In Vitro Synergy of <i>Pongamia pinnata</i> Extract in Combination with Antibiotics for Inhibiting and Killing Methicillin-Resistant <i>Staphylococcus aureus</i>

• Main Authors: Po-An Su (Author), Shun-Lai Li (Author), Hung-Jen Tang (Author), Chi-Chung Chen (Author), Ying-Chen Lu (Author), Kuo-Chen Cheng (Author), Yi-Chung Lin (Author), Yin-Ching Chuang (Author), Chih-Cheng Lai (Author)
• Format: Book
• Published: MDPI AG, 2020-02-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

Aims: Currently, we face the serious problem of multiple drug-resistant pathogens. The development of new antimicrobial agents is very costly and time-consuming. Therefore, the use of medicinal plants as a source of alternative antibiotics or for enhancing antibiotic effectiveness is important. Methods: The antibacterial effects of aqueous extracts of the seed coat of <i>Pongamia pinnata</i> (Linn.) Pierre in combination with several antibiotics against methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) were tested by broth dilution, checkerboard, and time-kill methods. Results: For the combinations of <i>P. pinnata</i> with ampicillin, meropenem, cefazolin, cefotaxime, cefpirome, and cefuroxime, 70% to 100% were synergistic, with a fractional inhibitory concentration (FIC) index of < 0.5. For the time-kill method with 0.5&#215; minimum inhibitory concentration (MIC) of <i>P. pinnata</i> in combination with 8, 4, 2, and 1 &#181;g mL^&#8722;1 of the various antibiotics, almost all of the combinations showed synergistic effects, even with the lowest concentrations of <i>P. pinnata</i>, except for aztreonam. No antagonistic effect was observed for these combinations. Conclusions: Based on these findings, aqueous seed coat extracts of <i>P. pinnata</i> have good potential for the design of new antimicrobial agents.

Item Description

2079-6382
10.3390/antibiotics9030103