In Vitro Antiplasmodial Activities and Safety of Ocimum gratissimum L and Rhoicissus tridentate L. F Inorganic and Organic Solvents Extracts

This study evaluated Ocimum gratissimum and Rhoicissus tridentata for their In vitro antimalarial activity and safety. The plant samples collected from Keiyo South in Kenya were processed and their compounds were extracted using inorganic and organic solvents. Phytochemical screening, antiplasmodial bioassays, cytotoxicity tests, and statistical analyses were conducted to validate and compare the efficacies of the two plant used traditionally in treatment of malaria in Kenya. O. gratissimum extracts showed strong inhibition and low toxicity, with methanol as the most effective solvent. Methanol and water solvents extracts demonstrated significant In vitro antiplasmodial activity with inhibition rates of 70.7% and 67.6%, respectively compared to the negative control, whereas R. tridentata extracts, especially those of hexane, had a lower inhibition rate of 36.1%. The Minimum Inhibitory Concentration (MIC) of O. gratissimum extracts was slightly higher than that of the standard antimalarial drug, Artemether-Lumefantrine indicating good antimalarial potency at the slightly higher dose. Cytotoxicity tests revealed that the methanol and water extracts of the two plants extracts were less toxic compared to hexane and dichloromethane solvents extracts. Phytochemical analysis found higher flavonoid content in O. gratissimum and higher carotenoid levels in R. tridentata. Methanol proved to be the most effective solvent, extracting more bioactive compounds than hexane and dichloromethane. The study highlights O. gratissimum as a promising antimalarial candidate and suggests that further optimization is needed to enhance its In vivo efficacy. The findings advocate for continued research into solvent selection, plant part efficacy, and phytochemical analysis to refine and potentially develop these plant extracts into effective therapeutic agents against malaria.