Endemic medicinal plants of Ethiopia: Ethnomedicinal uses, biological activities and chemical constituents.

ETHNOPHARMACOLOGICAL RELEVANCE: Around 80% of Ethiopians rely on traditional medicinal plants to treat a variety of ailments, and the country is home to a number of endemic plants, making it part of East Africa's hotspot of biodiversity. Despite widespread acceptance of endemic medicinal plants among the local community, comprehensive documentation of their therapeutic uses and phytochemistry is lacking. This review thus provides the first comprehensive appraisal of traditional use, pharmacological properties and phytochemistry of Ethiopian endemic medicinal plants. By storing and preserving indigenous and scientific knowledge about the medicinal benefits of the plants, such documentation generates information database for the future. It also aids the conservation of key medicinal plants along with translational research to accelerate the development of pharmaceuticals. AIM OF THE REVIEW: The aims of this review are to collect and document current information on the ethnopharmacological uses, phytochemistry, and biological activities of Ethiopian endemic medicinal plants, identify research gaps, and provide perspectives and suggestions for future research on the plants as potential sources of pharmaceuticals. MATERIALS & METHODS: A comprehensive literature review using electronic databases such as Medline, Web of Science, Google Scholar, ScienceDirect, SpringerLink, and Wiley Online Library was conducted for collecting relevant information. The World Flora Online (WFO) database and the International Plant Names Index (IPNI) were utilized to authenticate the taxonomic information of the plants. Chemical structures were drawn using ChemBioDraw Ultra 12.1 and verified via PubChem. RESULTS: The present review has identified 412 Ethiopian endemic plants. Out of the 412 endemic plants species recorded for Ethiopia 44 are medicinally valuable to mitigate a myriad of diseases, and nine (27.3%) of them are endangered. Our literature survey also found out that a total of 74 compounds were isolated and characterized from the endemic plants, with phenolics accounting for the majority of them (66.2%). The plants exhibited antimalarial, antimicrobial, anticancer, anthelmintic, mosquitocidal, antidiabetic, antioxidant, and anti-inflammatory properties. CONCLUSION: The work has resulted in an up-to-date inventory of Ethiopia's endemic flora, as well as the identification of species with traditional medicinal uses. The pharmacological activity and phytochemistry of numerous endemic plants with various traditional therapeutic claims are yet to be researched scientifically. Scientific validation of the herbal remedies, including evidence-based safety and efficacy studies are, therefore, crucial. The endangered medicinal plants must be conserved in order for local communities to have access to them in the future.

In vitro Antileishmanial Activity of Some Ethiopian Medicinal Plants.

INTRODUCTION: Leishmaniasis is a group of diseases caused by protozoan parasites, which remains a burden for developing countries. The lack of a vaccine as well as the emergence of resistance toward the recommended drugs pose a challenge for the control of the disease. This urges the demand for new antileishmanial agents to prevent and treat this disease. Consequently, four Ethiopian plants were selected and tested for their antileishmanial activity against two Leishmanial parasites. METHODS: Methanol (80%) was used to macerate the plant materials. In vitro antipromastigote activity of the crude extracts was then tested against promastigotes and axenically cultured amastigotes of Leishmania aethiopica and Leishmania donovani clinical isolates using Alamar Blue assay, and cell viability was measured fluorometrically. 1% DMSO and the media were used as a negative control while amphotericin B was used as a positive control. Furthermore, preliminary phytochemical analysis of the extracts was performed. RESULTS: From the four plants' extracts, Ferula communis and Otostegia integrifolia showed better activity with IC50 value of 11.38±0.55 and 13.03±0.87 µg/mL against L. aethiopica, respectively. However, the same plant extracts exhibited lower activity against L. donovani with IC50 values of 23.41±2.32 and 17.24±1.29 µg/mL, respectively. O. integrifolia exhibited highest effect against amastigotes of L. aethiopica (IC50: 16.84±0.65) and L. donovani (IC50:14.55±0.38). F. communis resulted second highest in growth inhibition against amastigotes of L. aethiopica and L. donovani with IC50 value of 14.32±0.54 and 31.12±0.19, respectively. The phytochemical analysis of the extracts indicated the presence of phenol, flavonoids, tannins, saponins, terpenoids, and alkaloids. CONCLUSION: The findings from this study demonstrate that crude extracts of F. communis and O. integrifolia showed promising antileishmanial activity against L. aethiopica and L. donovani that may be attributed to the presence of different secondary metabolites.

Evaluation of Analgesic and Anti-inflammatory Potential of 80% Methanol Leaf Extract of Otostegia integrifolia Benth (Lamiaceae).

INTRODUCTION: Pain and inflammatory disorders are the most prevalent syndromes. Different herbs were used for treatment of pain and inflammation including members of the genus Otostegia. As a result, this research investigated the in vivo analgesic and anti-inflammatory effects of 80% methanol leaf extract of Otostegia integrifolia in mice. METHODS: The analgesic and anti-inflammatory effects of the plant was evaluated using hot plate method, acetic-acid induced writhing test, and carrageenan and formalin induced paw edema. Three experimental groups (100, 200, and 400 mg/kg) received the extract while morphine 10 mg/kg and aspirin 150 mg/kg were used as a positive control for analgesic and anti-inflammatory tests accordingly. Distilled water (10 mL/kg) was used as negative control. RESULTS: From the experimental groups, OI400 displayed significant analgesic and anti-inflammatory activities (P<0.001). In acetic acid induced writhing tests, the number of writhes decreased significantly (P<0.001) in all experimental groups. Similarly, OI400 reduced the mean paw edema significantly in carrageenan and formalin induced paw edema (P<0.05 and P<0.001, respectively). CONCLUSION: In general, the results obtained in this study demonstrated that the extract exhibited significant analgesic and anti-inflammatory potential in mice.