title: Zoapatle. XII. In vitro effect of kaurenoic acid isolated from Montanoa frutescens and two derivatives upon human spermatozoa.
abstract: Zoapatle aqueous crude extract (ZACE) from Montanoa tomentosa has been used as an oral contraceptive in traditional Mexican medicine for centuries. Kaurenoic acid, as isolated from Montanoa frutescens, and the methyl esters of 15-hydroxy-dihydro-kaurenoic acid and 15-keto-dihydro-kaurenoic acid were tested in vitro on human sperm motility and viability. The estimated ED50 concentrations immobilization were 374, 126 and 58 micrograms/ml, respectively using 15 X 10(6) sperms/500 microliter. Kaurenoic acid and both of its derivatives displayed only weak to negligible capacity for killing human sperms.
mesh_terms: D004224:Diterpenes / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008800:Mexico; D010946:Plants, Medicinal / Q000032:analysis*; D013081:Sperm Motility / Q000187:drug effects; D013089:Spermatocidal Agents / Q000494:pharmacology*; D013094:Spermatozoa / Q000187:drug effects*; D014700:Verapamil / Q000494:pharmacology
chemical_list: D004224:Diterpenes; D013089:Spermatocidal Agents; C051443:15-hydroxydihydrokaurenoic acid methyl ester; C051436:kaurenoic acid; C051444:15-ketodihydrokaurenoic acid methyl ester; D014700:Verapamil