{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T03:19:54Z","timestamp":1790824794559,"version":"4.1.0"},"reference-count":17,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,2,20]],"date-time":"2023-02-20T00:00:00Z","timestamp":1676851200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Japan Agency for Medical Research and Development (AMED)","award":["20fk0108277h0001"],"award-info":[{"award-number":["20fk0108277h0001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>We report for the first time that ephedrine alkaloids-free Ephedra Herb extract (EFE) directly inhibits the replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in vitro and that the addition of EFE to the culture medium before viral infection reduces virus titers in the culture supernatant of SARS-CoV-2, including those of variant strains, by more than 99%, 24 h after infection. The addition of Ephedra Herb macromolecule condensed-tannin, which is the main active ingredient responsible for the anticancer, pain suppression, and anti-influenza effects of EFE, similarly suppressed virus production in the culture supernatant by 99% before infection and by more than 90% after infection. Since EFE does not have the side effects caused by ephedrine alkaloids, such as hypertension, palpitations, and insomnia, our results showed the potential of EFE as a safe therapeutic agent against coronavirus disease 2019.<\/jats:p>","DOI":"10.3390\/microorganisms11020534","type":"journal-article","created":{"date-parts":[[2023,2,20]],"date-time":"2023-02-20T06:37:59Z","timestamp":1676875079000},"page":"534","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Antiviral Effect of Ephedrine Alkaloids-Free Ephedra Herb Extract against SARS-CoV-2 In Vitro"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7792-7339","authenticated-orcid":false,"given":"Masashi","family":"Uema","sequence":"first","affiliation":[{"name":"National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Masashi","family":"Hyuga","sequence":"additional","affiliation":[{"name":"National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kenzo","family":"Yonemitsu","sequence":"additional","affiliation":[{"name":"National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama 208-0011, Tokyo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sumiko","family":"Hyuga","sequence":"additional","affiliation":[{"name":"Oriental Medicine Research Center, Kitasato University, 5\u20139-1 Shirokane, Minato-ku, Tokyo 108-8642, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshiaki","family":"Amakura","sequence":"additional","affiliation":[{"name":"College of Pharmaceutical Sciences, Matsuyama University, 4-2 Bunkyo-cho, Matsuyama 790-8578, Ehime, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nahoko","family":"Uchiyama","sequence":"additional","affiliation":[{"name":"National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kazushige","family":"Mizoguchi","sequence":"additional","affiliation":[{"name":"Kampo Research & Development Division, Tsumura & Co., 3586 Yoshiwara, Ami-machi, Inashiki-gun 300-1192, Ibaraki, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8863-1557","authenticated-orcid":false,"given":"Hiroshi","family":"Odaguchi","sequence":"additional","affiliation":[{"name":"Oriental Medicine Research Center, Kitasato University, 5\u20139-1 Shirokane, Minato-ku, Tokyo 108-8642, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yukihiro","family":"Goda","sequence":"additional","affiliation":[{"name":"National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,20]]},"reference":[{"key":"ref_1","unstructured":"WHO (2022, December 30). 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