Method for promoting microbes to synthesize ascomycin by using exogenous additive and preparation of seed liquor and culture medium

Abstract

The invention discloses a method for promoting microbes to synthesize ascomycin by using an exogenous additive and a preparation of a culture medium, and belongs to the technical field of biologic synthesis of ascomycins. The method is characterized in that, on the basis of the characteristic that the ascomycin biologic synthesis process refers to the assembly of various precursors, at the beginning of the aerobic fermentation or in the process of aerobic fermentation, 0.5-3.0 g of shikimic acid, 0.5-3.0 g of isoleucine and 1-5 g of soybean oil are added in every one liter of a culture mediumfor enhancing the accumulation of ascomycin synthesis precursors DHCHC, malonyl and methyl malonyl, promoting the metabolism of the ascomycin synthesis pathway, thereby improving the yield of the ascomycin. The method provided by the invention is simple to operate and is low in cost because no extra device and labor is increased and only low additional investment is input; in the step of fermenting and culturing streptomyces hygroscopicus ascomycota subspecies, the fermenting unit of the ascomycin is improved by 55.9-114.7% as compared with a control group.

Description

technical field

[0001] The invention belongs to the technical field of microbial fermentation, and in particular relates to a method for exogenous additives to promote the synthesis of ascomycin by microorganisms and the preparation of culture medium. Background technique

[0002] Ascomycin (FK-520) is a macrolide antibiotic composed of a twenty-three-membered ring produced by the fermentation of Streptomyces hygroscopicus var.ascomyceticus. Its chemical name is 17α-ethyl-1β, 14α-dihydroxy-12β[2-(4α-hydroxy-3β-methoxy-1β-1-(E)-methylvinyl)]-23α, 25β- Dimethoxy-13α, 19, 21α, 27β-tetramethyl-11,28-dioxa-4-azatricyclo[22,3,1,O]octadecano-18-2,3 , 10,16-tetraketone, monohydrate. Relative molecular mass is 822.5, molecular formula C 44 h 69 NO 12 ·H 2 O. Soluble in methanol, ethanol, acetone, ethyl acetate, ether, benzene, soluble in tert-butyl methyl ether, slightly soluble in water, cyclohexane, n-hexane, insoluble in heptane.

[0003] Ascomycin is an ethyl analog of ta...