ABSTRACT

The antiinflammatory and antioxidant effects of the ethanolic extract and fractions of Millettia aboensis leaves, a popular Nigerian traditional antiinflammation remedy was investigated. Also, its antimicrobial activity and safety were assessed. The ethanol extract was fractionated into nHexane, chloroform, ethylacetate and methanol fractions.

Phytochemical analysis of the extract and fractions revealed the presence of useful antiinflammatory phytocompounds terpenoids, steroids, flavonoids, tannins, saponins and glycosides.The estimated median lethal dose LD50 of the crude extract was 4699 mg/kg.

The ethanol extract and methanol fraction at 300 and 200 mg/kg showed significant plt;0.05 inhibition of egg albumin induced paw edema. Effects of the extract and methanol fraction on topical edema induced by xylene on mouse ear revealed that methanol fraction at 5 mg had the highest activity with percentage inhibition of 61.90 compared to the 54.76 inhibition produced by Indomethacin at 5 mg. Methanol fraction at 300 mg/kg produced a significant plt;0.05 inhibition of formaldehyde induced arthritis with percentage inhibition of 40.93.

Result of the ulcerogenic effect in rat demonstrated that both the ethanol extract and methanol fraction possess ulcergenic effect though lower than that produced by Indomethacin.

Methanol fraction at 400 mg/kg also produced significant plt;0.05 inhibition of leucocytes migration compared with the control. Both the ethanol extract and methanol fraction produced stabilization effect on the heatinduced and hypotonicity induced red blood cell haemolysis. The antioxidant activity of M. aboensis leave extract and fractions was determined by evaluating its potentials at inhibiting 1,1,diphyenyl2picrylhydrazil DPPH stable radical. Chloroform fraction has the highest antioxidant activity with IC50of 39.81 g/ml. The crude and methanol fraction recorded IC50 of 125.89g/ml each. Ethyl acetate and nhexane fraction has the least activity with IC50 316.23 and 630.96 g/ml respectively.

Antimicrobial studies of the extract and fractions revealed activity against Staphylococcus aureus, Ecoli, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhi, Aspergillus niger and Candida albicans. The ethanol extract has activity against Pseudomonas aeruginosa and Salmonella typhi with MIC of 75 mg/ml for both. The methanol fraction has activity against Staphylococcus aureus, Ecoli with MIC of 37.5, 75 mg/ml respectively and Psudomonas aeruginosa, Aspergillusniger and Candida albicans with MIC of 9.38 mg/ml each. Ethyl acetate fraction showed activity against Staphylococcus aureus, Ecoli, Bacillus subtilis, Salmonella typhi and Candida albicans with MIC of 150, 75, 37.5, 75 and 150 mg/ml respectively. The chloroform fraction produced activity against Aspergillus niger and Candida albicans with MIC of 9.38 and 37.5 mg/ml respectively. Nhexane fraction does not produce any activity against the test organisms. These results suggest that the ethanol leaf extract of M. aboensis possesses antiinflammatory activity that is most active in the methanol fraction while the antioxidant activity is more on the chloroform fraction.

CHAPTER ONE

INTRODUCTION

1.1 Medicinal Plants

Over threequarter of the world population relies mainly on plants and plant extracts for

health care Joy et al., 1998. More than 30 of the entire plant species, at one time or the

other, were used for medicinal purposes Allport, 2000.

Population rise, inadequate supply of drugs, prohibitive cost of treatment, side effects of

several allopathic drugs and development of resistance to currently used drugs for infectious

diseases, have led to increase emphasis on the use of plant materials as a source of medicines

for a wide variety of human ailments. Global estimate indicates that 80 of the world

population still rely upon the use of traditional medicine which are mainly derived from plant

materials Koistinaho and Koistinaho, 2005. In many of the developing countries, the use of

plant drugs is increasing because modern life saving drugs are beyond the reach of threequarter

of the worlds population although many such countries spend 4050 of their total

wealth on drugs Gonzalez and wood, 2001.

Green plants synthesise and preserve a variety of biological products, many of which are

extractable and used as chemical feed stocks or as a raw material for various scientific

investigations. Many secondary metabolites of plants are commercially important and of use

in a number of pharmaceutical companies. However, a sustained supply of the source

material often becomes difficult due to factors like environmental changes, cultural practices,

diverse geographical distribution, labour cost, selection of superior plant stock and over

exploitation by pharmaceutical industries Greenberg et al., 2000. The valuable medicinal

properties contained in certain plants are not, however in doubt.

Plants can provide biologically active molecules and lead structures for the development of

modified derivatives with enhanced activity and/ or reduced toxicity. The small fraction of

flowering plants that have so far been investigated have yielded about 120 therapeutic agents

of known structure from about 90 species of plants Karin and Greten, 2005. Some of the

useful plant drugs include vinblastine, vincristine, taxol, podophyllotoxin, camptothecin,

digotoxigenin, gitoxigenin, digoxigenin, tubocurarine, morphine, codeine, asperin, atropine,

pilocapine, capscicine, allicin, curcumin, artemesinin and ephedrine among others Banerjee

ans Pal, 1994. In some cases, the extract of medicinal plants may be used as medicaments. ...Get Complete Material.