{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,5]],"date-time":"2026-11-05T06:38:02Z","timestamp":1793860682496,"version":"4.6.1"},"reference-count":52,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2023,11,13]],"date-time":"2023-11-13T00:00:00Z","timestamp":1699833600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"King Mongkut\u2019s Institute of Technology Ladkrabang Research Fund","award":["-2565-02-16-001"],"award-info":[{"award-number":["-2565-02-16-001"]}]},{"name":"King Mongkut\u2019s Institute of Technology Ladkrabang Research Fund","award":["RGNS-64-245"],"award-info":[{"award-number":["RGNS-64-245"]}]},{"name":"Office of the Permanent Secretary, Ministry of Higher Education, Science, Research, and Innovation","award":["-2565-02-16-001"],"award-info":[{"award-number":["-2565-02-16-001"]}]},{"name":"Office of the Permanent Secretary, Ministry of Higher Education, Science, Research, and Innovation","award":["RGNS-64-245"],"award-info":[{"award-number":["RGNS-64-245"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Methicillin-resistant Staphylococcus aureus (MRSA), a global health concern, has prompted research into antibiotic adjuvants as a potential solution. Although our group previously reported the enhancing effects of gallic acid (GA) and methyl gallate (MG) on penicillin G activity against MRSA, the synergistic potential with other \u03b2-lactam antibiotics and the underlying mechanism have not been fully explored. Therefore, this study primarily aimed to investigate the antibacterial synergism with \u03b2-lactam antibiotics through disc diffusion, checkerboard, and time\u2013kill assays. The \u03b2-lactamase inhibition was also examined through both molecular modeling and in vitro experiments. Additionally, bacterial morphology changes were studied using a scanning electron microscopy (SEM). The results revealed that both GA and MG exhibited anti-MRSA activity and showed indifferent effects when combined with \u03b2-lactam antibiotics against methicillin susceptible S. aureus (MSSA). Interestingly, MG demonstrated synergism with only the \u03b2-lactamase-unstable antibiotics against MRSA with the lowest fractional inhibitory concentration (FIC) indexes of \u22643.75. However, GA and MG exhibited weak \u03b2-lactamase inhibition. Furthermore, GA, MG, and the combination with ampicillin induced the morphological changes in MRSA, suggesting a possible mechanism affecting the cell membrane. These findings suggest that MG could potentially serve as an adjunct to \u03b2-lactam antibiotics to combat MRSA infections.<\/jats:p>","DOI":"10.3390\/antibiotics12111622","type":"journal-article","created":{"date-parts":[[2023,11,13]],"date-time":"2023-11-13T08:35:52Z","timestamp":1699864552000},"page":"1622","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Assessing the Potential of Gallic Acid and Methyl Gallate to Enhance the Efficacy of \u03b2-Lactam Antibiotics against Methicillin-Resistant Staphylococcus aureus by Targeting \u03b2-Lactamase: In Silico and In Vitro Studies"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2746-6981","authenticated-orcid":false,"given":"Pimsumon","family":"Jiamboonsri","sequence":"first","affiliation":[{"name":"Faculty of Medicine, King Mongkut\u2019s Institute of Technology Ladkrabang, 1 Chalongkrung Road, Ladkrabang, Bangkok 10520, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chatchakorn","family":"Eurtivong","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Mahidol University, 447 Si Ayutthaya Road, Ratchathewi, Bangkok 10400, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8826-5008","authenticated-orcid":false,"given":"Sompit","family":"Wanwong","sequence":"additional","affiliation":[{"name":"Materials Technology Program, School of Energy, Environment and Materials, King Mongkut\u2019s University of Technology Thonburi, 126 Pracha Uthit Road, Thung Khru, Bangkok 10140, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"a025247","DOI":"10.1101\/cshperspect.a025247","article-title":"\u03b2-lactams and \u03b2-lactamase Inhibitors: An overview","volume":"6","author":"Bush","year":"2016","journal-title":"Cold Spring Harb. 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