Malaria is a deadly disease caused by a protozoan parasite whose mode of transmission is through a female Anopheles mosquito. It affects persons of all ages; however, pregnant mothers, young children, and the elderly suffer the most due to their dwindled immune state. The currently prescribed antimalarial drugs have been associated with adverse side effects ranging from intolerance to toxicity. Furthermore, the costs associated with conventional approach of managing malaria are arguably high especially for persons living in low-income countries, hence the need for alternative and complementary approaches. Medicinal plants offer a viable alternative because of their few associated side effects, are arguably cheaper, and are easily accessible. Based on the fact that studies involving antimalarial medicinal plants as potential sources of efficacious and cost-effective pharmacotherapies are far between, this research was designed to investigate antiplasmodial and cytotoxic activities of organic and aqueous extracts of selected plants used by Embu traditional medicine practitioners to treat malaria. The studied plants included Erythrina abyssinica (stem bark), Schkuhria pinnata (whole plant), Sterculia africana (stem bark), Terminalia brownii (leaves), Zanthoxylum chalybeum (leaves), Leonotis mollissima (leaves), Carissa edulis (leaves), Tithonia diversifolia (leaves and flowers), and Senna didymobotrya (leaves and pods). In vitro antiplasmodial activity studies of organic and water extracts were carried out against chloroquine-sensitive (D6) and chloroquine-resistance (W2) strains of Plasmodium falciparum. In vivo antiplasmodial studies were done by Peter’s four-day suppression test to test for their in vivo antimalarial activity against P. berghei. Finally, cytotoxic effects and safety of the studied plant extracts were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) rapid calorimetric assay technique. The water and methanolic extracts of T. brownii and S. africana and dichloromethane extracts of E. abyssinica, S. pinnata, and T. diversifolia leaves revealed high in vitro antiplasmodial activities (IC50≤10 μg/ml). Further, moderate in vivo antimalarial activities were observed for water and methanolic extracts of L. mollissima and S. africana and for dichloromethane extracts of E. abyssinica and T. diversifolia leaves. In this study, aqueous extracts of T. brownii and S. africana demonstrated high antiplasmodial activity and high selectivity indices values (SI≥10) and were found to be safe. It was concluded that T. brownii and S. africana aqueous extracts were potent antiplasmodial agents. Further focused studies geared towards isolation of active constituents and determination of in vivo toxicities to ascertain their safety are warranted.

Maerua triphylla root extracts are used by Maasai and Kikuyu communities in Kenya to manage headaches, stomachaches, migraines, and rheumatism. However, scientific data on their safety and efficacy are limited. The current study aims to investigate the safety, phytochemical constituents, analgesic, and anti-inflammatory activities of M. triphylla root extracts. Aqueous and methanol M. triphylla root extracts were prepared by cold maceration, and the extracts’ safety was evaluated using Wistar rats according to the Organization for Economic Cooperation and Development (2008) guidelines. Standard qualitative phytochemical screening methods were used for the detection of various phytochemical groups in the extracts. Analgesic activity assay in Swiss albino mice was done using the acetic acid-induced writhing test, while anti-inflammatory activity was determined in Wistar rats using the acetic acid-induced paw edema method. The methanol and aqueous extracts revealed LD50 > 2000 mg/kg bw, classifying them as nontoxic. The presence of cardiac glycosides, flavonoids, alkaloids, and phenols was observed in both extracts. However, saponins were only present in the methanol extract. In the analgesic study, mice that received 100 mg/kg bw and 500 mg/kg bw of aqueous root extract of M. triphylla had significantly lower acetic acid-induced writhing than mice that received acetylsalicylic acid 75 mg (reference drug) ( p < 0.05 ). Additionally, mice that received 500 mg/kg bw of methanol root extract of M. triphylla had significantly lower acetic acid-induced writhing than mice that received the acetylsalicylic acid 75 mg ( p < 0.05 ). In the anti-inflammatory study, there was no significant difference ( p < 0.05 ) between the inhibitory activity of different doses of the aqueous root extract of M. triphylla and a 50 mg/kg dose of diclofenac sodium (reference drug) on acetic acid-induced paw edema in rats. Moreover, there was no significant difference in the inhibitory activity of 100 mg/kg bw and 500 mg/kg bw doses of the methanol root extract of M. triphylla and a 50 mg/kg dose of diclofenac sodium on acetic acid-induced paw edema ( p > 0.05 ). These findings suggest that the roots of M. triphylla may be useful in the safe mitigation of pain and inflammation and therefore support their ethnomedicinal use in the management of pain and inflammation.

