Selected α-pyrones from the plants Cryptocarya novoguineensis (Lauraceae) and Piper methysticum (Piperaceae) with activity against Haemonchus contortus in vitro

Publication date: Available online 4 January 2019Source: International Journal for Parasitology: Drugs and Drug ResistanceAuthor(s): H.M.P. Dilrukshi Herath, Sarah Preston, Abdul Jabbar, Jose Garcia-Bustos, Russell S. Addison, Sasha Hayes, Topul Rali, Tao Wang, Anson V. Koehler, Bill C.H. Chang, Andreas Hofmann, Rohan A. Davis, Robin B. GasserAbstractDue to the widespread occurrence and spread of anthelmintic resistance, there is a need to develop new drugs against resistant parasitic nematodes of livestock animals. The Nobel Prize-winning discovery and development of the anti-parasitic drugs avermectin and artemisinin has renewed the interest in exploring natural products as anthelmintics. In the present study, we screened 7500 plant extracts for in vitro-activity against the barber's pole worm, Haemonchus contortus, a highly significant pathogen of ruminants. The anthelmintic extracts from two plants, Cryptocarya novoguineensis and Piper methysticum, were fractionated by high-performance liquid chromatography (HPLC). Subsequently, compounds were purified from fractions with significant biological activity. Four α-pyrones, namely goniothalamin (GNT), dihydrokavain (DHK), desmethoxyyangonin (DMY) and yangonin (YGN), were purified from fractions from the two plants, GNT from C. novoguineensis, and DHK, DMY and YGN (= kavalactones) from P. methysticum. The three kavalactones induced a lethal, eviscerated (Evi) phenotype in treated exsheathed third-stage larvae (xL3s), and DMY ...
Source: International Journal for Parasitology: Drugs and Drug Resistance - Category: Parasitology Source Type: research