Study on isolation and characterization of an antimicrobial peptide from marine Bacillus halotolerans B7
YAN Hesong
LI Chanjuan
XU Zhao
Abstract：The experiment aimed to isolate antimicrobial peptides from marine derived Bacillus halotolerans B7 and explore their physicochemical properties.The target antibacterial peptide was purified by ammonium sulfate salting out and gel filtration chromatography,and its physical and chemical properties,antibacterial spectrum and action mechanism were analyzed.The results showed that the Bacillus halotolerans B7 antimicrobial peptides exhibits broad-spectrum antimicrobial activity,showing significant inhibition against multiple animal pathogens.The Bacillus halotolerans B7 peptide maintained strong activity within a pH value range of 4.0 to 10.5 and retained 25％of its activity after heat treatment at 100 ℃ for 20 minutes.It displayed high tolerance to trypsin and pepsin but was sensitive to proteinase K.The minimum inhibitory concentrations against Pseudomonas putida and Staphylococcus aureus were 12.89 and 206.14 mg/L,respectively.Transmission electron microscopy result showed that the antimicrobial peptides disrupted bacterial cell wall and membrane integrity,leading to cytoplasmic leakage.The study indicates that the broad-spectrum,pH adaptability,heat resistance and protease tolerance of the marine Bacillus halotolerans B7 antimicrobial peptide meet the requirements of the feed industry.
Keywords：Bacillus halotoleransantimicrobial peptidesisolation and purificationphysicochemical properties
Publication Date：2025-07-28
Online Publishing Date：2025-09-18(First online date of this platform, not the publication date of the document)
Pages：6( 113-118 )