In vitro antioxidant capacity and free radical scavenging evaluation of standardized extract of Costus afer leaf

Absolute methanol extract leaf of Costus afer was comprehensively investigated for free radical scavenging activities and antioxidant activities using battery of testing:1,1-diphenyl-2-picrylhydrazyl(DPPH)scavenging,hydroxyl radical scavenging,hydrogen peroxide radical scavenging,2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)(ABTS)scavenging,nitric oxide inhibition,anti-lipid peroxidation,ferrous chelating potential,reducing power potential,total antioxidant capacity,cupric reducing antioxidant capacity CUPRAC and ferric reducing antioxidant power(FRAP).The content of phenol,flavonoid,cupric,anthocyanin were also investigated.The results suggest that the antioxidant potentials of the extract may be responsible for its medicinal potentials.Cell viability assay revealed that up to12g/ml of the extract is safe for Chang liver cell and no sign of toxicity was observed after the extract treatment of 2000 mg/kg in albino rats.

Cytological and biochemical studies during the progression of alloxan-induced diabetes and possible protection of an aqueous leaf extract of Costus afer

Some plants have proven efficacy in the management of diabetes mellitus, of which Costus afer is one. This study was designed to evaluate the cytological and biochemical properties, and comparative ameliorating effects, of an aqueous extract of Costus afer Ker Gawl.(Costaceae) leaf and glibenclamide(GBM), in liver, kidney, and pancreatic injury induced by alloxan. Thirty male albino rats were divided into six weight-matched groups. Group one served as the negative control(non-induced and non-treated, control), while groups 2–6 were alloxan-induced diabetic groups. Group 2 served as a positive control(induced and non-treated, IC), groups 3–5 were treated with different doses of the extract(375, 750, and 1 125 mg/kg body weight) and glibenclamide, respectively. Body weight, absolute and relative organ weights, food and fluid intake, levels of serum glucose and liver enzymes and kidney parameters were calculated and compared. Hepatocytes, renal tubules, and pancreatic cells of diabetic rats, in diabetic non-treated and treated rats were harvested and examined histopathologically. There was dose dependent amelioration on the injuries induced by alloxan on both hepatocytes, renal tubules, and pancreatic cells after treatment with Costus afer. The glucose level was reduced significantly in the Costus afer treated diabetic rats compared with the non-treated diabetic group. Costus afer leaves seem to be effective against diabetic cell injury induced in rat liver, kidney, and pancreas.

Evaluation of Costus afer Ker Gawl.in vitro anti-inflammatory activity and its chemical constituents identified using gas chromatography-mass spectrometry analysis

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.