Optimization Of Fermentation And Separation And Preparation For 36-membered Macrolide Azalomycin F

Azalomycin F,as a 36-membered macrolide compounds,have significant anti Gram-positive bacteria,anti-fungal,bacterial resistance to root knot nematode and immunosuppressive activity.Most early,azalomycin F was separated and purified from fermentation liquid of Streptomyces hygroscopicus by Arai,a Japanese scholar.The follow-up study found azalomycin F is composed of three main components of azalomycin F5a,F4a,F3a and several trace analogues.The plane structure of the three main components of azalomycin F was determined by Chandra from Japan in 1995.In 2008,the author Professor Yuan Ganjun separated and purified above three important components of azalomycin F and 9 new analogues from the fermentation liquid of marine actinomycete Streptomyces sp.211726,and the planar structure and the NMR signal has been revised and perfected.More importantly,the three-dimensional structures of 10 compounds of this kind of compounds were determined for the first time in 2012,and meanwhile azalomycin F5a was found to have significantly anti methicillin resistant Staphylococcus aureus(MRSA)activity,which show azalomycin F has a good research value and application prospect in antibacterial drugs(especially drug-resistant bacteria).However,azalomycin F yield is very low,so it is necessary to optimize the fermentation.It is helpful to achieve the content of industrialization after fermentation yield can be improved.To prepare sufficient amount of azalomycin F is to build a solid foundation for the follow-up study about mechanism,further structural modification and structure transformation.This paper investigated 4 kinds of culture medium(medium A,B,C and D)effecting on Streptomyces hygroscopicus(Streptomyces hygroscopicus 13860)for fermentation of azalomycin F,and selected the culture medium C which got the highest yield.Secondly,got the culture medium GR by single factor test of carbon source,nitrogen source,and other ingredients from the culture medium C.Based on GR,we investigated some further the effects of fermentation conditions.Finally,the response surface methodology was used for optimization of fermentation for azalomycin F,and the last to determine for Streptomyces hygroscopicus 13860 to produce azalomycin F the best fermentation medium(g/L):glycerol(25.2),lactose(8),yeast powder(14.7),soybean meal(8),NaCl(5),K2HPO4(2);optimal fermentation conditions:pre fermentation temperature 28℃,the speed of 220r/min,initial pH 6.8;inoculum 10%,fermentation time 9d.At the same time,using various column chromatography,a lot of azalomycin F was prepared,which can provide enough raw materials for the follow-up study.