The Killing Effects of Thai Medicinal Plants against Parasitic Helminths

Abstract

Abstract

The killing effects of three Thai medicinal plants–depree (Piper retrofractum), black pepper (Piper nigrum), and Areca nut (Areca catechu)–were tested against parasitic helminths in vitro and in vivo. These herbs had the ability to kill the eggs of intestinal helminths, the infective larvae of hookworms and Strongyloides stercoralis in vitro, and adult-stage hookworms in vivo. Against hookworm eggs, the lethal concentrations of depree, black pepper, and Areca nut, were 6.5, 45.0, and 6.0 mg, respectively. The lethal concentration of depree against infective hookworm larvae was 448.7 mg and black pepper 165.0 mg, while the lethal concentration against S. stercoralis was 15.0 mg. A single, 1-g oral dose of depree gave a 20% cure rate, and an 80-90% egg-reduction rate, among hookworm-infected dogs.

Keywords : herb, helminth, egg, larva, adult, in vitro, in vivo