Ethnomedicinal uses and nutritional composition of yams (Dioscorea hispida Dennst.) In Kitholhu, Kasese District, Uganda

Abstract

Yams (Dioscorea species) are traditionally valued as famine foods and medicinal lianas in countries such as Uganda, Indonesia, Ethiopia, Sudan, Thailand and Singapore. However, little information exists on the traditional medicinal uses and nutritional composition of yams in Uganda, despite them being cultivated and considered to have medicinal benefits in Eastern and Western Uganda. This study was sought to document the ethnobotanical knowledge and assess the nutritional composition of Dioscorea hispida Dennst. (D. hispida) in Kasese District of Western Uganda. An ethnobotanical survey was carried out from November 2022 to May 2023 in Kitholhu subcounty, a flood-prone area in Kasese District to assess the indigenous knowledge on the medicinal uses of D. hispida. Using semi-structured questionnaires, a total of 47 respondents selected using snow ball technique were interviewed. The proximate composition (moisture, ash, crude fat, protein, crude fiber and total carbohydrate contents) of sampled D. hispida tubers were analyzed. The ethnobotanical data obtained was analyzed using descriptive statistics while nutritional data was subjected to a one-way analysis of variance at P < 0.05. Up to 83% of the respondents cultivate D. hispida, with 94% of these indicating that the tuber is used in traditional management of typhoid, diabetes mellitus, malaria, yellow fever, intestinal inflammation, cancer, peptic ulcers and hypertension, among other ailments. Proximate analysis indicated that D. hispida samples from Kitholhu had 72.29 ± 0.38% moisture, 6.08 ± 0.15% crude fiber, 1.24 ± 0.05% crude fat, 3.05 ± 0.03% ash, 5.65 ± 0.29% proteins and 11.67 ± 0.52% carbohydrates. Our results suggest that there is rich ethnobotanical knowledge on the use of D. hispida for the treatment of ailments among the local communities of Kitholhu. Thus, D. hispida is a famine and medicinal plant that needs to be considered for conservation to enhance food security in Kitholhu and Uganda as a whole. Further studies are required to assess D. hispida for its claimed bioactivities against the reported diseases and conditions.