A survey of plant remedies for livestock diseases in the Mnisi community, South Africa, and investigation of their biological activities

Ethnoveterinary medicine (EVM), although not well documented, serves as an alternative or complementary medication for infectious diseases and parasites in South African livestock. In this study, plant species and traditional remedy formulation methods used by the Mnisi community, Bushbuckridge, in EVM were documented using Rapid Rural Appraisal techniques. Three plant species were selected for evaluation of antimicrobial, antibiofilm and cytotoxic activities based on their frequency index and lack of published information on their bioactivity. Traditional methods were used for plant extraction using water. Acetone was used as an organic solvent to compare traditional and organic solvent methods of extract preparation. The extracts were tested for their antimicrobial activity and cytotoxicity. Elephantorrhiza obliqua acetone extract had the best antibacterial activity with a minimum inhibitory concentration (MIC) value of 0.09 mg/ml against Pseudomonas aeruginosa, while E. obliqua water extract had the best antifungal activity with MIC of 0.02 mg/ml against Aspergillus fumigatus. Some extracts also inhibited biofilm formation by at least 50% and were active against mature biofilms. Only two of the nine plant extracts were relatively toxic against Vero cells. Interestingly, traditionally prepared remedies were generally more active against fungi and mycobacteria and less cytotoxic than organic solvent extracts. In vivo studies are necessary to support the traditional use and safety of the remedies against livestock diseases.