CHAPTER ONE
1.0       INTRODUCTION
Allium satirum  commonly known as garlic is an odoriferous plant belonging to a family lilacease.  It is a small perennial herb with narrow flat leaves and surrounded by membranous patches, it is grown mostly in  Northern Nigeria. It is used primarily for seasoning or spice and also for its medicinal property.  The plant  contain a medicinal properly just like other plants such as aloes, Indian liquorices, alligator pepper etc which are also found useful, although the extend is not accurately recorded.  The medicinal property of garlic is due to its “sulphur” content which was believed to be responsible for it’s medicinal value.  Garlic as a medicinal plant has been widely used and found to be effective on number of serious infections.  Other plants like the ones mentioned earlier also have their medicinal properly, some which is as a result of the presence of ackloids, volatile oils, polyphenol and some related sulphur compound contained in them.  Similarly,  some are found to be used as  vermifuge, stimulating carminative toxic and also as condiments and for treatment of worm bites just like garlic.
The diluted juice of the fresh bulb is used externally as a mild antiseptic and the finely chopped cloves added to food act as an effective vermifuge.  By the distillation of the bulb, a volatile oil consisting mainly of daily disulphide and allyl – prop disulphide is obtained.  It is used to diminish cough in chronic bronchitic.  Meanwhile, in this project work, we shall be working on garlic’s bacteriocidal effect on staphylococcus  aureus. Garlic is one of the best known natural plant that provide sulphur.  Many of the sulphur containing compounds in garlic such as dietlyl – disulphide, propienyl methyl sulphide, allicin which stands as organic disulphide present in garlic inactivates the amino acid.  Cysteine and such reactions of the garlic disulphide present in garlic may inhibit protein synthesis in microorganism.  This reaction may have contributed to the bacteriocidal effect of garlic on bactenal cell.  Garlic also contain a glycoside, vitamin B,C and D and allisation I and II, the volatile sulphur  oil which form part of a vermifugal medicinal property.  An antibiotic substance “allicin” which appear to be more  bacteriostatic than bactericidal has been isolated from the cloves.  Barley (1950).  It has antibiotic effect on both gram positive and gram negative bacteria.  Example Salmonella  typhinurium,staphylococcus  aureus,  Bacillus  Species,  Eshericha   Coli, etc. (Shelef, 1980).
Staphycoccus aureus is a predominant causative agent of skin and urinary tract infection among men and women.  Therefore, urinary tract infection is referred to as infection affecting the urinary system comprising invasion of any of the tissues that make up the tract, extending from the renal cortex to the urethral meatus.  Kunin, (1979).  These  diseases include cystitis – inflammation of bladder, Urethiritis – information of the urethra.  Also, skin infection is referred to as infection affecting the skin.  The organisms are present on the whole skin or part of the skin surface including those in deeper parts of the skin such as the ducts of sebaceous and sweat gland follicles.
Staphylococcus  aureus  is a gram positive bacteria, coagulase-positive and a   human pathogen which live as a commensal in the anterior nares of over half the normal population.  It may also colonize the skin.  It is the most common cause of acute pyogenic (pus-producing)) infection in man. It has a marked predilection for the skin and surface structures and causes boils, carbunches, pustules, styles, impetigo (often in association with streptococcus pyogenes), pemphigus neonatorum, and sticky eyes in babies.  Acute osteomyelitis in children and mastitis in lactating mothers.  It is the commonest cause of infection of wounds and bums.  Other staphylococcal  species are coagulase-negative (Jackson, M.H. CRAWFORD, J.F, MORIS, G. and SMITH P.G. 1989)