In vitro molluscicidal activity of wormwood (Artemisia dubia) leaves against Oncomelania hupensis quadrasi


Author(s): Charles Jardian C. Alinsub and Melvin A. Bagot*

Abstract

There have been many efforts to eradicate the problem of schistosomiasis. One method is to control the growing snail population. This study aimed to determine the molluscicidal activity of wormwood (Artemisia dubia)leaves methanolic extract against adult and juvenile. Using infusion technique, 80% methanol was used as solvent. There were eight treatments used: distilled water (T0(-)1) and 1% methanol (T0(-)2) as negative controls; 0.0002% (2mg/L) niclosamide (T0(+)) as positive control; and 11.121% (T1), 12.478% (T2), 14% (T3), 15.708% (T4) and 17.625% (T5), which were replicated five times with 10 snails per replicate.
Results showed that for adults, the wormwood leaves methanolic extract was not statistically significant with the commercially available molluscicide, although 17.625% (T5) resulted in 82% mortality rate. For juveniles, the different extract concentrations resulted in 98 to 100% mortality, which were comparable to 0.0002% (2mg/L) niclosamide and were considered highly effective based on Reik & Keitz (1954) and European Agency for the Evaluation of Medicinal Products (EMEA). Thus, wormwood leaves methanolic extract has a promising molluscicidal activity against adult snails at a concentration of 17.625%, and at all concentrations for the juvenile snails of O. hupensis quadrasi. The LC50 of the adult and juvenile snails were 14.075% and 10.294%, respectively.
Secondary metabolites that were found positive during the qualitative phytochemical analysis with the extract were tannins, saponins, and terpenoids. The mortality of the snails can be attributed to the bioactivity of the secondary metabolites present that may be acting in combination or individually.

Keywords : Artemisia dubia, wormwood, Oncomelania hupensis quadrasi, molluscicide