Topic
Biomphalaria alexandrina
About: Biomphalaria alexandrina is a research topic. Over the lifetime, 413 publications have been published within this topic receiving 3781 citations.
Papers published on a yearly basis
Papers
More filters
•
TL;DR: It is concluded that the byproducts of the blue-green alga Spirulina platensis has a lethal effect against adult B. alexandria snails, reduced or stopped their oviposition, hence minimize the snail populations available for the parasite transmission.
Abstract: Spirulina platensis micro alga has high protein content and nutritional value. It was used for many years as human food and animal feed. It excretes variable quantities of products through its metabolism; some of them have antimicrobial activity. Non-inoculated synthetic medium, culture suspension, cell free culture filtrate, fresh and dry biomass of Spirulina platensis cells were tested for their mollscicidal activity against Biomphalaria alexandrina snails the intermediate host of Schistosoma mansoni in Egypt that accommodates their survival and fecundity. The algal culture filtrate was tested also for its effect on hatchability of snail's eggs and viability of the free living larval stages of the parasite (miracidia and cercariae). The culture filtrate proved to have a lethal effect on snails with 90 LC 0.23% of the filtrate. B. alexandrina snails stopped egg laying after one week of continuous exposure to the sublethal concentrations 0.19 and 0.17%, while those exposed to 0.07% laid few ones. It could be due to the phytochemical constituents of the culture filtrate i.e. total phenolic compounds, alkaloids and total saponins. This was confirmed by histological examination that showed a severe damage in the hermaphrodite gland cells of snails exposed to these concentrations. B. alexandrina eggs of 3 and 7 days old failed to hatch post exposure to 0.1% of algal filtrate, while 22% and 10% only hatched after exposure to 0.05% of this filtrate. Free cell culture filtrate shows also marked miracidicidal and cercaricidal activities as 2% of this filtrate killed most of these organisms within 15 minutes of exposure. It is concluded that the byproducts of the blue-green alga Spirulina platensis has a lethal effect against adult B. alexandria snails, reduced or stopped their oviposition, hence minimize the snail populations available for the parasite transmission. Therefore it may be a potential source of effective compounds for control of Schistosoma mansoni.
14 citations
•
TL;DR: Molluscicidial activity of leaves of Acanthus mollis against Biomphalaria alexandrina were evaluated and petroleum ether extract was more potent than Solanum nigrum and Iris pseudacorus extracts.
Abstract: Molluscicidial activity of leaves of Acanthus mollis against Biomphalaria alexandrina were evaluated. Its petroleum ether extract (LC50 values = 6.92 mg/L) was more potent than Solanum nigrum and Iris pseudacorus extracts. A binary combination (1:1) of A. mollis and S. nigrum, as well as, a binary combination (1:1) of A. mollis and I. pseudacorus extracts showed additive effect on snails (24 hr LC50: 5.09 mg/l and 3.76 mg/l respecttively). A tertiary combination (1:1:1) of A. mollis, S. nigrum and I. pseudacorus extracts (24 hr LC50: 4.01 mg/l) showed good result. Also, petroleum ether extract of A. mollis leaves killed Schistosoma mansoni cercariae at concentrations of 20, 10 and 5 mg/l within 30, 45 min. and an hour respectively. Mortality increased with increasing exposure time and concentration.
14 citations
01 Jan 2011
TL;DR: The histological examinations demonstrated a severe damage in both secretory cells and digestive cells especially in case of Asparagus densiflours and Score and the sublethal concentration LC5 of the three tested agents caused pronounced effect on the alkaline phosphatase (ALP) and acid phosphatases (ACP) activities after the 2 nd weeks of the exposure.
Abstract: In this study, the most effective agent was Difenoconazole (Score) followed by Asparagus densiflours then Oreopanax guatemalensis plants against Biomphalaria alexandrina snails. The high concentrations of the three tested agents caused a remarkable reduction in hatchability percent of B. alexandrina eggs than the low concentrations. The sublethal concentrations (LC10 and LC25) of both A. densiflorus and Score have more destructive effect on the survival, growth and reproductive rates of the juvenile snails than the corresponding concentrations of O. guatemalensis plant. Different sublethal concentrations (LCo and LC5) of the three agents caused a remarkable elevation in the activity of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) enzymes of the snails after the 1 st week of the exposure. The sublethal concentration LC5 of the three tested agents caused pronounced effect on the alkaline phosphatase (ALP) and acid phosphatase (ACP) activities after the 2 nd weeks of the exposure. Total protein, albumin, globulin and albumin/ globulin (A/G) ratio in hemolymph of snails exposed to sublethal concentration LCo of the three tested agents, are differently affected after the 1 st and 2 nd week of the exposure. The histological examinations demonstrated a severe damage in both secretory cells and digestive cells especially in case of Asparagus densiflours and Score.
14 citations
••
TL;DR: The two monodesmosidic saponins 1 and 3 were found to possess strong molluscicidal activity against Biomphalaria alexandrina snails, the intermediate host of Schistosoma mansoni in Egypt.
Abstract: The aqueous methanolic extract of the aerial parts of Fagonia arabica L. (family Zygophyllaceae) was successively fractionated using certain organic solvents. From the ethyl acetate fraction, two flavonoid glycosides were isolated and identified as kaempferol-7-O-rhamnoside and acacetin-7-O-rhamnoside. Four triterpenoidal glycosides were isolated from the butanolic layer. Their structures were elucidated on the basis of the spectral and chemical data as 3-O-beta-D-glucopyranosyl-(1-->3)-alpha-L-arabinopyranoside oleanolic acid (1), 3-O-alpha-L-arabinopyranosyl quinovic acid 28-O-beta-D-glucopyranoside (2), 3-O-[beta-D-glucopyranosyl-(1-->2)]-beta-D-glucopyranosyl-(1-->3)-alpha-L-arabinosyl oleanolic acid (3) and 3-O-beta-D-glucopyranosyl-(1-->3)-alpha-L-arabino-pyranosyl quinovic acid 28-O-beta-D-glucopyranoside (4). The two monodesmosidic saponins 1 and 3 were found to possess strong molluscicidal activity against Biomphalaria alexandrina snails, the intermediate host of Schistosoma mansoni in Egypt (LC90 = 13.33 and 16.44 microM), whereas the other two bidesmosidic saponins 2 and 4 as well as the two flavonoid glycosides were inactive up to 50 microM.
14 citations
•
TL;DR: The results confirm the occurrence of transmission of both Schistosoma mansoni and S. haematobium since infected snails of both species were recovered in these areas, which proves that reclamation of parts of the desert utilizing Nile water had led to spread of schistosomiasis to these areas.
Abstract: The distribution, abundance and seasonality of infected Biomphalaria alexandrina and Bulinus truncatus were studied for 2 years (1992-1994) in two newly reclaimed areas, namely El Manayef and El-Morra areas located on both sides of Suez Canal near Ismailia City. The results confirm the occurrence of transmission of both Schistosoma mansoni and S. haematobium since infected snails of both species were recovered in these areas. This consequently proves that reclamation of parts of the desert utilizing Nile water had led to spread of schistosomiasis to these areas. Analysis of the data shows that the infected snails, especially B. alexandrina, were found clustered in a relatively few numbers of transmission sites and furthermore the greater majority of these sites were found located within a less number of transmission foci. This pattern of focality is clearly demonstrated by Geographical Information System (GIS) produced maps. Infected B. alexandrina snails fluctuated seasonally showing 2 peaks, a minor peak in August and a higher one in November. Only one peak of infected B. truncatus was recognized in July.
13 citations