TOXICITY OF KHAYA GRANDIFOLIOLA (AFRICAN MAHOGANY) BARK WATER EXTRACT AGANIST BIOMOPHLARIA SNAILS

MAKKI, M.A*, Elkhidir, M. E.**, Madani, M. E***

MAKKI, M.A*, Elkhidir, M. E.**, Madani, M. E*** * Military Hospital Gabal Awalia. Khartoum Sudan ** Department of Epidemiology, Faculty of Public and Environmental Health, University of Khartoum. ***Department of Parasitology, Faculty of Medical Laboratory Sciences, Alneelain University, Khartoum, Sudan.

Abstract

Background: Molluscicides are crucial for the control of schistosomiasis and other snail-borne infections. The need to use plant s has received increased interest as an inexpensive technology because of the high cost of synthetic compounds for snail control in the endemic areas of poor nations of the world. The aim of this study was to investigate the toxic effect of the aqueous extract of Khaya grandifoliola “Mahogany” bark against Biomphalaria snails under laboratory conditions.

Methods: A true experimental study was done to find out the toxic effect of the aqueous extract of Mahogany bark on Biomphalaria snails. An aqueous extract from bark was powdered and strained and was used as stock solution. Serial concentrations of 0.0005% up to 0.01% were tested on Biomphalaria snails. The snails were subjected to the extract for 24hrs. After that the Lc50 and Lc90 were obtained and the toxic index was compared to that of the classical molluscicide “Baylucide” was also obtained.

Results: The mortality rate was found to be ranging between 13% and 87%. Three trials were made and the average was taken. The LC50 and LC90 were found to be 0.015% and 0.039% consecutively. The toxic index compared to baylucide was found to be 75%)

Discussion: Niclosamide, the active ingredient of baylucide is the classical pesticide for snail control (12). Because of its impacts on other aquatic fauna and the environment, quest for safer pesticides has attracted researchers to look into plants with pesticidal properties. Khaya grandifoliola “Mahogany” proved to be one of those plants. The aqueous extract of this tree has been found to be potent in controlling Biomphalaria snails. It is recommended to do more research on the plant extracts in water and other solvents. Yet, since the chemical contents of plants depend mainly on soil composition, it is of paramount importance to test extracts of “Mahogany” from different geographical areas.