Study On Actinomycetes Resource Of Anti-Animal Pathogrens From Salin Soil In Shaanxi And Ningxia

In this experiment, the actinomycetes were isolated from the saline-soil in Shaanxi andNingxia regions as tested actinomycetes,9kinds of animal enteric pathogens as target bacteria.The aim is to get some of the excellent antagonistic actinomycetes and doing a preliminaryexploration actinomycetes in these region. This can lay the foundation for future developmentand utilization.1172actinomycetes were researched using agar plate method and the flat aperturemethod, obtained the antinomycetes group composition, antimicrobial spectrum law andgood antagonist in this region. On several strains with fine antagonistic actinomycetefermentation liquid nature and the composition were studied. We made68H02mediumoptimization and fermentation medium choice experiments. The main conclusions are asfollws.1. Streptomyces was the main sort in these areas, accounting for89.82%of the testedstrains. Non-Streptomyces accounted for11.18%of the total number of actinomycetes. And71.76%of the Streptomyces belonged to Albosporus, Griseo rubroviolaceus, Flavus, Cinereus,Globosporus. About47.1%actinomycetes had antagonist activity. The broad spectrum ofAntagonistic Actinomycetes was less. The tested actinomycetes had different functions ofdifferent target bacteria. Antagonistic effect was best on Staphyloccocus aureus I and bovineStreptococcus agalactiae II.2. According to the morphological characteristics, phusiological and biochemical results,and molecular biology identification, initially identified30tested strains were Streptomyces.5excellent antagonistic actinomycetes molecular identification results were showed that strain68H02was similar to Streptomyces xinghaiensis, while strain69A11to Streptomyces rubrus.strains71H10, SWN323and SWN342in turn were of Streptomyces staurosporininus,Streptomyces xinghaiensis and Streptomyces coeruleofuscus.3. The antibacterial activity for several strains remained unchanged while fermentationbtoth temperature, pH cinditions and storage stability test of time, indicating that thefermentation liquid had good stability on storage time, temperature and pH.4. Orthogonal test method was used for medium optimization in this chapter. The results showed that fermentation process optimization in the seed age of36h, inoculum size6%,initial pH of8.5, cultured132h, the titer of the strain can reach the maximum value. Thepotency of the fermentation broth can reach192.45μg/ml,5.34times higher than before. Onthis basis, fermentation medium screening results showed that soybean powder was mostconducive to the strains of fermentation.