Galleria mellonella as a novel eco-friendly in vivo approach for the assessment of the toxicity of medicinal plants

Abstract

The evaluation of medicinal plants toxicity is a prerequisite prior their usage. The vertebrate models used for this purpose are often the object of ethical consideration. Though invertebrate models including Galleria mellonella have shown their ability to be used to assess various products toxicity, to our knowledge, G. mellonella has never been exploited to determine the toxicity of medicinal plants. In this study, the toxicity of hydroalcoholic and aqueous extracts of seven (7) Cameroonian medicinal plants namely leaves of Cymbopogon citratus (DC.) Stapf, Moringa oleifera Lam and Vernonia amygdalina Delile; barks of Cinchona officinalis and Enantia chloranta Oliv; barks and seeds of Garcinia lucida Vesque and leaves and seeds of Azadirachta indica (Neem) were evaluated using the larval form of the Greater Wax Moth (Galleria mellonella). The median lethal doses (LD50), 90% lethal doses (LD90) and 100% lethal doses were successfully determined using the spline cubic survival curves and equations from the data obtained on the survival rate of G. mellonella 24h after the injection with the extracts. The LD50 values varied from 3.90 g/kg bw to >166.67 g/kg bw and the pattern of toxicity observed was in accordance with previous investigations on the plant materials concerned. The results obtained in this study suggest that G. mellonella can be used as a sensitive, reliable, and robust eco-friendly model to gauge the toxicity of medicinal plants. Thus, avoid the sacrifice of vertebrate models often used for this purpose to limit ethical concerns.