{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T05:09:06Z","timestamp":1790399346907,"version":"4.1.0"},"reference-count":56,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,2,27]],"date-time":"2022-02-27T00:00:00Z","timestamp":1645920000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Research Grants Council of the Hong Kong Special Administrative Region, China","award":["HKBU 12103917"],"award-info":[{"award-number":["HKBU 12103917"]}]},{"name":"The Research Grants Council of the Hong Kong Special Administrative Region, China","award":["HKBU 12103618"],"award-info":[{"award-number":["HKBU 12103618"]}]},{"name":"National Institutes of Health (NIH)","award":["AI77767"],"award-info":[{"award-number":["AI77767"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Ebola virus disease (EVD), a disease caused by infection with Ebola virus (EBOV), is characterized by hemorrhagic fever and a high case fatality rate. With limited options for the treatment of EVD, anti-Ebola viral therapeutics need to be urgently developed. In this study, over 500 extracts of medicinal plants collected in the Lingnan region were tested against infection with Ebola-virus-pseudotyped particles (EBOVpp), leading to the discovery of Maesa perlarius as an anti-EBOV plant lead. The methanol extract (MPBE) of the stems of this plant showed an inhibitory effect against EBOVpp, with an IC50 value of 0.52 \u00b5g\/mL, which was confirmed by testing the extract against infectious EBOV in a biosafety level 4 laboratory. The bioassay-guided fractionation of MPBE resulted in three proanthocyanidins (procyanidin B2 (1), procyanidin C1 (2), and epicatechin-(4\u03b2\u21928)-epicatechin-(4\u03b2\u21928)-epicatechin-(4\u03b2\u21928)-epicatechin (3)), along with two flavan-3-ols ((+)-catechin (4) and (\u2212)-epicatechin (5)). The IC50 values of the compounds against pseudovirion-bearing EBOV-GP ranged from 0.83 to 36.0 \u00b5M, with 1 as the most potent inhibitor. The anti-EBOV activities of five synthetic derivatives together with six commercially available analogues, including EGCG ((\u2212)-epigallocatechin-3-O-gallate (8)), were further investigated. Molecular docking analysis and binding affinity measurement suggested the EBOV glycoprotein could be a potential molecular target for 1 and its related compounds.<\/jats:p>","DOI":"10.3390\/ijms23052620","type":"journal-article","created":{"date-parts":[[2022,2,27]],"date-time":"2022-02-27T20:47:17Z","timestamp":1645994837000},"page":"2620","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Ebola Entry Inhibitors Discovered from Maesa perlarius"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8273-3114","authenticated-orcid":false,"given":"Nga Yi","family":"Tsang","sequence":"first","affiliation":[{"name":"Teaching and Research Division, School of Chinese Medicine, Hong Kong Baptist University, Kowloon, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wan-Fei","family":"Li","sequence":"additional","affiliation":[{"name":"Teaching and Research Division, School of Chinese Medicine, Hong Kong Baptist University, Kowloon, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5229-7465","authenticated-orcid":false,"given":"Elizabeth","family":"Varhegyi","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, College of Medicine, University of Illinois Chicago, 909 South Wolcott Ave, Chicago, IL 60612, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lijun","family":"Rong","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, College of Medicine, University of Illinois Chicago, 909 South Wolcott Ave, Chicago, IL 60612, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7175-5166","authenticated-orcid":false,"given":"Hong-Jie","family":"Zhang","sequence":"additional","affiliation":[{"name":"Teaching and Research Division, School of Chinese Medicine, Hong Kong Baptist University, Kowloon, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,27]]},"reference":[{"key":"ref_1","unstructured":"Centers for Disease Control and Prevention (CDC) (2022, February 01). 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