Ethnomedicinal use and phytochemical analysis of medicinal plants used to treat gastrointestinal conditions by Awambo people in Iikokola Village, Namibia

Abstract

Namibia is ethnically diverse and rich in indigenous knowledge on the medicinal uses of plants. However, this knowledge in treating gastrointestinal conditions is not well documented despite its contributions to the healthcare system in Namibia. This study aimed at documenting the ethnomedicinal uses of plants used to treat gastrointestinal conditions in the Iikokola village and validating their use through phytochemical analysis. A survey was conducted using semi-structured questionnaires with consenting knowledge holders. Voucher specimens were collected and deposited with the National Herbarium of Namibia for botanical nomenclature. Among the 26 knowledge holders approached 23 participated in the study, of which 16 were females and 7 were males. A total of 19 plant species belonging to 10 plant families were reported to treat at least one gastrointestinal condition and 14 other ailments. Most species belong to Fabaceae and Combretaceae families (FIV=100). The gastrointestinal use of 32% of the plants documented in this study has not been reported elsewhere. Diarrhea, vomiting, and stomach pain are frequently managed using medicinal plants. Decoctions from roots of Grewia tenax, Terminalia sericea, Corchorus tridens, Albizia anthelmintica, and Lantana camara, were mostly used for gastrointestinal ailments. Oral administration was the only route used in the administration of gastrointestinal remedies, among all age groups. Phytochemical compounds such as coumarins, flavonoids, saponins, and tannins which have been linked to the antidiarrheal activity of plants, were detected in organic and aqueous extracts. Organic extracts of T. sericea and G. tenax showed higher total phenolic and flavonoid contents ≤ 169.46 and ≤ 74.03 mg QE/g respectively. These phytochemical properties add value to their ethnomedicinal use is rational although antimicrobial properties and safety profile should be determined. The traditional uses of medicinal plants reported in this study will help safeguard and guide future research aiming at developing plant-based treatments for gastrointestinal conditions.