抑菌放线菌筛选鉴定及其发酵条件和发酵产物稳定性的研究

Screening and Identification of Actinomycetes and Its Fermentation Conditions and Stability of Fermentation Products

从高黎贡山国家级自然保护区百花岭公园土壤中分离放线菌,以大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌为指示细菌,筛选具有抑菌作用的放线菌菌株,通过培养特征、显微特征和生理生化特征对抑菌菌株进行初步鉴定,并对菌株的发酵条件和发酵产物热稳定性进行研究;从高黎贡山百花岭段土壤中共分离得到放线菌57株,筛选出15株能产生抑菌效果的放线菌,其中F27菌株的抑菌作用最强,抑菌圈直径达16 mm,且对3种指示菌都有抑菌效果,F27菌株的培养特征、显微特征和生理生化特征与孢囊链霉菌属相似度较高,初步鉴定为孢囊链霉菌属;F27菌株的发酵条件为:最佳发酵时间为6 d,发酵培养基的初始pH值7.0,发酵液的培养温度为28℃,最佳发酵培养基为发酵培养基1,装液量50 mL/250 mL,该菌在此条件下抑菌效果更好,抑菌率也比较大。菌株F27的热稳定性、pH耐受性和紫外线照射性都比较差。

Actinomycetes were isolated from the soil of Baihualing Park,Gaoligong Mountain National Nature Reserve.With E.coli,Staphylococcus aureus,Bacillus subtilis as the indicating bacteria,actinomycetes strains were screened.The strains were initially identified by culture characteristics,microcharacteristics and physiological and biochemical characteristics,and the fermentation conditions and thermal stability of fermentation products were studied.57 strains of actinomycetes were isolated from the soil of Galigong Mountain,and 15 strains could produce antibacterial effect were screened,among which F27 strains had the strongest antibacterial effect,with a diameter of 16 mm,and an antibacterial effect on 3 indicating bacteria.The culture characteristics,microcharacteristics,and physiological and biochemical characteristics of F27 strains are highly similar to Streptomyces,and were initially identified as Streptomyces.Fermentation conditions of F27 strain:the optimal fermentation time is 6 d,initial pH value of 7.0,the fermentation medium of 28℃,the best fermentation medium of 1 and the loading volume of 50 mL/250 mL.The strain inhibit better under this condition,and its inhibition rate is relatively large.The thermal stability,ph tolerance and UV irradiation of strain F27 are relatively poor.