Maerua angolensis DC: evaluation of the oral acute and sub-chronic toxicity profile of its freeze-dried leaves infusion extract

Maerua angolensis is a shrub/small tree that grows up to about 10 m tall. The plant is widely distributed in tropical Africa and used in various ethnomedicinal applications across the region. The objective of this study is to investigate the oral safety profile of the infusion extract of Maerua angolensis (IEMa) in laboratory animals. Hippocratic screening was adopted to evaluate the acute toxicity profile using 2000 mg/kg of IEMa, p.o. in mice. The sub-chronic toxicity was performed by daily oral administration of IEMa (800 mg/kg) in Wistar rats for 28 days and clinical observations and toxicological related parameters were recorded. After the treatment period, blood was collected for hematological and biochemical analysis, and organs were removed for macroscopic analysis. The agent exhibited mild symptoms and no mortality recorded in the Hippocratic screening. In the sub-chronic test, few changes in urine output, platelets counts and alkaline phosphatase were observed, but are within the physiological ranges for this animal specie. The results shows that IEMa does not present oral toxicity thereby displaying a wide safety margin for therapeutic use.