ABSTRACT
Aims: The aim of the study was to determine the in vivo anti-malarial activity of stem and root extracts of E. abyssinica using the 4-day suppressive in vivo anti-malarial test. Methodology: Female mice weighing approximately 20±2 g were intra-peritoneally injected with mice passaged Plasmodium berghei parasites. The extracts were then administered orally 2 h post-infection and, subsequently, daily for 4 days. On the 4th day, blood smears were prepared from all the mice, stained with giemsa and parasitaemia as well as chemosuppression determined. Results: Comparatively, the root extracts exhibited higher chemosuppression than stem extracts and the level of chemosuppression was dose dependent being the highest at 50 mg/kg and lowest at 12.5 mg/kg. Survival time in extract treated and chloroquine treated groups was 2 to 3 fold higher than the –ve control. Conclusion: These findings suggest that the root extracts are more efficacious in suppressing the development of full blown malaria compared to stem extracts and may be a useful candidate in managing malaria in future.
ABSTRACT
Aims: The purpose of the study was to determine the antioxidant activity, quantify total phenols and total flavonoids and characterize the secondary metabolites present in methanolic extracts of Chamaecrista hildebrandtii and Clerodendrum rotundifolium using liquid chromatography coupled to mass spectrometry (LC-MS). Methodology: The total phenol and flavonoid contents were determined spectrophotometrically while the antioxidant activity was evaluated using the 2, 2-Diphenyl-1-Picrylhydrazyl (DPPH) free radical scavenging method. The secondary metabolites present in the methanolic leaves extracts were evaluated using LC-MS. Results: The extracts of C. hildebrandtii showed a significantly higher antioxidant activity (IC50 = 8.7 mg/mL) compared to C. rotundifolium (IC50= 28.5 mg/mL). Both methanolic extracts of C. hildebrandtii and C. rotundifolium had common and different types of flavonoids such as quercetin, rutin, (+)-catechin 3-O-gallate and luteolin 6-C-glucoside among others that could be responsible for the observed antioxidant activity. The total phenolic content of C. hildebrandtii (1.33±0.07 mg/g tannic acid equivalents) was significantly higher than that of C. rotundifolium (0.25±0.00 mg/g tannic acid equivalents). However, there was no statistically significant difference (p>0.05) in total flavonoid content of C. hildebrandtii (2.69±0.33 mg/g catechin equivalents) and C. rotundifolium (2.36±0.16 mg/g catechin equivalents). Conclusion: The results of the present study suggested that the good antioxidant activity exhibited by C. hildebrandtii may probably have been brought about by various secondary metabolites functioning in synergy.