Browsing by Author "Ndiege, IO"

Now showing 1 - 5 of 5
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    PublicationOpen Access
    Anti-plasmodial activity of some Kenyan medicinal plant extracts singly and in combination with chloroquine.
    (Phytother Res., 2004-05) Muregi, Francis W.; Chhabra, S. C.; Njagi, EN; Thoruwa, Lang'at CC; Njue, WM; Orago, AS; Omar, SA; Ndiege, IO
    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 < or = 100 microg/mL). Extracts of four plants, Ekebergia capensis, Stephania abyssinica, Ajuga remota and Clerodendrum myricoides gave IC50 values below 30 microg/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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    PublicationOpen Access
    Anti-plasmodial activity of some Kenyan medicinal plant extracts singly and in combination with chloroquine.
    (Mount Kenya University, 2004-05) Muregi, FW; Chhabra, SC; Njagi, EN; Lang'at, Thoruwa CC; Njue, WM; Orago, AS; Omar, SA; Ndiege, IO
    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 < or = 100 microg/mL). Extracts of four plants, Ekebergia capensis, Stephania abyssinica, Ajuga remota and Clerodendrum myricoides gave IC50 values below 30 microg/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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    PublicationOpen Access
    The in vitro anti-plasmodial and in vivo anti-malarial efficacy of combinations of some medicinal plants used traditionally for treatment of malaria by the Meru community in Kenya
    (J Ethnopharmacol, 2008-01-17) Gathirwa, JW; Rukunga, GM; Njagi, EN; Omar, SA; Mwitari, PG; Guantai, AN; Tolo, FM; Kimani, CW; Muthaura, CN; Kirira, PG; Ndunda, TN; Amalemba, G; Mungai, GM; Ndiege, IO
    The use of herbal drugs as combinations has existed for centuries in several cultural systems. However, the safety and efficacy of such combinations have not been validated. In this study, the toxicity, anti-plasmodial and antimalarial efficacy of several herbal drug combinations were investigated. Lannea schweinfurthii, Turraea robusta and Sclerocarya birrea, used by traditional health practitioners in Meru community, were tested for in vitro anti-plasmodial and in vivo anti-malarial activity singly against Plasmodium falciparum and Plasmodium berghei, respectively. Methanolic extract of Turraea robusta was the most active against Plasmodium falciparum D6 strain. Aqueous extracts of Lannea schweinfurthii had the highest anti-plamodial activity followed by Turraea robusta and Sclerocarya birrea. D6 was more sensitive to the plant extracts than W2 strain. Lannea schweinfurthii extracts had the highest anti-malarial activity in mice followed by Turraea robusta and Sclerocarya birrea with the methanol extracts being more active than aqueous ones. Combinations of aqueous extracts of the three plants and two others (Boscia salicifolia and Rhus natalensis) previously shown to exhibit anti-plasmodial and anti-malarial activity singly were tested in mice. Marked synergy and additive interactions were observed when combinations of the drugs were assayed in vitro. Different combinations of Turraea robusta and Lannea schweinfurthii exhibited good in vitro synergistic interactions. Combinations of Boscia salicifolia and Sclerocarya birrea; Rhus natalensis and Turraea robusta; Rhus natalensis and Boscia salicifolia; Turraea robusta and Sclerocarya birrea; and Lannea schweinfurthii and Boscia salicifolia exhibited high malaria parasite suppression (chemo-suppression >90%) in vivo when tested in mice. The findings are a preliminary demonstration of the usefulness of combining several plants in herbal drugs, as a normal practice of traditional health practitioners.
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    PublicationOpen Access
    In vitro antiplasmodial activity of some plants used in Kisii, Kenya against malaria and their chloroquine potentiation effects.
    (Mount Kenya University, 2003-02) Muregi, FW; Chhabra, EN; Lang'at, Thoruwa CC; Nijue, WM; Orago, AS; Omar, AS; Ndiege, IO
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    PublicationOpen Access
    In vitro antiplasmodial activity of some plants used in Kisii, Kenya against malaria and their chloroquine potentiation effects.
    (J Ethnopharmacol, 2003-02) Muregi, FW; Chhabra, sc; Njagi, EN; Thoruwa, Lang'at; Njue, WM; Orago, AS; Omar, SA; Ndiege, IO
    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.