{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T16:47:40Z","timestamp":1777740460368,"version":"3.51.4"},"reference-count":74,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,11,29]],"date-time":"2021-11-29T00:00:00Z","timestamp":1638144000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Metabolites"],"abstract":"<jats:p>Coronavirus disease 2019 (COVID-19) is the disease caused by the virus SARS-CoV-2 responsible for the ongoing pandemic which has claimed the lives of millions of people. This has prompted the scientific research community to act to find treatments against the SARS-CoV-2 virus that include safe antiviral medicinal compounds. The edible green algae U.\u00a0lactuca. is known to exhibit diverse biological activities such as anti-influenza virus, anti-Japanese encephalitis virus, immunomodulatory, anticoagulant, antioxidant and antibacterial activities. Herein, four new ceramides in addition to two known ones were isolated from Ulva\u00a0lactuca. The isolated ceramides, including Cer-1, Cer-2, Cer-3, Cer-4, Cer-5 and Cer-6 showed promising antiviral activity against SARS-CoV-2 when investigated using in silico approaches by preventing its attachment to human cells and\/or inhibiting its viral replication. Cer-4 and Cer-5 were the most effective in inhibiting the human angiotensin converting enzyme (hACE)\u2013spike protein complex which is essential for the virus to enter the human host. In addition to this, Cer-4 also showed an inhibition of the SARS-CoV-2 protease (Mpro) that is responsible for its viral replication and transcription. In this study, we also used liquid chromatography coupled to electrospray ionization high-resolution mass spectroscopy (LC-ESI-HRMS) to identify several metabolites of U.\u00a0lactuca, including metabolites such as fatty acids, their glyceride derivatives, terpenoids, sterols and oxysterols from the organic extract. Some of these metabolites also possessed promising antiviral activity, as previously reported.<\/jats:p>","DOI":"10.3390\/metabo11120816","type":"journal-article","created":{"date-parts":[[2021,11,30]],"date-time":"2021-11-30T05:42:10Z","timestamp":1638250930000},"page":"816","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Chemical Composition of the Red Sea Green Algae Ulva lactuca: Isolation and In Silico Studies of New Anti-COVID-19 Ceramides"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1607-4285","authenticated-orcid":false,"given":"Enas E.","family":"Eltamany","sequence":"first","affiliation":[{"name":"Department of Pharmacognosy, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3799-0581","authenticated-orcid":false,"given":"Sameh S.","family":"Elhady","sequence":"additional","affiliation":[{"name":"Department of Natural Products, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9291-8940","authenticated-orcid":false,"given":"Marwa S.","family":"Goda","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Omar M.","family":"Aly","sequence":"additional","affiliation":[{"name":"Department of Medicinal Chemistry, Faculty of Pharmacy, Minia University, 61519 Minia, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eman S.","family":"Habib","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Amany K.","family":"Ibrahim","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hashim A.","family":"Hassanean","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1014-6922","authenticated-orcid":false,"given":"Usama Ramadan","family":"Abdelmohsen","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy, Faculty of Pharmacy, Minia University, Minia 61519, Egypt"},{"name":"Department of Pharmacognosy, Faculty of Pharmacy, Deraya University, New Minia 61111, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9536-1743","authenticated-orcid":false,"given":"Martin K.","family":"Safo","sequence":"additional","affiliation":[{"name":"Department of Medicinal Chemistry, and Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23219, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Safwat A.","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8801","DOI":"10.1128\/JVI.77.16.8801-8811.2003","article-title":"The coronavirus spike protein is a class I virus fusion protein: Structural and functional characterization of the fusion core complex","volume":"77","author":"Bosch","year":"2003","journal-title":"J. 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