Toxicity of Five Herbal Extracts against Head Louse (Pediculus Humanus Capitis De Geer.: Phthiraptera) in Vitro

Head lice infestation caused by Pediculus humanus capitis De Geer. (Phthiraptera) is one of the most important public health problem in children worldwide. Currently, head lice resistance to chemical pediculicide are increasing, thus new alternative pediculicides from herb or plant are needed for head lice treatment. The aim of this study were to evaluate toxicity of five herbal extracts from Andrographis paniculata Wall ex Nees (Acanthaceae), Arcangelisia flava (L.) Merr. (Menispermaceae), Butea superba Roxb (Leguminosae), Illicium verum Hook.f. (Illiciaceae) and Nigella sativa Linn. (Ranunculaceae) on mortality of P. humanus capitis at dose of 3 and 6 μl/cm by filter paper method in vitro. The results showed that all herbal extract at 6 μl/cm was more toxic than 3 μl/cm with LT50 values ranged from 0.1 to 21.8 h and 0.6 to 25.2 h, respectively. Moreover, the most toxic was shown by 6 μl/cm of I. verum extract with 100%mortality at 12 h and LC50 value of 0.3 μl/cm , followed by extracts from A. paniculata, N. sativa, B. superba and A. flava with 82.6±6.9, 63.0±7.6, 47.0±9.7 and 32.0±5.7% mortality and LC50 values of 14.2, 20.3, 22.5 and 22.8 μl/cm , respectively. The data pointed that I. verum extract showed high toxic to head lice and showed high potential of pediculicide for head lice control.