No abstract

Aims: The present study was conducted to determine the antioxidant activity and chemical components of Ficus abutilifolia. Miq. (Moraceae). Place and Duration of the Study: The study were performed at Department of chemistry, University of Ngaoundere, Cameroon, between July 2017 and September 2018. Methodology: Phytochemical study was carried out on all extracts of stem barks. Besides, the total phenols contents (TPC) using the Folin-Ciocalteu and the antioxidant activities using DPPH and FRAP methods were also evaluated. The isolation of compounds from the EtOAc extract was done using column and thin layer chromatographic techniques on silica gel. The structures of isolated constituents were elucidated using mass spectrometry, 1D and 2D-NMR techniques. Results: Phytochemical screening revealed that all the compounds tested were found to be present in the acetone extract; the hexane extract was the poorest in compounds. Acetone extract, DCM/MeOH (1:1) and MeOH extracts were found to be rich in phenols with TPC respectively (239. 849 ± 0.969), (232.676 ± 0.404) and (109.654 ± 0.724) mg EAG/100g EX. Except the n-hexane extract, all the others exhibit antioxidant activities, acetone extract being the most effective with an inhibitory concentration 50 (IC50) of (0.038 ± 0.002) mg/mL for the DPPH antiradical scavenging activity and (0,021 ± 0,002) mg/mL for FRAP. A new fatty acid named Pentacosyl henicosanoate (2) along with six known compounds Octatriacontane (1), β–sitosterol (3), a mixture of Lupeol acetate (4a), α-amyrin acetate (4b), β-amyrin acetate (4c) and Daucosterol (5) were isolated from the column chromatography of the ethyl acetate extract. Daucosterol (5) exhibited antiradical activity with an IC50 of (13.005 ± 0.005) mg/mL. Only Daucosterol (5) has exhibited antiradical activity with an IC50 of (13.005 ± 0.005) mg/mL among the isolated compounds. Conclusion: This study provides scientific evidence and support for the traditional uses of F. abutilifolia stem barks in the treatment of diseases associated with oxidative stress.

The present study reports the chemical constituents, antioxidant, anticonvulsant and α-amylase activities of the aerial part of Cyperus rotundus collected in Cameroon. Phytochemical study leads to the isolation of six known compounds alongwith lupeol (1), stigmasterol (2), tetracosanoic acid (3), a mixture of β-sitosterol (4a) and stigmasterol (4b), ursolic acid (5) and saikogenin F (6). Compounds 3, 5 and 6 were isolated for the first time from this species. The structures of these compounds were determined using spectroscopic analysis including 1D and 2D NMR, mass spectrometry and comparison with the literature data. Biological activities carried out on the extracts showed that the methanol extract exhibited good antiradical scavenging activity against DPPH radical (IC50 = 2.873 μg/mL) and very good ferric reducing antioxidant power (FRAP) (IC50 = 7.535 μg/mL). It appeared that the mixture of hexane and ethyl acetate extract at the dose 100 mg/kg protected 66% of mice against convulsion induced by the pentylenetetrazol and 50% of protection when using picrotoxin at the same dose. All the extracts and compounds from this plant showed no inhibition against α-amylase related to antidiabetic activity.