title: Antibacterial mechanism and activities of black pepper chloroform extract.
abstract: Black pepper extracts reportedly inhibit food spoilage and food pathogenic bacteria. This study explored the antimicrobial activity of black pepper chloroform extract (BPCE) against Escherichia coli and Staphylococcus aureus. The antibacterial mechanism of BPCE was elucidated by analyzing the cell morphology, respiratory metabolism, pyruvic acid content, and ATP levels of the target bacteria. Scanning electron micrographs showed that the bacterial cells were destroyed and that plasmolysis was induced. BPCE inhibited the tricarboxylic acid pathway of the bacteria. The extract significantly increased pyruvic acid concentration in bacterial solutions and reduced ATP level in bacterial cells. BPCE destroyed the permeability of the cell membrane, which consequently caused metabolic dysfunction, inhibited energy synthesis, and triggered cell death.
authors.affiliation: College of Food Science and Technology, Hainan University, Haikou, China.
authors.forename: Lan
authors.initials: L
authors.lastname: Zou
authors.affiliation: College of Materials and Chemical Engineering, Hainan University, Haikou, China.
authors.forename: Yue-Ying
authors.initials: YY
authors.lastname: Hu
authors.affiliation: College of Food Science and Technology, Hainan University, Haikou, China.
authors.forename: Wen-Xue
authors.initials: WX
authors.lastname: Chen
keywords: ATP; Antibacterial mechanism; Black pepper; Chloroform extract; Respiration metabolism