The Rapid Extraction And Preparation Technology Of Antimicrobial Peptides Of Brevibacillus Laterosporus

Antibacterial peptides(AMPs)are derived from a variety of creatures,which can inhibit or kill many pathogenic bacteria,as a potential substitute for feed additives instead of antibiotics.However,large scale production of antimicrobial peptides is difficult to achieve due to the high production cost caused by the complicated steps of the separation and purification.This study established a rapid extraction method of preparation of B.laterosporus antibacterial peptide,explored the adsorption mechanism and preparation of antibacterial peptides,and studied the antimicrobial activ:ity and storage stability of antibacterial peptide products,which laid the foundation for the application of antibacterial peptide in feed additives.According to the characteristics of low price and easy absorption of wheat bran,soybean meal,rice bran and other agricultural,this study optimized the rapid adsorption extraction process of antibacterial peptide.Taking the adsorption rate and antibacterial effect of antibacterial peptide into consideration,the optimal adsorbent was screened,which is rice bran.the absorption efficiency of rice bran can be significantly improved by sieving over 50 mesh followed by cleaning with deionized water,before adsorption.the preparation process of antimicrobial peptide was optimized by response surface test,and the adsorption rate of antibacterial peptide can reach 88%under the condition of 48.5?,pH 7,adding 4.2%(m/v),shaking speed 200 r/min,adsorption time 2 h.This study simplified the process of extraction of antimicrobial peptides,and realized the fast extraction of antimicrobial peptides,which laid the foundation for the large scale production of antimicrobial peptides.This experiment was conducted to study the antimicrobial spectrum and stability of AMP-rice bran.And AMP-rice bran showed widely antimicrobial spectrum for Inhibiting many gram positive and gram negative bacterias.The antibacterial activity of AMP-rice bran was not signif cantly reduced through the treatment of heating at 100? for 120 min,radiating by 4500 Lx for 10 days,and storaging at room temperature or 4 C for 14 weeks,respectively.But with the increase or decrease of pH,the activity of AMP-rice bran would gradually reduce,and at pH 2 or pH 11,the loss ratio of activity reached 20%.The model of the adsorption extraction process for AMP-rice bran was fitted,and the results show that the adsorption process of antibacterial peptide fits well with Langmuir adsorption isotherm model and pseudo two order kinetics equation can interpration.SEM results show that the antibacterial peptide was closely adsorbed on the surface of rice bran.FTIR results show that hydroxyl(association hydroxyl,phenolic hydroxyl group),carbonyl(carboxyl carbonyl,ketone carbonyl)could be the active groups involved in the adsorption process.