title: Bioactivity and chemistry of the genus Hortonia.
abstract: The dichloromethane extracts of the leaves, stem bark, bark and the roots of the three species of the primitive endemic genus Hortonia, H. angustifolia, H. floribunda and H. ovalifolia, collected from nine geographical locations ranging from lower elevations (84-420 m) to higher (2000 m) showed comparable HPLC profiles and mosquito larvicidal and antifungal activities; protein analysis of the leaves of the three species of Hortonia showed identical peaks and bands. The two major metabolites (4S)-4-methyl-2-(11-dodecynyl)-2-butenolide (2) and (4S)-4-methyl-2-(11-dodecenyl)-2-butenolide (3), which were previously reported from all three plants, showed potent larvicidal activities. Compound 2 was excessively high in the extracts of the stem bark and the roots of all three species amounting to approximately 38 and 60%, respectively. A minor new butenolide (4), (4S)-4-methyl-2-((2R)-hydroxy-11-dodecenyl)-2-butenolide, with much reduced larvicidal activity and ishwarane (1), which showed antifungal activity, were also isolated from all three plants. Treatment of compound 2 with H(2)/Pd-C afforded the completely reduced compound 5, which showed no larvicidal activity, indicating that unsaturation in both 2 and 3 is necessary for their bioactivity. The foregoing evidence showed that there are major similarities between the three species of Hortonia.
authors.affiliation: Department of Chemistry, University of Peradeniya, Peradeniya, Sri Lanka.
authors.forename: Rukmal
authors.initials: R
authors.lastname: Ratnayake
authors.forename: B M
authors.initials: BM
authors.lastname: Ratnayake Bandara
authors.forename: Siril
authors.initials: S
authors.lastname: Wijesundara
authors.forename: John K
authors.initials: JK
authors.lastname: Macleod
authors.forename: Peta
authors.initials: P
authors.lastname: Simmonds
authors.forename: Veranja
authors.initials: V
authors.lastname: Karunaratne
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000818:Animals; D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D002963:Cladosporium / Q000187:drug effects; D009033:Culicidae / Q000187:drug effects*; D007814:Larva / Q000187:drug effects; D029585:Monimiaceae / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D009032:Mosquito Control; D024301:Plant Bark / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry; D013188:Sri Lanka; D013329:Structure-Activity Relationship
chemical_list: C533546:(4S)-4-methyl-2-(11-dodecenyl)-2-butenolide; C533545:(4S)-4-methyl-2-(11-dodecynyl)-2-butenolide; D000935:Antifungal Agents; C004511:butenolide; D015107:4-Butyrolactone