{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T08:23:30Z","timestamp":1777537410181,"version":"3.51.4"},"reference-count":39,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,3,7]],"date-time":"2022-03-07T00:00:00Z","timestamp":1646611200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100013704","name":"Consejo Nacional de Ciencia y Tecnolog\u00eda","doi-asserted-by":"publisher","award":["PINV 20-006"],"award-info":[{"award-number":["PINV 20-006"]}],"id":[{"id":"10.13039\/501100013704","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002848","name":"Agencia Nacional de Investigaci\u00f3n y Desarrollo","doi-asserted-by":"publisher","award":["FONDECYT 1190156"],"award-info":[{"award-number":["FONDECYT 1190156"]}],"id":[{"id":"10.13039\/501100002848","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002848","name":"Agencia Nacional de Investigaci\u00f3n y Desarrollo","doi-asserted-by":"publisher","award":["FONDECYT 1180798"],"award-info":[{"award-number":["FONDECYT 1180798"]}],"id":[{"id":"10.13039\/501100002848","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The COVID-19 pandemic has led to the search for new molecules with antiviral activity against SARS-CoV-2. The entry of the virus into the cell is one of the main targets for inhibiting SARS-CoV-2 infection. Natural products are an important source of new therapeutic alternatives against diseases. Pseudotyped viruses allow the study of SARS-CoV-2 viral entry inhibitors, and due to their simplicity, they allow the screening of a large number of antiviral candidates in Biosafety Level 2 facilities. We used pseudotyped HIV-1 with the D614G SARS-CoV-2 spike glycoprotein to test its ability to infect ACE2-expressing HEK 293T cells in the presence of diverse natural products, including 21 plant extracts, 7 essential oils, and 13 compounds from plants and fungi. The 50% cytotoxic concentration (CC50) was evaluated using the resazurin method. From these analyses, we determined the inhibitory activity of the extract of Stachytarpheta cayennensis, which had a half-maximal inhibitory concentration (IC50) of 91.65 \u00b5g\/mL, a CC50 of 693.5 \u00b5g\/mL, and a selectivity index (SI) of 7.57, indicating its potential use as an inhibitor of SARS-CoV-2 entry. Moreover, our work indicates the usefulness of the pseudotyped-virus system in the screening of SARS-CoV-2 entry inhibitors.<\/jats:p>","DOI":"10.3390\/molecules27051743","type":"journal-article","created":{"date-parts":[[2022,3,9]],"date-time":"2022-03-09T01:53:54Z","timestamp":1646790834000},"page":"1743","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":36,"title":["Screening of Natural Products Inhibitors of SARS-CoV-2 Entry"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7972-2193","authenticated-orcid":false,"given":"Pamela","family":"Gonz\u00e1lez-Maldonado","sequence":"first","affiliation":[{"name":"Biotechnology Department, Facultad de Ciencias Qu\u00edmicas, Universidad Nacional de Asunci\u00f3n, San Lorenzo 111421, Paraguay"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nelson","family":"Alvarenga","sequence":"additional","affiliation":[{"name":"Phytochemistry Department, Facultad de Ciencias Qu\u00edmicas, Universidad Nacional de Asunci\u00f3n, San Lorenzo 111421, Paraguay"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8286-8556","authenticated-orcid":false,"given":"Alberto","family":"Burgos-Edwards","sequence":"additional","affiliation":[{"name":"Phytochemistry Department, Facultad de Ciencias Qu\u00edmicas, Universidad Nacional de Asunci\u00f3n, San Lorenzo 111421, Paraguay"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ma. Eugenia","family":"Flores-Giubi","sequence":"additional","affiliation":[{"name":"Biological Chemistry Department, Facultad de Ciencias Qu\u00edmicas, Universidad Nacional de Asunci\u00f3n, San Lorenzo 111421, Paraguay"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8164-3432","authenticated-orcid":false,"given":"Javier E.","family":"Bar\u00faa","sequence":"additional","affiliation":[{"name":"Biological Chemistry Department, Facultad de Ciencias Qu\u00edmicas, Universidad Nacional de Asunci\u00f3n, San Lorenzo 111421, Paraguay"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ma. Cristina","family":"Romero-Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"Biological Chemistry Department, Facultad de Ciencias Qu\u00edmicas, Universidad Nacional de Asunci\u00f3n, San Lorenzo 111421, Paraguay"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0945-2970","authenticated-orcid":false,"given":"Ricardo","family":"Soto-Rifo","sequence":"additional","affiliation":[{"name":"Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago 834100, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9156-2516","authenticated-orcid":false,"given":"Fernando","family":"Valiente-Echeverr\u00eda","sequence":"additional","affiliation":[{"name":"Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago 834100, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9793-3373","authenticated-orcid":false,"given":"Patricia","family":"Langjahr","sequence":"additional","affiliation":[{"name":"Biotechnology Department, Facultad de Ciencias Qu\u00edmicas, Universidad Nacional de Asunci\u00f3n, San Lorenzo 111421, Paraguay"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guadalupe","family":"Cantero-Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Biotechnology Department, Facultad de Ciencias Qu\u00edmicas, Universidad Nacional de Asunci\u00f3n, San Lorenzo 111421, Paraguay"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6473-2134","authenticated-orcid":false,"given":"Pablo H.","family":"Sotelo","sequence":"additional","affiliation":[{"name":"Biotechnology Department, Facultad de Ciencias Qu\u00edmicas, Universidad Nacional de Asunci\u00f3n, San Lorenzo 111421, Paraguay"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1038\/s41579-020-00459-7","article-title":"Characteristics of SARS-CoV-2 and COVID-19","volume":"19","author":"Hu","year":"2021","journal-title":"Nat. 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