摘要
Objective:To evaluate the anti-inflammatory activity of a tropical African medicinal plant,Costus afer(C.afer)Ker Gawl.in vitro and identify the chemical constituents in the most active fraction.Methods:Hexane,ethyl acetate,n-butanol and aqueous fractions obtained through successive solvent partitioning of 70%methanolic leaf or stem extracts of C.afer were subjected to in vitro anti-inflammatory screening assays viz.anti-denaturation of protein,stabilization of human red blood cell(HRBC)membrane against hypotonicity-induced hemolysis and anti-proteinase activities.Diclofenac sodium was used as a standard drug.The chemical compounds in the most active fraction were determined using quantitative phytochemical and gas chromatography-mass spectrometry(GC/MS)analytical methods,comparing the mass spectra of the GC/MS identified compounds with those of the National Institute of Standards and Technology(NIST)database library.Results:The hexane fraction of C.afer leaf(HFCAL)with an IC50 of 33.36μg/mL,33μg/mL and 212.77μg/mL exhibited the highest anti-denaturation of protein,stabilization of HRBC membrane and anti-proteinase activities respectively when compared with other test fractions.The GC/MS identified compounds in HFCAL known to possess anti-inflammatory property were terpenoids(naphthalene 1,6-dimethyl-;naphthalene 2,3-dimethyl-;phytol),phenol[phenol 2,4-bis(1,1-dimethylethyl)],coumaran[2(4H)-benzofuranone,5,6,7,7a-tetrahydro-4,4,7atrimethyl and fatty acids(pentadecanoic acid;hexadecanoic acid;n-hexadecanoic acid;9,12-octadecanoic acid-methyl ester;9,12,15 octadecatrienoic acid and cis-vaccenic acid)].Conclusion:Therefore,HFCAL could be considered as a potential source of anti-inflammatory agents for herbal formulation or pharmaceutical drug production.
