Antimicrobial Effects and Mechanisms of Ethanol Extracts of Psoralea corylifolia Seeds Against Listeria monocytogenes and Methicillin-Resistant Staphylococcus aureus
Journal
Foodborne Pathogens and Disease
Journal Volume
16
Journal Issue
8
Date Issued
2019-08-01
Author(s)
Abstract
Copyright © 2019 Mary Ann Liebert, Inc. Psoralea corylifolia seeds contain many bioactive compounds commonly used in traditional Chinese medicine. In this study, the antibacterial activity and possible mechanism of P. corylifolia seed ethanol extract (PCEE) against foodborne pathogens were investigated. Both methicillin-resistant Staphylococcus aureus (MRSA) and Listeria monocytogenes had similar minimum inhibitory concentrations and minimum bactericidal concentrations of PCEE at 50 and 100 μg/mL, respectively. Furthermore, elevated OD260, protein concentration, and electric conductivity indicated irreversible damage to the cytoplasmic membranes of PCEE-treated cells. Indeed, the treated cells displayed disrupted membranes, incomplete and deformed shapes, and rupture as visualized by scanning electron microscopy. Multidrug-resistance efflux pump gene expression was also analyzed by quantitative reverse transcription PCR. Although the mdrL, mdrT, and lde genes of L. monocytogenes and the mepA gene of MRSA were upregulated, there was no significant difference that indicated an attempt by the efflux pumps to discharge PCEE. MRSA norA expression and abcA expression were significantly downregulated (p < 0.05). A possible mechanism for PCEE may be to cause an energy depletion, either by inhibiting adenosine triphosphate binding or by disturbing the proton gradient, resulting in membrane damage.
Subjects
antimicrobial mechanisms | Listeria monocytogenes | methicillin-resistant Staphylococcus aureus | Psoralea corylifolia | RT-qPCR
SDGs
Other Subjects
Psoralea corylifolia extract; antiinfective agent; plant extract; antimicrobial activity; Article; cell membrane permeability; cell structure; Cullen corylifolium; down regulation; drug mechanism; electric conductivity; gene expression; Listeria monocytogenes; methicillin resistant Staphylococcus aureus; minimum bactericidal concentration; minimum inhibitory concentration; multidrug resistance; nonhuman; plant seed; priority journal; reverse transcription polymerase chain reaction; scanning electron microscopy; upregulation; drug effect; food control; human; Listeria monocytogenes; methicillin resistant Staphylococcus aureus; microbial sensitivity test; Psoralea; Anti-Infective Agents; Food Microbiology; Humans; Listeria monocytogenes; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Plant Extracts; Psoralea; Seeds
Type
journal article