Fermentation Process Optimization,Separation And Structure Analysis Of Compound SIPI-Z3 From Microorganisms

With the pre vale nce of drug-resistant bacteria,it is still one of the ways to find new active compounds from microbia l metabolites.A strain of actinomycetes was preserved in the laboratory,and its fermentation broth had obvious activity aga inst Gram-positive bacteria.In order to study the components with antibacterial activity,the following studies were carried out on this strain:1.Through dilution separation and antibacteria l activity screening,a strain w ith high antibacteria l activity was obtained from glycerine tube and was named as fxj-01 using the starting strain.2.A high content compone nt named as SIPI-Z3 was found in the metabolite of fxj-01 by HPLC.The optimum fermentation medium was obtaine d by optimizing the fermentation process of strain fxj-01,whic h was 2%lactose concentration,5%soluble starch,2%beef extract,2%yeast extract,0.06%potassium dihydrogen phosphate,0.015%anhydrous magnesium sulfate;based on the best composition of the fermentation medium,the optima l fermentation conditions were obtained:p H 6.2,seed age 2 days,inoc ulation amount 6%,conta ining 50 ml in 250 ml flask,the fermentation temperature 32℃,the rotation speed 250r/min,the fermentation period 6 days,and0.4%yeast powder added every other da y.The fermentation le vel of SIPI-Z3 was 124%higher than that of the starting process under the optimal fermentation medium and conditions.3.SIPI-Z3 compound samples were isolated from the fermentation broth by UV absorption tracking,cation exchange resin extraction,macroporous adsorption resin separation and purification,decolorization and other technica l methods.The purity of SIPI-Z3 compound was 95%and the yield was 85%by HPLC analysis.4.Through the determination of LC-MS and NMR data,combined with literature research and data ana lysis,it was found that the molecular we ight of the compound was204,the molecular formula was C₁₁H₁₂N₂O₂,its carbon and hydrogen spectrum data were basically consistent with tryptopha n,and the structure of SIPI-Z3 compound was consistent with tryptophan.5.By using the traditiona l taxonomic method,comparing the characteristics of colony and mycelium morphology,physiologica l and bioche mical characteristics with 16S rDNA sequencing,it was preliminarily determined that the fungus was k ibdelosporangium aridum.Tryptophan compound is isolated from k ibdelosporangium aridum for the first time in this study.