In attempt to investigate some biological activities of Mammea usambarensis fruit, absolute ethan... more In attempt to investigate some biological activities of Mammea usambarensis fruit, absolute ethanolic crude extract, 80% DCM/PE fraction, 5% MeOH/DCM fraction and mammea B/AB were subjected to toxicity test in brine shrimps and mice, antimicrobial activity by disc diffusion and broth dilution method and antioxidant activity by DPPH scavenging activity. In the brine shrimps toxicity test, the crude extract, 80% DCM/PE fraction, 5% MeOH/DCM fraction and mammea B/AB were highly toxic with LC 50 values of 1.58, 1.14, 3.89 and 5.21 µg/ml, respectively. The crude extract was non-toxic to mice even at a dose above 2000 mg/kg body weight. The crude extract, 80% DCM/PE 5% MeOH/DCM fractions and mammea B/AB exhibited low activity with zone of inhibition of 8.3-16 mm for Salmonella kisarawe, 8.7-14 mm for Staphylococcus aureus and 8.3-10 mm for Klebsiella oxytoca. The minimum inhibitory concentrations ranged from 3.75 µg/µl-25 µg/µl. All samples tested had no activity against Candida albicans ...
This in vivo study aimed to compare hypoglycaemic activity of three commonly medicinal plants use... more This in vivo study aimed to compare hypoglycaemic activity of three commonly medicinal plants used traditionally for diabetes management in northern Tanzania Artemisia afra Willd. (Aerial parts), Moringaoleifera Lam. (Leaves) and Perseaamericana Mill. (Leaves).Evaluation for hypoglycaemic activity of 80% aqueous ethanol plant extracts was conducted at a dose of 200 mg/kg body weight, orally in glucose loaded normal white albino mice by using Oral Glucose Tolerance Test (OGTT) method. The statistical analysis of results was carried out by using Student t-test followed by one-way Analysis of variance (ANOVA) and Tukey’s multiple comparisons at probability value (p˂ 0.05).Phytochemical evaluation focused on the normal reactions of characterization based on precipitation and coloration with standard reagents. At a dose of 200 mg/kg bw.t, the three plants showed significant hypoglycaemic activity by lowering blood glucose level in glucose loaded normal white albino mice at a rate of 23%,...
The East and Central African Journal of Pharmaceutical Sciences, 2011
The 80% aqueous ethanol extract of Croton macrostachys A. Rich (Euphorbiaceae) roots and the six ... more The 80% aqueous ethanol extract of Croton macrostachys A. Rich (Euphorbiaceae) roots and the six isolated compounds were tested for oral glucose tolerance test, antibacterial activity and brine shrimp lethality test. The 80% aqueous ethanol extract significantly escalated postprandial blood glucose levels (P ≤ 0.05) in mice. The extract also exhibited a weak antibacterial activity against some Gram-positive and Gram-negative bacteria and a weak antifungal activity against Candida albicans. Among the six isolated compounds, one compound significantly elevated postprandial blood glucose (P≤0.05), while two compounds exhibited a weak antibacterial activity, but none exhibited antifungal activity. The crude extract and compounds were both cytotoxic to brine shrimps.
Kotschya plant species have been shown to be potential larvicides against Culex quinquefasciatus ... more Kotschya plant species have been shown to be potential larvicides against Culex quinquefasciatus and Anopheles gambiae species. Isolation of compounds from larvicidal crude extracts of selected four Kotschya plant species namely K. uguenensis, K. strigosa, K. speciosa and K thymodora yielded cycloartenone (1) as the major compound. The presence of this compound in the four species was confirmed by detailed spectroscopic methods and the already published data. Quantitative analysis of cycloartenone (1) in the four species collected during wet and dry seasons was compared. Findings indicated higher yields during wet seasons ranging from 68 x 10-2 to 120 x 10-2 mg/ml than dry seasons which revealed amounts ranging from 0 to 150 x 10-2 mg/ml. However, the highest amount of cycloartenone (1) was present in the stem barks of K. uguenensis for the dry season whereas the 120 x 102 mg/ml was observed in the aerial parts of K. strigosa collected during wet season. Cycloartenone (1) is being i...
The medicinal plants have been used traditionally for different purposes such as pest control and... more The medicinal plants have been used traditionally for different purposes such as pest control and treatment of human diseases. Despite these potentials, only few plants have been evaluated for their safety. This study aimed at investigating oral acute toxicity of Annona squamosa leaf extract and fractions using albino mice. The aqueous-ethanol, dichloromethane and petroleum ether fractions were prepared and tested for oral acute toxicity. Whereas some toxicity signs occurred for aqueous-ethanol extract at doses ≥1500 mg/kg bwt that of dichloromethane fraction were seen at 1000-5000 mg/kg and that of petroleum ether fraction were at 5000 mg/kg. All the tested materials at a dose above 300 mg/kg bwt had negative effects on the growth of the mice. The LD 50 were estimated to be >1000 mg/kg bwt for dichloromethane, >1500 mg/kg bwt for aqueous-ethanol extract and >3000 mg/kg bwt for petroleum ether fraction. All mice dissected had normal organs except one among six females treat...
