Browsing by Author "Chhabra, S.C."

Now showing 1 - 6 of 6
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    Anti-plasmodial Activity of Some Kenyan Medicinal Plant Extracts Singly and in Combination with Chloroquine
    (Wiley InterScience, 2004) Muregi, F.W.; Chhabra, S.C.; Njagi, Eliud N.; Lang’at, C.; Njue, Wilson N.; Orago, A.S.; Omar, S.A.; Ndiege, I.O.
    Sixty organic and aqueous extracts of eleven plants used for the control of malaria by local communities in Kisii District, Kenya were screened for in vitro anti-plasmodial activity. The plants selection was based on existing ethnobotanical information and interviews with local communities. The extracts were tested against chloroquine sensitive and resistant laboratory adapted strains of Plasmodium falciparum. The study revealed that 63.6% of the plants were active (IC50 ≤ 100 μg/mL). Extracts of four plants, Ekebergia capensis, Stephania abyssinica, Ajuga remota and Clerodendrum myricoides gave IC50 values below 30 μg/mL against both chloroquine sensitive and resistant P. falciparum strains. Combination of extracts of E. capensis and C. myricoides with chloroquine against the multi-drug resistant P. falciparum isolate (V1/S) revealed synergistic effect. The plants which showed activity may be useful as sources for novel anti-plasmodial compounds.
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    Bioactive steroidal alkaloid glycosides from Selanum aculeastrum.
    (2002) Wanyonyi, Alphonse W.; Chhabra, S.C.; Mkoji, G.; Eilert, Udo; Njue, Wilson N.
    Solanum aculeastrum Dunal was investigated for the presence of molluscicidal compounds. This led to the isolation of solaculine A, from the root bark in addition to known steroidal alkaloids; solamargine and beta-solamarine from the berries. The structures were elucidated by spectroscopic techniques. Molluscicidal activity of the aqueous extracts of the berries and root bark, and the isolated compounds were investigated.
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    Heavy Metals and Pesticides in Marine Sediment, Seawater, and Seaplants Along the Kenya-Mombasa Coastline
    (Taylor & Francis, 2003) Oyugi, Mildred P.; Chhabra, S.C.; Njue, Wilson N.; Kinyua, Anthony M.
    Marine sediment, seawater and several species of seaplants along the Kenya- Mombasa coastal region were analyzed to determine the levels of heavy metals by AAS and EDXRF and organochlorine pesticides (OCPs) by GLC-ECD. In marine sediments, there were high levels of manganese (1100 mg/L) at Vanga, compared to other study sites. In seawater, the heavy metals were detected in levels higher than those considered as natural in the ocean and the range was 0.01–0.30 mg/L. OCPs were detected in marine sediments and in seaplants. The trend of concentration of these pollutants in ascending order in seawater, marine sediment and seaplants was observed.
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    In vitro antiplasmodial activity of some plants used in Kisii, Kenya against Malaria and their chloroquine potentiative effects.
    (2003) Muregi, F.W.; Chhabra, S.C.; Njagi, Eliud N.; Lang’at-Thoruwa, C.; Njue, Wilson N.; Ndiege, I.O.
    Fifty-five organic and aqueous extracts of 11 plants used in malaria therapy in Kisii District, Kenya were tested in vitro against chloroquine (CQ)-sensitive and resistant strains of Plasmodium falciparum. Of the plants tested, 73% were active (IC(50) < 100 microg/ml). Three plants, Vernonia lasiopus, Rhamnus prinoides and Ficus sur afforded extracts with IC(50) values ranging less than 30 microg/ml against both CQ-sensitive and resistant strains. Combination of some extracts with CQ against the multi-drug resistant P. falciparum isolate V1/S revealed some synergistic effect. The plant extracts with low IC(50) values may be used as sources for novel antimalarial compounds to be used alone or in combination with CQ.
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    molluscicidal and antimicrobial activity of solanum aculeastrum
    (2003) Wanyonyi, Alphonse W.; Chhabra, S.C.; Mkojo, G.; Njue, Wilson N.; Tarus, Paul K.
    The methanolic extract of the fresh root bark and berries of Solanum aculeastrum showed significant activity against host snails of schistosomiasis. The berries extract was more potent with 100% snail kill at 50 ppm. Fractionation increased activity with 100% mortality at 20 ppm. The aqueous and methanolic extracts of the berries showed moderate antimicrobial activity, increasing by fractionation.
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    Organo-chlorine residues in tissues of marine fauna along the coast of Kenya Mombasa Island
    (2007) Bor, S.K.; Simbauni, J.A.; Oyugi, Mildred P.; Njue, Wilson N.; Chhabra, S.C.
    Soft tissues of species of marine fauna; crabs (Crust acea ), oysters ( Pelecypoda, Bivalvia), sea stars ( Asterroidea ), sea urchin (Echinoidea) and bony fishes (Osteichtyes) sampled along the Kenya - Mombasa coastal region were analyzed to determine the levels of organochlorine pesticides (OCPs). Analysis was done using gas chromatography with an electron capture detector. This study showed that marine fauna accumulated some OCPs in their tissues, 1,2,3,4,5,6 - hexachlorocyclohexane (BHC) being the most common of the OCPs. These findings highlight evidence of pollution of marine fauna at the Kenyan coastal sites. It is necessary to have thorough waste management programs as a strategy to minimize marine pollution