Identification Of Streptomyces Sp. F-1013 And Analysis Of Its Physiological Activities

The morphological, cultural, physiological and biochemical characteristics of the strain Streptomyces F-1013 which was isolated from the shell of shrimp were analyzed, the result indicated that the aerial hyphae of Streptomyces F-1013 presented spiral form, the spore was round or ellipse and its surface was smooth; the substrate mycelia was straight and had many divarication. The strain F-1013 grew bloom on Czapek's medium, PSA, soybean medium and S medium, grew generally on CMA and feebly on glycerol arginine agar medium. Streptomyces F-1013 could utilize cellulose, hydrolyze of starch, coagulate and peptonize milk and produce H₂S etc, but could not produce pigments by making use of tyrosine. Streptomyces F-1013 could utilize α-Lactose, maltose, D-fructose, L-inositol, D-xylose, Glycerol, D-mannitol and Glucose, but could not utilize sucrose and sodium. All these characteristics were very similar to those of Streptomyces roseoflavus Arai,1951. In addition, 16S rDNA sequence indicated that Streptomyces F-1013 and Streptomyces roseoflavus has the identity of 99.93% and of 100% between the 120bp-γ regions of 16S rDNA of the two strains. Accordingly, Streptomyces F-1013 identified as Streptomyces roseoflavus F-1013.Contrasting with other fermentation liquor, by adjusting pH8-9 and fermenting 5-7 days, the shrimp fermentation liquor was the best of all in the ability of producing germ and chitosan, the soluble chitosan concentration could reach 0.3mg/mL. The experiment of antagonistic effect against plant pathogenic fungi indicated that shrimp fermentation of Streptomyces roseoflavus F-1013 had distinct antagonistic effect against plant pathogenic fungi such as Colletotrichum sp., Rhizoctonia solani, Fusarium oxysporum f.sp.. The antagonistic rate could reach 100%, 96.3% and 94.7%...