{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T00:15:15Z","timestamp":1792714515583,"version":"4.5.0"},"reference-count":37,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2013,1,16]],"date-time":"2013-01-16T00:00:00Z","timestamp":1358294400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Fructus crataegi (hawthorn) is the common name of all plant species in the genus Crataegus of the Rosaceae family. In the present study, three monomers of  (+)-catechin (C), (\u2212)-epicatechin gallate (ECg) and (\u2212)-epigallocatechin (EGC) were isolated from the hawthorn under the guide of antibacterial sensitization activity. The bioactivity of the composite fraction in enhancing the antibacterial effect of oxacillin against methicillin-resistant Staphylococcus aureus (MRSA) was greater than that of the individual monomer of the hawthorn extract in vitro. Two-fold dilution and checkerboard methods were used to analyze antibacterial activity and screen for the combination and proportion of monomers with the best bioactivity. The result showed that C (128 mg\/L) combined with ECg (16 mg\/L) had the greatest effect and the combination also reduced the bacterial load in blood of septic mice challenged with a sublethal dose of MRSA, increased daunomycin accumulation within MRSA and down-regulated the mRNA expression of norA, norC and abcA, three important efflux pumps of MRSA. In summary, C and ECg enhanced the antibacterial effect of \u03b2-lactam antibiotics against MRSA in vitro and in vivo, which might be related to the increased accumulation of antibiotics within MRSA via suppression of important efflux pumps\u2019 gene expression.<\/jats:p>","DOI":"10.3390\/ijms14011802","type":"journal-article","created":{"date-parts":[[2013,1,16]],"date-time":"2013-01-16T11:20:29Z","timestamp":1358335229000},"page":"1802-1821","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":70,"title":["The Combination of Catechin and Epicatechin Gallate from  Fructus Crataegi Potentiates \u03b2-Lactam Antibiotics Against Methicillin-Resistant Staphylococcus aureus (MRSA) in Vitro and in Vivo"],"prefix":"10.3390","volume":"14","author":[{"given":"Rongxin","family":"Qin","sequence":"first","affiliation":[{"name":"Department of Pharmacology, College of Pharmacy, The Third Military Medical University, Chongqing 400038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kangkang","family":"Xiao","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, College of Pharmacy, The Third Military Medical University, Chongqing 400038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bin","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, College of Pharmacy, The Third Military Medical University, Chongqing 400038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Weiwei","family":"Jiang","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, College of Pharmacy, The Third Military Medical University, Chongqing 400038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Peng","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, College of Pharmacy, The Third Military Medical University, Chongqing 400038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiang","family":"Zheng","sequence":"additional","affiliation":[{"name":"Medical Research Center, Southwestern Hospital, The Third Military Medical University, Chongqing 400038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hong","family":"Zhou","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, College of Pharmacy, The Third Military Medical University, Chongqing 400038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2013,1,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1093\/jac\/dkr437","article-title":"MRSA: The first half century","volume":"67","author":"Moellering","year":"2012","journal-title":"J. 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