Evaluation of bioactive compounds and antioxidant activities of dichloromethane leaf extracts of Ficus trichocarpa and Lasianthera Africana

Abstract

This study evaluated the bioactive compounds present in the dichloromethane leaf extracts of Ficus trichocarpa and Lasianthera africana and also assessed the antioxidant activities of the same leaf extracts. The plant materials were washed under running water to remove foreign matters, air-dried at ambient temperatures under a shade for up to 2 weeks, and afterwards pulverized into coarse powders. The bioactive compounds were analysed using Gas Chromatography-Mass Spectrometry (GC-MS) while the antioxidant activities were assessed by ferric reducing antioxidant power (FRAP) assay, DPPH radical scavenging assay, and hydroxyl radical assay. The results of phytochemical content showed that the leaves are rich in secondary metabolites such as alkaloids, terpenes, flavonoids and non-flavonoid phenolics. Quantitatively, alkaloids were the most abundant secondary metabolites (55.73%) present in the leaf of F. trichocarpa. On the other hand, terpenes were the most abundant secondary metabolites present in the leaf of L. Africana (55.45%). The results of antioxidant assay revealed that both F. trichocarpa and L. africana leaves exhibited high antioxidant activities in a dose-dependent manner: 69.52% and 52.08% respectively at 100 μg/ml for DPPH scavenging activities; 73.18% and 65.65 % respectively at 200 μg/ml for FRAP assay; and (86.25% and 67.08 % respectively at 200μg/ml for hydroxyl radical activities. In conclusion, the dichloromethane leaf extracts of F. trichocarpa and L. africana are rich in secondary metabolites such as alkaloids, terpenes, flavonoids and non-flavonoid phenolics. The leaf extracts also have high antioxidant property.