| dc.description.abstract | Emergence of non-communicable diseases has posed a great health challenge worldwide. Particularly; prevalence of diabetes mellitus has been on the increase among communities of both developed and developing countries. In Kenya, studies carried out in 2011 rated diabetes prevalence at 29.4 % in central Kenya and as low as 2.4% in Rift Valley; an area largely inhabited by pastoral communities such as the Maasai of Narok County. Nyeri County leads in diabetes prevalence in Kenya at 12.6%. This study aimed at investigating ethnobotanical knowledge of traditional herbal practitioners (THPs) from two socio-culturally diverse communities that live in Narok and Nyeri Counties. It also sought to understand traditional antidiabetic plants that they used to treat and manage diabetes in their communities.Thirty traditional herbal practitioners were purposively selected from each County to participate in a cross-sectional survey. They were drawn from each of the six constituencies of Nyeri County (namely; Mukurwe-ini, Kieni, Tetu, Othaya, Mathira and Nyeri town) and Narok County (namely; Emurua Dikirr, Narok East, Narok South, Narok North, Narok West and Kilgoris). A specimen of each plant that was mentioned was collected, given a voucher number, and deposited at the herbarium, in the School of Biological Sciences. From the survey findings, two antidiabetic plants were selected, they included aqueous root extracts of Dovyallis abyssinica and leaves of Sonchus luxurians. They were investigated for phytochemical constituents, antidiabetic activity and acute toxicity. Doses of 25, 75 and 225mg/kg body weight were used in antidiabetic investigations. Acute toxicity was carried out based on ―Organization for Economic Co-operation and Development‖ 2001 guidelines.
The survey findings in Nyeri County documented a total of 80 diseases. They included respiratory diseases (53.3%), malaria (50%) and gonorrhea (40%). Non-communicable diseases included; hypertension (43%) and arthritis or gout (40%). A total of 111 medicinal plant species distributed within 98 genera and 56 families and their ethnobotanical uses were documented. Plant families showing high representation of medicinal plants was Asteraceae (9.5%). Rotheca myricoides, Prunus africana, Kigelia africana, Croton megalocarpus, Warbugia ugandensis and Cordia abyssinica were most cited. Seventeen (17) plant species were documented as antidiabetic medicinal plants for the first time. They included; Sonchus luxurians, Clematis hirsute and Periploca linearifolia.
In Narok County, communicable diseases that were treated by Traditional Herbal Practitioners included; stomach ache (11.7%), malaria (10%), respiratory diseases (9 %) and syphilis (6.9 %). Non communicable diseases included, heart burn (5.8%), cancer (4.8%) and fibroids (4.2%). Plant family Mimosaceae had the highest number of plants cited. Plants with high user value included Aloe Secundiflora, Warburgia salutaris, Toddalia asiatica, Rhamnus prinoides and Zanthozylum usambarense. Nine antidiabetic plants were documented for the first time, for instance Dovyalis abyssinica and Faurea saligna. Phytochemicals present in both Dovyallis abyssinica and Sonchus luxurians included; alkaloids, tannins, saponins, phenols, phytosterols and glycosides. At a dose of 75 and 225mg/kg body weight, both plant extracts demonstrated antihyperglycemic activity at P<0.05 significant level, both in post prandial test and in diabetic mice. The extracts showed mild toxic effects at 2000mg/kg body weight.
The study concluded that, Traditional Herbal Practitioners from Nyeri and Narok County were richly endowed with traditional medicinal knowledge, however, majority were aged. There was lack of clientele and apprenticeship in Nyeri County. Aqueous extracts of the selected antidiabetic plants; roots of Dovyallis abyssinica and leaves of Sonchus luxurians were safe, possessed antidiabetic activity and antidiabetic phytochemicals. The findings validated their ethnotherapeutic use in the management of diabetes. The study recommended further survey on the use of medicinal plants among community members from Narok and Nyeri County to reinforce findings from Traditional Herbal Practitioners. It also recommended sub-acute and chronic toxicity studies of the two plants to further ascertain their safety. | en_US |
