Antimicrobial activity of Nepeta tenuifolia on Shewanella algae SYT4 with its genome annotation
| Autor: | Yi-Hsuan Lee, 李宜璇 |
|---|---|
| Rok vydání: | 2019 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 107 The antimicrobials are administered at therapeutic dosages, which clearly differentiate from that used to lower dose of prophylactic use. However, antibiotic overuse has created the selection of resistance according to the multi-resistance pathogens reports. Prophylactic uses of antimicrobials are common in veterinary practice than in human clinics. Many recent studies concerning the essential oils and extracts of plants from genus Mentha have aimed to show the potential therapy in infections. Particularly, the antimicrobactrial effects against such as bacteria, fungi, and virus have been studied. The genus Mentha and Nepeta belong to the mint family and are frequently combined with different formulas for treatment of some infections, headaches, common cold, and influenza. The purpose of this study was to confirm the essential oils of the Schizonepeta tenuifolia Briq on the different multi-resistant pathogens activity. In addition, the active compound in the flowers of Schizonepeta tenuifolia Briq was identified by LC- MS/MS analysis in this study. The result showed that the main compounds are composed of pulegone and it contains more than 85% purity. Overall, the essential oils also presented strong inhibitory action against all tested reference strains and isolations. The essential oil was against all reference bacteria, especially S. enterica, C. freundii, and E. coli. Of these, MIC for S. enterica ranged from 0.081-0.78 % and E. coli (0.097- 0.39 %), C. freundii (0.39-0.78%) by MIC determination, corresponding MBC values varied ranged from 0.097% to 1.04%. In addition, the susceptibility data also provided clinical isolations outcome which showed that be effective for the management of Staphylococcus pseudintermedius、E. coli. Based on analysis of MIC values of environment isolates Shewanella algae SYT3 and SYT4 which were isolated from Asian hard clam (Meretrix lusoria), showed susceptible to the essential oils of the Schizonepeta tenuifolia Briq. However, the results of antibacterial activity of essential oils showed intermediate susceptibility or strong resistant to P. aureginosa reference strains and clinical isolates. According to the susceptibility data, S. algae SYT4 showed the characteristic of multi-resistantance. It has little knowledge about the S. algae of resistance genes, especially the mechanism of resistance genes spread from the environment. Consideration of antibiotics resistance in S. algae SYT4, we also identified by whole genome sequence assay and revealed blaOXA-55-type β-lactamase genes, dfrA3 gene, mfd, and qnrA3; Resistance-Nodulation-Division (RND) efflux systems genes and efflux pump regulatory genes which may contribute to bacterial antibiotic resistance in this study. In this study, we provided the S. tenuifolia Briq. extracted oils on the different multi-resistant pathogens activity as alternative strategies of antibiotic. Furthermore, we report the whole genome sequence and genome annotation of S. algae strain SYT4, related to carbapenem resistance for further study. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|