Optimization In Preparation And Animal Test Of Antimicrobial Peptides Feed Additive

Since the issues such as drug residues and abuse of antibiotics have bccome increasingly prominent in modern society,the feed additive research and development of new types of security have become the current hot spots of universal concern. Small molecule proteins or peptide materials (antimicrobial peptides) which were considered to be a natural biological preservatives and antibiotics substitute synthesized by microbial metabolism had the ability to inhibit or kill a variety of pathogens and spoilage organisms, as well as had properties of a safe, non-toxic and efficient. It has broad application prospects in food and animal husbandry.This experiment was designed to prepare antimicrobial peptides feed additive with antimicrobial peptides produced by B. Laterosporus S62-9; produce and optimize antibacterial peptides feed additive preparation conditions; research stability of Antimicrobial Peptides Feed Additive with antimicrobial peptides produced by B. Laterosporus S62-9. The study also had a purpose of the bacteriostatic test in the meat chicken and laying hens in vivo and researched the impact on production performance in chicken. Meanwhile it is prepared that Antibacterial peptides in probiotics with further step and optimize the preparation conditions.After antimicrobial peptides feed was optimized in the experiment, the adsorption conditions were:solid-liquid ratio of 6.5%(m/v), the adsorption temperature 45℃, the adsorption time 25 min, so that adsorption rate of the antimicrobial peptide feed additive preparation process and unit titer of antimicrobial peptides feed additives have been improved.The antimicrobial peptide feed additives has strong stability and the loss of antibacterial activity is very small in the condition of 4℃ refrigerated 60 days and 100℃ for 60 min, and the difference between test group and the control group in the inhibition zone diameter only 2.10-7.01 mm by pH 4-8, with a smaller loss of antibacterial potency. Antimicrobial peptides feed additives to reduce the rate of inhibition zone diameter treated with pepsin, lipase and catalase were 32%,22.6%,0%, with a smaller loss of antimicrobial activity.After Egg anti-drug experiments, the meat chicken anti-drug experiments and the big group of meat chicken experiment indicate that antimicrobial peptides feed additive has certain treatment with the illness caused by S. aureus ATCC 14458, and is helpful in enhancing the young chicken’s survival percentage, enhances the young chicken body weight and protecting the young chicken’s visceral organ, has strengthened the function of chicks itself the role of immunity.The experiment also further prepared microecological antimicrobial peptide formulations and optimized fermentation of bacillus conditions. Finally the optimal fermentation conditions of B. laterosporus S62-9 spores are:fermentation pH 7, the fermentation temperature 3℃, fermentation time 48 h, fermentation speed 350 r/min.