The medicinal plants have been used traditionally for different purposes such as pest control and... more The medicinal plants have been used traditionally for different purposes such as pest control and treatment of human diseases. Despite these potentials, only few plants have been evaluated for their safety. This study aimed at investigating oral acute toxicity of Annona squamosa leaf extract and fractions using albino mice. The aqueous-ethanol, dichloromethane and petroleum ether fractions were prepared and tested for oral acute toxicity. Whereas some toxicity signs occurred for aqueous-ethanol extract at doses ≥1500 mg/kg bwt that of dichloromethane fraction were seen at 1000-5000 mg/kg and that of petroleum ether fraction were at 5000 mg/kg. All the tested materials at a dose above 300 mg/kg bwt had negative effects on the growth of the mice. The LD50 were estimated to be >1000 mg/kg bwt for dichloromethane, >1500 mg/kg bwt for aqueous-ethanol extract and >3000 mg/kg bwt for petroleum ether fraction. All mice dissected had normal organs except one among six females treate...
HIV-1 resistance is one of the problems affecting success of antiretroviral therapy programmes wo... more HIV-1 resistance is one of the problems affecting success of antiretroviral therapy programmes worldwide. Many studies on efficacy of ART programmes, specifically on drug resistance, have been conducted in developed countries but not in developing countries due to lack of resources. So many tests have been optimized for HIV-1 subtype B which is prevalent in the developed countries but not for non-subtype B which is the main HIV-1 subtype in developing world. Some few studies have been conducted in Tanzania to evaluate the efficacy of the ART regimens and programmes. These studies have evaluated either the virological efficacy and genotypic resistance in patients receiving ART (to evaluate development of acquired resistance) or genotypic resistance in drug naive patients (to assess primary resistance). These few studies have been conducted in cities or urban areas with referral hospitals and have indeed shown some degree of resistance to ART and have provided some insights into degre...
In attempt to investigate some biological activities of Mammea usambarensis fruit, absolute ethan... more In attempt to investigate some biological activities of Mammea usambarensis fruit, absolute ethanolic crude extract, 80% DCM/PE fraction, 5% MeOH/DCM fraction and mammea B/AB were subjected to toxicity test in brine shrimps and mice, antimicrobial activity by disc diffusion and broth dilution method and antioxidant activity by DPPH scavenging activity. In the brine shrimps toxicity test, the crude extract, 80% DCM/PE fraction, 5% MeOH/DCM fraction and mammea B/AB were highly toxic with LC 50 values of 1.58, 1.14, 3.89 and 5.21 µg/ml, respectively. The crude extract was non-toxic to mice even at a dose above 2000 mg/kg body weight. The crude extract, 80% DCM/PE 5% MeOH/DCM fractions and mammea B/AB exhibited low activity with zone of inhibition of 8.3-16 mm for Salmonella kisarawe, 8.7-14 mm for Staphylococcus aureus and 8.3-10 mm for Klebsiella oxytoca. The minimum inhibitory concentrations ranged from 3.75 µg/µl-25 µg/µl. All samples tested had no activity against Candida albicans ...
This in vivo study aimed to compare hypoglycaemic activity of three commonly medicinal plants use... more This in vivo study aimed to compare hypoglycaemic activity of three commonly medicinal plants used traditionally for diabetes management in northern Tanzania Artemisia afra Willd. (Aerial parts), Moringaoleifera Lam. (Leaves) and Perseaamericana Mill. (Leaves).Evaluation for hypoglycaemic activity of 80% aqueous ethanol plant extracts was conducted at a dose of 200 mg/kg body weight, orally in glucose loaded normal white albino mice by using Oral Glucose Tolerance Test (OGTT) method. The statistical analysis of results was carried out by using Student t-test followed by one-way Analysis of variance (ANOVA) and Tukey’s multiple comparisons at probability value (p˂ 0.05).Phytochemical evaluation focused on the normal reactions of characterization based on precipitation and coloration with standard reagents. At a dose of 200 mg/kg bw.t, the three plants showed significant hypoglycaemic activity by lowering blood glucose level in glucose loaded normal white albino mice at a rate of 23%,...
