Marine Antinomycete Strain M058 Biosynthetic Condition And Extraction Method Of Antibiotic

Antimicrobial activity of marine antinomycetes M023,M056,M058,M066,M220,M230 strains were studied by method of double layers agar and the results showed some strains had an antimicrobial activities. Strain M058 had strong activity against Staphylococcus aureus(Gram-positive bacteria) and Pseudomonas, also had activity against Escherichia coli(Gram-negative bacteria) and Candida albicans(fugal), and had low activity against Pseudomonas aeruginosa , Marine antinomycete M058 was a strain of yielding broad-spectrum antibiotic, so strain M058 was studied further.The morphology of mycelium and spores in Gause's syntetic No1 media, growth situation and physiol-biochemical characteristics in different media were observed. According to Identification Manual of Streptomyces, strain M058 was identified to be Aureus group of genus Streptomyces, and similar to Streptomyces aureus.For increasing production of antibiotic, the liquid media composition were studied. Antibiotic content of the fermented liquid was determined by cylinde-plate method, the screening result indicated that the optimal carbon source was soluble starch, and the optimal nitrogen source was KNO3. By changing the ratio of carbon source and nitrogen source , and orthogonal tests of carbon, nitrogen and phosphate , the optimal proportion of these component was obtained and percentage of these component was soluble starch 1%, KNO3 0.15%, K2HPO4 0.075%.The suitable technical parameters in fermentation were: initial pH 7.0~7.5, 25℃, 10% inoculum, loading liquid volume 50 ml(in 250ml flask). On the conditions of the optimal media and the suitable fermentation condition, the antibiotic yield of strain M058 reached maximum in 36~48 hours. Fermentation process of strain M058 in 20L fermenter was designed to yield more antibiotic for further study, and fermented liquid was determined by cylinde-plate method ,and stopped fermenting when the antibiotic yield of strain M058 reached maximum.The fermented liquid was filtrated, the filtrate was concentrated. The concentrated product was extracted by ethyl acetate, then the concentrated product was adsorbed by active carbon, and the active carbon was eluted by acetone solution. Oil-soluble antibiotic A and water-soluble antibiotic B were gained. Both oil-soluble antibiotic A and water-soluble antibiotic B had activity against Staphylococcus aureus. Components of A and B were determined by silica GF254( HPTLC). Components of A and B were purified primarily by 200~300 sizes silica. Method of purifying oil-soluble antibiotic A and water-soluble antibiotic B were studied primarily. Part physico-chemical properties of A and B were found, which were bases for purifying of A and B further.