Isolation, Characterization and Antiproliferative Activity of New Metabolites from the South African Endemic Red Algal Species Laurencia alfredensis.
The marine red algae of the genusLaurenciahave been widely studied for their structurally diverse and biologically active secondary metabolites. We report here the natural product investigation of the organic extract of a newly identified South African endemic species,Laurencia alfredensis. A sequence of column chromatography, preparative TLC and normal phase HPLC resulted in the isolation of eleven compounds comprising three labdane-type diterpenes (1-3), four polyether triterpenes (4-7), three cholestane-type ecdysteroids (8-10) and a glycolipid (11). Compounds1-3,5-8and10have not previously been reported, while compound9is reported here for the first time from a natural source and the known compound11isolated for the first time from the genusLaurencia. The structural elucidation and the relative configuration assignments of the compounds were accomplished by extensive use of 1D- and 2D-NMR, HR-ESI-MS, UV and IR spectroscopic techniques, while the absolute configuration of compound1was determined by single-crystal X-ray diffraction analysis. All compounds were evaluated against the MDA-MB-231 breast and HeLa cervical cancer cell lines. Compound2exhibited low micromolar antiproliferative activity (IC50= 9.3 µM) against the triple negative breast carcinoma and compound7was similarly active (IC50= 8.8 µM) against the cervical cancer cell line.
Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa. dzwgod001@myuct.ac.za.
Godwin A
GA
Dziwornu
Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa. mino.caira@uct.ac.za.
Mino R
MR
Caira
Biomedical Biotechnology Research Unit, Department of Biochemistry and Microbiology, Rhodes University, Grahamstown 6140, South Africa. j.delamare@ru.ac.za.
Jo-Anne de la
JA
Mare
Biomedical Biotechnology Research Unit, Department of Biochemistry and Microbiology, Rhodes University, Grahamstown 6140, South Africa. a.edkins@ru.ac.za.
Adrienne L
AL
Edkins
Department of Biological Sciences, University of Cape Town, Rondebosch 7701, South Africa. john.bolton@uct.ac.za.|Marine Research (Ma-Re) Institute, University of Cape Town, Rondebosch 7701, South Africa. john.bolton@uct.ac.za.
John J
JJ
Bolton
School of Pharmacy Department of Pharmaceutical Chemistry, University of the Western Cape, Bellville 7535, South Africa. dbeukes@uwc.ac.za.
Denzil R
DR
Beukes
Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa. sunny.sunassee@uct.ac.za.|Marine Research (Ma-Re) Institute, University of Cape Town, Rondebosch 7701, South Africa. sunny.sunassee@uct.ac.za.|South African Medical Research Council Drug Discovery and Development Research Unit, University of Cape Town, Rondebosch 7701, South Africa. sunny.sunassee@uct.ac.za.
Suthananda N
SN
Sunassee
D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D018360:Crystallography, X-Ray; D004354:Drug Screening Assays, Antitumor; D026461:Ecdysteroids / Q000302:isolation & purification* / Q000494:pharmacology; D006017:Glycolipids / Q000302:isolation & purification* / Q000494:pharmacology; D006367:HeLa Cells; D006801:Humans; D044722:Laurencia / Q000737:chemistry*; D015394:Molecular Structure; D013729:Terpenes / Q000302:isolation & purification* / Q000494:pharmacology; D014315:Triterpenes / Q000737:chemistry
D026461:Ecdysteroids; D006017:Glycolipids; D013729:Terpenes; D014315:Triterpenes
Rhodomelaceae; antiproliferative activity; cholestane-type ecdysteroids; glycolipid; labdane-type diterpenes; polyether triterpenes