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This article aims to antagonistic actinomycetes isolated from Weishanhu lake bottom silt samples screened a broad-spectrum, and its fermentation conditions, the active metabolite preliminary study, the main methods and results are as follows: 1, the experiment 's No. 1 agar medium for separation medium separation to 18 spores heap different colors, different forms of actinomycetes strains point Seeding and screened cylinder plate method one pair fungi and some bacteria have actinomycetes better antagonism, and named actinomycetes 12. Actinomycetes 12 against Staphylococcus aureus, Escherichia coli, Bacillus licheniformis, Trichoderma viride, Penicillium, Aspergillus niger antibacterial experiments, the inhibition zone more than 15mm. 2 actinomycetes colony morphology, cultural characteristics, spore chain morphology, physiological and biochemical experiments, and 16S rDNA sequence analysis method of combining explore actinomycetes 12 species relationship: actinomycetes 12 in Gouraud No. 1 on an agar medium grew better spore heap color to gray, and observed under the microscope: Sporothrix straight or flexing often clustered like, often form long spore chains on the aerial hyphae and therefore can initially Actinomyces bacteria 12 ember gray as Streptomyces taxa; determination and system development by strains 16SrDNA sequence analysis of the study, known actinomycetes 12 highest similarity, 99.7% similarity with Streptomyces rocher preliminary actinomycetes bacteria 12 was identified as a variant of Lou Toru's Streptomyces (Streptomyces rocher), there are differences between some of the physiological and biochemical characteristics. Using single factor experiment Plackett-Burman (PB) experimental design and orthogonal design method of combining actinomycetes 12 production of active substances to optimize the fermentation conditions to obtain optimal culture conditions and the level of: seed liquid incubation time 17h, inoculated 2mL seed liquid to 50ml/300mL the medium, fermentation 72h, wherein the optimal medium for: bean powder concentration of 1.25%, glucose 1%, ammonium chloride 0.35%, sodium chloride 0.6%, sulfuric acid magnesium 0.2%, calcium carbonate 0.25%, and the initial pH was 6.4, the stability of the active substance in 12 fermentation broth actinomycetes done research results show that: the fermentation broth by pH of the actinomycetes 12 respectively 2,4 antibacterial activity of active substances in the, 6,8,10,12 solution treatment almost unchanged; fermentation was placed under UV light irradiation 20min, 40min, 1h, 2h, 3h, 4h, 5h, 6h, active substances inhibitory activity was almost unchanged; fermentation broth by high temperature treatment, the temperature is below 80 ° C, the antibacterial activity of almost constant, 100 ℃ for 1h antibacterial activity slightly weakened, 121 ℃ 20min, still has antibacterial activity, generally speaking, the better the stability of the active substance in the fermentation broth. 5, using the active substance in the organic solvent extraction of the fermentation broth, low The results show that the distribution ratio of the active substance in the organic solvent, ethyl acetate, chloroform, and the active material can not be petroleum ether, n-butanol and benzene extraction, may be a highly polar antibiotics; use the Czech eight solvent system to the active substance Fair layer analysis, the results of the active substance in the fifth kind of solvent system and the six kinds of the solvent system to the Rf value is larger, while in other systems the Rf value smaller or 0 Rf value connection to the sail-shaped, with streptomycin, kanamycin, Jinggangmycin Similar infer that the active substance may belong to the alkaline water-soluble antibiotic substances.
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