Molluscicidal and larvicidal activities and essential oil composition of Cymbopogon winterianus

CONTEXT. Cymbopogon winterianus Jowitt ex Bor (Poaceae), known as citronella grass, is an aromatic herbaceous plant and the essential oil extracted from this grass is used in cosmetics, perfumes, hygiene and cleanliness products worldwide.

This study investigated the composition and molluscicidal and larvicidal activities of the essential oil of C. winterianus cultivated in North Brazil.

The oil was obtained by hydrodistillation, analyzed by gas chromatography (GC) and GC-mass spectrometry and then its molluscicidal and larvicidal activities against snails (Biomphalaria glabrata) and hatched larvae of Artemia salina, respectively, were evaluated at concentrations from 10 to 1000 mg/L.

The main constituents of oil were citronellal (26.5%), geraniol (16.2%), elemol (14.5%) and citronellol (7.3%). The molluscicidal test revealed significant lethal concentration (LC) values (LC90=97.0 mg/L, LC50=54.0 mg/L and LC20=22.0 mg/L), indicating the presence of molluscicidal compounds in the oil. In addition, the oil showed moderate larvicidal activity (LC50=181.0 mg/L) against the larvae of A. salina, which could justify its use in the aquatic environment without affecting other living organisms.

The results suggest that the oil of C. winterianus could be an effective alternative to control schistosomiasis, with an average margin of safety to other living organisms that coexist with snails.