Shank (Phytophtora parasitica var. nicotianae Tucker)

Objective] The paper was to identify stain ZY-19-2 with inhibitory effect against tobacco black shank (Phytophtora parasitica var.nicotianae Tucker), and study the fermentation condition of the strain. Method]A strain ZY-19-2 with strong inhibitory effect against P. parasitica were isolated and screened from tobacco rhizosphere soil samples, and identified according to its morphological characteristics. The chitinase production activity of the strain under different culture conditions was also studied. Result] For stain ZY-19-2 Paecilomyces lilacinus, the optimal fermentation conditions were as follows: 1.2% colloidal chitin as carbon source, 1% peptone as nitrogen source, 0.1% Tween 80 as surfactant, initial pH of fermentation broth at 6.0, the fermentation time of 60 h, inoculum amount at 1%, shaker speed at 120 r/min. The highest enzyme activity reached 0.216 U/ml. Conclusion]The optimization of fermentation condition of strain ZY-19-2 lay foundation for large-scale production of cheap and efficient chitinase and chitin oligosaccharides, as well as application of the strain for control of tobacco black shank.