The Isolation, Identification Of Probiotics BL-Y-1 From Fowls And Studies On Their Biological Traits, Fermented Condition And Initial Application

The series consequences of antibioties bause cause panic in the socicty. To find a safty and nontoxic replacer is imperative.Probiotics is just the good choice.Atfer many yeaes practice and researeh, Bacillus spp.is benefit to the growth and development of animals. Bacillus sp.can not only inhibit the growth of pathogenic bacteria, also produce nutritious substances, and is of the most potential sources of probiotics.The study of viable organism has been developed greatly these 20 years.But the elaboration, use, conservation and transportation of viable organism will make bioactivity down.Meanwhile, some strains cannot counteract HCl, bile salt etc.when they go through the circumstance of low pH in stomach.So they cannot arrive intestinal tract and produce a marked effect.Therefore, the exploitation of strains which are of the capacities of anti-high temperature, anti-low pH, anti-bile salt and nice adhesion action is the most important task to do.The ideal strains should be from same kind of animals intestinal tract. The study isolated and identificated the probiotics which adhered to the intestinal tract of healthy egg chicken on the base of the theory.The safe, antibiosis and anti-pepsin etc.were researched.At the same time, the better strains were initially applied. BacillusY-1 was successfully isolated and selected from healthy poultry cecum and colon as probiotic candidates.against ginger bacterial wilt caused by Coliform. It psmorphological, cultural physiological, biochemical characteristics and 16S rDNA sequences analysis were studied. A phylogenetic tree was constructed by comparing with the published 16SrDNA sequences of the related bacteria species. In the phylogenetic tree the overall similarity value between strain Y-1 and 11 type Pantea are 94.63 %～99.35 %, Y-1 is identified by Brevibacillus laterosporus. Using bile salt medium, the tolerance of Bacillus was studied in the simulated natural(bile salt content 0.3% environment.Then the survival rates of bacteria after incubation in artificial gastric juice and intestinal environment for different time were detected.Those having strong tolerance were preliminarily regarded as probiotics. The experimental results show that the Y-1 in bile salt, artificial gastric and intestinal juice that demonstrated strong tolerance.In order to increase the quantity of antifungal protein from Brevibacillus laterosporus Y-1, the strain was cultured under different conditions.The carbon source, nitrogen source and inorganic salts of the fermentation cultrue medium were screened.The results displayed that the proper components were sucrose, tryptone and K2HPO4, CaCl2 and MgSO4.By orthogonal design, the optimal proportions of fermentation medium were glucose 20 g·L-1, tryptone 5 g·L-1, KH2PO4 2 g·L-1, CaCl2 0.25g·L-1, MgSO4 0.5 g·L-1.Several technical and engineering parameters during the shake flask fermentation of antifungal proteins studied by means of the orthogonal experiment design.The optimum shaking flask fermentation condition were proper inoculation 8%, at 180 r/min for 16 h under 35℃.Under the conditions, the most quantity of antifungal protein was obtained. After optimization, OD increased 1.1.This study including an experiment was conducted to evaluate the effeets of dietary Bacilli probioties on permance in Avian broilers of l～28 days old, and to assess the roles of dietary bacillus.The study aims to serve as the base for further researeh and application on bacillus as feedstuff additive.Several strains of probiotics were isolated successfully,which not only can sovle the concordance of the origins of probiotics and application object, but also strengthen the specificity of the effect of probiotics and quality and safety of the product of probiotics.Meanwhile,isolation of new probiotics is profit to the extensive application in the realm of cultivation and diseases prevention.For the animal microecology preparation, not only the cost should be thought, but also the economic value etc.In the experiment fresh bacteria feed was actively attemted.The researcher hoped that fresh bacteria preparation can be changed into a kind of simple,economic, practical and easy-spreading technique, which can be applied to practice.The association application of probiotics did lots of work for the anti-infection compound probiotics preparation.