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Background: The use of conventional cancer medication is limited by cytotoxicity on normal cells, intolerability of the drugs used and emergence of aggressive tumors which do not respond to treatment. Herbal alternatives are now being touted to be of promising efficacy. Fagaropsis angolensis (FA) has wide ranging ethno medicinal uses in Kenya. However, the anticancer potential of this plant is yet to be fully explored. The present study aims to determine the antiproliferative activity of crude extracts of Fagaropsis angolensis (FA) against African monkey kidney (Vero, E6), throat cancer (Hep2) and colon cancer (CT 26-CL 25) cell lines. Methods: Water and methanol extracts of FA were qualitatively screened to determine their phytochemical composition. In vitro growth inhibition capacity of these extracts on African monkey kidney (Vero, E6), throat cancer (HeP2) and colon cancer (CT-26-CL-25) cell lines was then assessed using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium assay and expressed as 50% inhibitory concentration (IC 50 ). Doxorubicin (standard anticancer agent) was used for comparison. Results: On Vero cell lines, statistical differences (p<0.05) were noted in the IC 50 values of methanol whole root and methanol root stem extracts of FA (5.80+/-0.80μg/ml) against 1.10+/-0.70μg/ml) as well as between Doxorubicin and methanol root stem extracts of FA (6.5+/-3.25 μg/ml against 1.10+/-0.70μg/ml). On colon cancer cell lines, statistical differences (p<0.05) were noted between the IC 50 values of Doxorubicin and the methanol root stem extract of FA (19.00+/-9.00ug/ml against 8.33+/-1.42μg/ml) as well as between Doxorubicin and methanol whole root extract of FA (19.00+/-9.00μg/ml against 5.25+/-0.35μg/ml). The effects of the extracts of FA on throat cancer cell lines were unremarkable. Conclusions: These findings suggest that the choice of solvent may have some effect on the IC 50 values of the extracts on cancer cell lines. It may also be suggested that the methanol root stem and whole root extracts of FA may be sources of important lead molecules that may be useful in the treatment of colon cancer. Conclusion: These findings suggest that the methanol root stem and whole root extracts of FA may be sources of important lead molecules in cancer therapy. 3,4,5 However, therapy induced toxicity on normal body cells, the emergence of aggressive and therapy resistant tumors, as well as low selectivity indices of some chemotherapeutic agents has limited the efficacy of current conventional therapy. 4,6,7 Therefore, there is a need to search for new sources of bioactive compounds that may serve as starting material in the drug development process. Fagaropsis angolensis is a tree that belongs to the Rutacea family.8 In Kenya, the stem bark is used in ethno medical treatment of malaria while the root is chewed as an expectorant.9,10 The antiproliferative activity of this plant is yet to be reported. The present study was conducted to evaluate the antiproliferative activity of Fagaropsis angolens...

In Kenya, the D. abyssinica rhizome’s decoction is traditionally used to treat urinary tract infections (UTIs), mainly gonorrhea and candidiasis. UTIs are the most severe public health problems that affect over one hundred and fifty million people worldwide annually. They are caused by a wide range of microorganisms where Escherichia coli is known to be the main causative pathogen. Medicinal plants are used in traditional Kenya set up for treatment and most recently as an alternative source of treatment for UTIs due to the increased cost of treatment and many challenges experienced with antibiotic therapy. The current study is designed to investigate the phytochemical composition, acute oral toxicity, and antimicrobial activity of Digitaria abyssinica rhizome extracts against Staphylococcus aureus, Escherichia coli, Neisseria gonorrhea, and Candida albicans. The rhizomes of D. abyssinica were obtained, dried, ground, and extracted using water and organic solvents. The phytochemical assay was carried out using standard phytochemical screening methods. Single-dose toxicity studies were done to determine LD50 while disk diffusion and microbroth dilution techniques were used to determine antimicrobial activity. Results revealed that saponins, phenolics, alkaloids, cardiac glycosides, tannins, flavonoids, steroids, and terpenes were present in the powder, aqueous, methanol, and dichloromethane : methanol extracts. All the extracts had an LD50 of above 2,000 mg/kg of body weight and there was no observation of behavioral changes. Also, the aqueous and methanol extracts revealed antifungal activity against Candida albicans with the lowest average minimum zone of inhibition at MIC of 31.25 mg/ml. The study did not reveal antibacterial activity for any extract against the studied uropathogenic bacteria, Staphylococcus aureus, Escherichia coli, and Neisseria gonorrhoeae. The results from the current study suggested that D. abyssinica rhizome aqueous and methanol extracts have potential antifungal activity against C. albicans, thus validating the folklore of its use to treat candidiasis.