The East and Central African Journal of Pharmaceutical Sciences, 2011
The 80% aqueous ethanol extract of Croton macrostachys A. Rich (Euphorbiaceae) roots and the six ... more The 80% aqueous ethanol extract of Croton macrostachys A. Rich (Euphorbiaceae) roots and the six isolated compounds were tested for oral glucose tolerance test, antibacterial activity and brine shrimp lethality test. The 80% aqueous ethanol extract significantly escalated postprandial blood glucose levels (P ≤ 0.05) in mice. The extract also exhibited a weak antibacterial activity against some Gram-positive and Gram-negative bacteria and a weak antifungal activity against Candida albicans. Among the six isolated compounds, one compound significantly elevated postprandial blood glucose (P≤0.05), while two compounds exhibited a weak antibacterial activity, but none exhibited antifungal activity. The crude extract and compounds were both cytotoxic to brine shrimps.
Kotschya plant species have been shown to be potential larvicides against Culex quinquefasciatus ... more Kotschya plant species have been shown to be potential larvicides against Culex quinquefasciatus and Anopheles gambiae species. Isolation of compounds from larvicidal crude extracts of selected four Kotschya plant species namely K. uguenensis, K. strigosa, K. speciosa and K thymodora yielded cycloartenone (1) as the major compound. The presence of this compound in the four species was confirmed by detailed spectroscopic methods and the already published data. Quantitative analysis of cycloartenone (1) in the four species collected during wet and dry seasons was compared. Findings indicated higher yields during wet seasons ranging from 68 x 10-2 to 120 x 10-2 mg/ml than dry seasons which revealed amounts ranging from 0 to 150 x 10-2 mg/ml. However, the highest amount of cycloartenone (1) was present in the stem barks of K. uguenensis for the dry season whereas the 120 x 102 mg/ml was observed in the aerial parts of K. strigosa collected during wet season. Cycloartenone (1) is being i...
The medicinal plants have been used traditionally for different purposes such as pest control and... more The medicinal plants have been used traditionally for different purposes such as pest control and treatment of human diseases. Despite these potentials, only few plants have been evaluated for their safety. This study aimed at investigating oral acute toxicity of Annona squamosa leaf extract and fractions using albino mice. The aqueous-ethanol, dichloromethane and petroleum ether fractions were prepared and tested for oral acute toxicity. Whereas some toxicity signs occurred for aqueous-ethanol extract at doses ≥1500 mg/kg bwt that of dichloromethane fraction were seen at 1000-5000 mg/kg and that of petroleum ether fraction were at 5000 mg/kg. All the tested materials at a dose above 300 mg/kg bwt had negative effects on the growth of the mice. The LD 50 were estimated to be >1000 mg/kg bwt for dichloromethane, >1500 mg/kg bwt for aqueous-ethanol extract and >3000 mg/kg bwt for petroleum ether fraction. All mice dissected had normal organs except one among six females treat...
The medicinal plants have been used traditionally for different purposes such as pest control and... more The medicinal plants have been used traditionally for different purposes such as pest control and treatment of human diseases. Despite these potentials, only few plants have been evaluated for their safety. This study aimed at investigating oral acute toxicity of Annona squamosa leaf extract and fractions using albino mice. The aqueous-ethanol, dichloromethane and petroleum ether fractions were prepared and tested for oral acute toxicity. Whereas some toxicity signs occurred for aqueous-ethanol extract at doses ≥1500 mg/kg bwt that of dichloromethane fraction were seen at 1000-5000 mg/kg and that of petroleum ether fraction were at 5000 mg/kg. All the tested materials at a dose above 300 mg/kg bwt had negative effects on the growth of the mice. The LD50 were estimated to be >1000 mg/kg bwt for dichloromethane, >1500 mg/kg bwt for aqueous-ethanol extract and >3000 mg/kg bwt for petroleum ether fraction. All mice dissected had normal organs except one among six females treate...
HIV-1 resistance is one of the problems affecting success of antiretroviral therapy programmes wo... more HIV-1 resistance is one of the problems affecting success of antiretroviral therapy programmes worldwide. Many studies on efficacy of ART programmes, specifically on drug resistance, have been conducted in developed countries but not in developing countries due to lack of resources. So many tests have been optimized for HIV-1 subtype B which is prevalent in the developed countries but not for non-subtype B which is the main HIV-1 subtype in developing world. Some few studies have been conducted in Tanzania to evaluate the efficacy of the ART regimens and programmes. These studies have evaluated either the virological efficacy and genotypic resistance in patients receiving ART (to evaluate development of acquired resistance) or genotypic resistance in drug naive patients (to assess primary resistance). These few studies have been conducted in cities or urban areas with referral hospitals and have indeed shown some degree of resistance to ART and have provided some insights into degre...
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