摘要
Objective:To assess the molluscicidal and cercariacidal activities of aqueous extracts of Balanites aegyptiaca(B.aegyptiaca)against EthiopianBiomphalaria pfeifferi(B.pfeifferi),Lymnaea natalensis(L.natalensis)and Schistosoma mansoni(S.mansoni)cercariae.Methods:Extracts of seeds,endocarp,mesocarp,and fruit of B.aegyptiacawere tested for their activities against adultB.pfeifferiandL.natalensis.The cercariacidal activity of the seeds of the plant was also evaluated againstS.mansoni.Bioassays were carried out following the methods recommended by WHO.Snail mortalities were compared between each plant part and snail species,and LC50and LC90values for the plant parts tested were computed.The cercariacidal activity of the plant was assessed by exposing the mice to the cercariae pre-exposed to aqueous extract of B.aegyptiacaseeds.Results:For the molluscicidal activities of seeds,endocarp,mesocarp and whole fruit,the LC50values againstB.pfeifferiwere 56.32,77.53,65.51 and 66.63 mg/L,respectively,while the respective LC90values were 77.70,120.04,89.50 and 97.55 mg/L.Similarly,the LC50values for the seeds,endocarp,mesocarp and whole fruit againstL.natalensiswere 80.33,92.61,83.52 and 87.84mg/L,respectively,while the respective LC90values were 102.30,138.21,115.42 and 127.69 mg/L.B.pfeifferiwere found to be more susceptible toB.aegyptiacathanL.natalensis.S.mansoni cercariae exposed to 15 mg/L of extract of seeds were incapable of infecting mice.The mean egg load of tissue was reduced in mice infected with the cercariae exposed to 5 and 10 mg/L of the extract.Conclusions:The aqueous extracts of different parts ofB.aegyptiacaexhibited reasonable molluscicidal activity againstB.pfeifferiandL.natalensis,as well as cercariacidal activity againstS.mansonicercariae.However,comprehensive laboratory evaluation is recommended prior to field tests of the plant parts since their impact on other aquatic biota is not known.
Objective:To assess the molluscicidal and cercariacidal activities of aqueous extracts of Balanites aegyptiaca(B.aegyptiaca)against EthiopianBiomphalaria pfeifferi(B.pfeifferi),Lymnaea natalensis(L.natalensis)and Schistosoma mansoni(S.mansoni)cercariae.Methods:Extracts of seeds,endocarp,mesocarp,and fruit of B.aegyptiacawere tested for their activities against adultB.pfeifferiandL.natalensis.The cercariacidal activity of the seeds of the plant was also evaluated againstS.mansoni.Bioassays were carried out following the methods recommended by WHO.Snail mortalities were compared between each plant part and snail species,and LC50and LC90values for the plant parts tested were computed.The cercariacidal activity of the plant was assessed by exposing the mice to the cercariae pre-exposed to aqueous extract of B.aegyptiacaseeds.Results:For the molluscicidal activities of seeds,endocarp,mesocarp and whole fruit,the LC50values againstB.pfeifferiwere 56.32,77.53,65.51 and 66.63 mg/L,respectively,while the respective LC90values were 77.70,120.04,89.50 and 97.55 mg/L.Similarly,the LC50values for the seeds,endocarp,mesocarp and whole fruit againstL.natalensiswere 80.33,92.61,83.52 and 87.84mg/L,respectively,while the respective LC90values were 102.30,138.21,115.42 and 127.69 mg/L.B.pfeifferiwere found to be more susceptible toB.aegyptiacathanL.natalensis.S.mansoni cercariae exposed to 15 mg/L of extract of seeds were incapable of infecting mice.The mean egg load of tissue was reduced in mice infected with the cercariae exposed to 5 and 10 mg/L of the extract.Conclusions:The aqueous extracts of different parts ofB.aegyptiacaexhibited reasonable molluscicidal activity againstB.pfeifferiandL.natalensis,as well as cercariacidal activity againstS.mansonicercariae.However,comprehensive laboratory evaluation is recommended prior to field tests of the plant parts since their impact on other aquatic biota is not known.
基金
Financially supported by School of Graduate Studies,Addis Ababa University(Grant No.GSR/2830/02)
