{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,4]],"date-time":"2026-10-04T20:15:28Z","timestamp":1791144928845,"version":"4.1.0"},"reference-count":39,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2010,4,16]],"date-time":"2010-04-16T00:00:00Z","timestamp":1271376000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Marine Drugs"],"abstract":"<jats:p>Lobophora variegata, a brown alga collected from the coast of the Yucatan peninsula, Mexico, was studied for antiprotozoal activity against Giardia intestinalis, Entamoeba histolytica and Trichomonas vaginalis. The whole extract showed the highest activity against T. vaginalis, with an IC50 value of 3.2 mg\/mL. For the fractions, the best antiprotozoal activity was found in non-polar fractions. The chloroform fraction of the extract contained a major sulfoquinovosyldiacylglycerol (SQDG), identified as 1-O-palmitoyl-2-O-myristoyl-3-O-(6\u00b4\u00b4\u00b4-sulfo-a-D-quinovopyranosyl)-glycerol (1), together with small amounts of 1,2-di-O-palmitoyl-3-O-(6\u00b4\u00b4\u00b4-sulfo-a-D-quinovopyranosyl)-glycerol (2) and a new compound identified as 1-O-palmitoyl-2-O-oleoyl-3-O-(6\u00b4\u00b4\u00b4-sulfo-a-D-quinovopyranosyl)-glycerol (3). Their structures were elucidated on the basis of chemical and enzymatic hydrolysis and careful analysis of FAB-MS and NMR spectroscopic data. This is the first report on the isolation of SQDGs from L. variegata. The mixture of 1\u20133 showed good activity against E. histolytica and moderate activity against T. vaginalis with IC50s of 3.9 and 8.0 mg\/mL, respectively, however, the activity of 1\u20133 is not as effective as metronidazole. These results afford ground information for the potential use of the whole extract and fractions of this species in protozoal infections.<\/jats:p>","DOI":"10.3390\/md8041292","type":"journal-article","created":{"date-parts":[[2010,4,16]],"date-time":"2010-04-16T10:47:38Z","timestamp":1271414858000},"page":"1292-1304","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":58,"title":["The Tropical Brown Alga Lobophora variegata: A Source of Antiprotozoal Compounds"],"prefix":"10.3390","volume":"8","author":[{"given":"Zulema","family":"Cantillo-Ciau","sequence":"first","affiliation":[{"name":"Department of Marine Resources, Cinvestav, Km 6 Carretera Antigua a Progreso, Cordemex, 97310, A.P. 73, M\u00e9rida, Yucat\u00e1n, M\u00e9xico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rosa","family":"Moo-Puc","sequence":"additional","affiliation":[{"name":"Unidad de Investigaci\u00f3n M\u00e9dica Yucat\u00e1n, Unidad M\u00e9dica de Alta Especialidad, Centro M\u00e9dico Ignacio Garc\u00eda T\u00e9llez, Instituto Mexicano del Seguro Social, 41 No. 439 x 32 y 34, Col. Industrial, CP 97150, M\u00e9rida, Yucat\u00e1n, M\u00e9xico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Leovigildo","family":"Quijano","sequence":"additional","affiliation":[{"name":"Instituto de Qu\u00edmica, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Circuito Exterior, Ciudad Universitaria, Coyoac\u00e1n, 04510 M\u00e9xico City, M\u00e9xico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yolanda","family":"Freile-Pelegr\u00edn","sequence":"additional","affiliation":[{"name":"Department of Marine Resources, Cinvestav, Km 6 Carretera Antigua a Progreso, Cordemex, 97310, A.P. 73, M\u00e9rida, Yucat\u00e1n, M\u00e9xico"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2010,4,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"235","DOI":"10.1016\/S0020-7519(02)00267-9","article-title":"Molecular biology of the amitochondriate parasites, Giardia intestinalis, Entamoeba histolytica and Trichomonas vaginalis","volume":"33","author":"Vanacova","year":"2003","journal-title":"Int J Parasitol"},{"key":"ref_2","unstructured":"(1997). 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