Effects of varying concentrations of the crude aqueous and ethanolic extracts of <i>Dalbergia sissoo</i> plant parts on <i>Biomphalaria pfeifferi</i> egg masses.

Abstract

This study evaluated, using replicated laboratory bioassays, the toxicities of the crude aqueous and ethanolic extracts of Dalbergia sissoo Roxb. 1832 (family Leguminosae) fruits, leaves, roots and stem bark against egg masses of Biomphalaria pfeifferi (Krauss, 1848), the snail intermediate host of Schistosoma mansoni (Sambon, 1907) in Nigeria. Viable 0-24 hr-old embryonated egg masses were separately exposed to five different concentrations (7.81-2000 mg/l) of extracts for 24 hrs, washed in dechlorinated tap water and incubated at room temperature for a maximum of 4 weeks. The LC 50 and LC 90 values of test extracts for egg masses were calculated by probit analysis. The activities of the tested extracts were concentration-dependent. However, only the ethanolic extract of the fruits demonstrated significant activity (24 hr-LC 90 value < 100 mg/l: 89.29 mg/l). Mortalities of eggs were manifested at the gastrula/exogastrula and or the prehatch snail stage of development. The percentage of dead embryos at the prehatch snail stage decreased while the deaths of embryos at the gastrula/exogastrula stage increased, with increasing concentration of extract. Lethality of the ethanolic extract of D. sissoo fruits to embryonated egg masses of B. pfeifferi is an added advantage to its potential development for use as a plant molluscicide, as the overall efficacy of a molluscicide is greatly enhanced if it also shows significant toxicity towards snail eggs.

Molluscicidal activities of curcumin-nisin polylactic acid nanoparticle on Biomphalaria pfeifferi

“…Intensive studies have been conducted in search of agents which are more environmentally friendly to combat the intermediate hosts of Schistosoma . Efforts are directed particularly towards molluscicides of plant origin with several studies reported across the world [ 5 – 11 ]. Nevertheless, there is currently no licensed plant-derived molluscicide despite this myriad of studies.…”

Efficacy of Achyranthes aspera (L.) as a Molluscicidal Bait Formulation against Fresh Water Snail Biomphalaria pfeifferi

“…Mature green leaves were collected in October 2016 from a natural habitat located at 9°43′45.59′′ N, 39°73′2.71′′ E, central Ethiopia. It was dried in the shade and ground to fine powder of 200 μ m mesh size as in Adenusi and Odaibo [ 21 ]. It was stored in plastic bags in the laboratory of Environmental Health Science and Technology, Jimma University, Ethiopia.…”

In vitro assessment of Schistosoma mansoni cercaricidal activities of Solanum nigrum and Callistemon citrinius leaves extracts and cercarial genetic changes by RAPD-PCR

“…Out of these 38 bands, 12 were monomorphic (shared among all groups) and 26 bands were polymorphic (Table 3). Data in table (4) revealed that cercariae exposed to S. nigrum (Group B) revealed a higher number (20) of polymorphic bands, and C. citrinus (Group C) revealed 16 bands which were different from those of control group either by presence or absence.…”

“…Different weights of both plant extracts were dissolved in one ml dimethylsulfoxide (DMSO) then diluted by dechlorinated water [20] . The concentrations obtained for S. nigrum were 15 mg/L, 20 mg/L, 25 mg/L and 50 mg/L (21) , and for C. citrinus they were 20 mg/L, 30 mg/L, 40 mg/L and 60 mg/L [22] .…”