The use of herbs and medicinal plants as the first medicines is a universal phenomenon. Every culture on earth, through written or oral tradition, has relied on the vast variety of natural chemistry found in healing plants for their therapeutic properties(1). All drugs of the past were substances with a particular therapeutic action extracted from plants. Thus, medicinal plants may be defined as any plant that can be put to culinary or medicinal use such as fox glove, opium poppy, and garlic (2) . More and more researchers find that food and their individual constituents perform similar fashion to modern drugs and sometimes better without the dreaded side effects(1) The onion is one of the oldest cultivated vegetables in history. It is thought that bulbs from the onion family have been utilized as a food source for Millennia. Onion consists of its herbaceous plant part and its edible bulb part. It is probably a native to southwestern Asia (3). The leaves are bluish –green and hollow. The bulbs are large, fleshy and firm. There are three main varities- white, red and purple skinned (4).The relative pungency of onion has both genetic and environmental components. Sulphur compounds in onions have also been shown to be anti-inflammatory both by inhibiting formation of thromboxanes and by inhibiting the action of platelet-activating factor (PAF). Thiosulfinates condition anti-thrombotic benefits, including antioxidant activity(5,6) reduced serum cholesterol and enhance in vitro platelet activity (7). This later effect is important for cardiovascular health by reducing the probability that platelets aggregate in the blood, a major cause of he!

art attacks and strokes (8). Hence, thiosulphinates found in onion have been shown to inhibit in-vitro platelet aggregation(9, 10). Flavonoids are a second class of health enhancing compound produced by onions, an example is quercetin. Flavonoids are chemical compounds active against microorganisms. They have been found in-vitro to be effective antimicrobial substance against a wide array of microorganisms (11). Ginger, consists of the fresh or dried roots of Zingiber officinale. In humans, ginger is thought to act directly on the gastrointestinal system to reduce nausea (12). Traditionally, ginger has been used to treat intestinal infections, especially related with digestive problems. Equally, its antibacterial ‘power' is effective against preventing numerous intestinal problems that take place as a result of the alteration of the intestinal flora. This is ideal to avoid the formation of ulcers by eliminating the Helicobacter pylori, a bacterium whose secretions of ammoni!

a are responsible for many ulcers, especially those of the duodene, an d for other stomach problems like gastritis, since the plant is able to neutralize the excess of gastric acid that is another of the causes that favours the formation of ulcers (5). The gingerols have analgesic, sedative, antipyretic, antibacterial and gastrointestinal tract motility effects. Ginger has the capacity to eliminate harmful bacteria, such as Escherichia coli, responsible for most of the diarrhoea, especially in children(13). Ginger eases both diarrhoea and constipation; hence it should have impact on the growth of Bacillus cereus, which mainly causes diarrhoea and nausea. It has been shown to reduce the stickiness of blood platelets, hence may help reduce risk of artherosclerosis(13, 14) The genus Salmonella is among the most common causes of food and water borne infectious diseases in the world (15). The organism has a wide host range which comprises most animal species including mammals, birds and cold-blooded animals in addition to human. A number of studies in Nigeria have shown that Salmonella infections is endemic in many parts of the country (16. 17) and its endemicity increases especially in areas with low environmental hygien (18-21).

Bacillus subtilis has been implicated in various food spoilage including ropiness in bread, production of CO2 in canned meats, sliminess and coagulation in milk, e.t.c(22). Escherichia coli is one of the main causes of both nosocomial and community-acquired infections in humans and one of the micro-organisms most frequently isolated from blood. E. coli in humans is a common inhabitant of the gastrointestinal tract. It can also cause various intestinal and extra-intestinal diseases (23). The pathogenic isolates of E. coli have a relatively large potential for developing resistance (24, 25). The spread of microbial drug resistance is a global public health challenge, which impairs the efficacy of antimicrobial agents and results in substantial increased illnesses and death rate, hence, this work was therefore undertaken to investigate as well as authenticate the antimicrobial potentials of the two medicinal plants (26, 27).The antimicrobial properties of plants have been inves!

tigated by a number of researchers world wide, especially in Latin America. In Argentina, a research tested 122 known plant species used for therapeutic treatments (28). It was documentedthat among the compounds extracted from these plants, twelve inhibited the growth of Staphylococus aureus, ten inhibited Escherichia coli, and four inhibited Aspergillus niger and also reported that the most potent compound was one extracted fromTabebuia impetiginosa. The antimicrobial properties of compounds obtained from Parthenum argentatum against Candida albicans, Torulopsis, Hansemula, Klebsiellapneumoniae and Pseudomonas aeruginosa was detected (29,30).Work done was observed that the substances extracted from nine known plants in Uruguai did not show any activity against C. albicans and Saccharomyces cerevisiae, but inhibitedthe growth of Bacillus subtilis, E. coli and P. aeruginosa (31). Many studies have been conducted in Brazil. The inhibitory activity of Vatairea macrocarpa on Kl!

ebsiella spp. and S. aureus was observed (32) and the inhibitory activ ity of extracts from Eucaliptus spp. against soil fungi (33). A more detailed study on antimicrobial compounds was done evaluating extracts from 120 plant species from 28 different families (34). It was documented that 81 extracts obtanained from 58 plants were active against S. aureus, and five extracts from four other plants inhibited the growth of P. aeruginosa. Another study (35) detected the antibacterial and antifungal (C. albicans) activityof essential oils obtained from Croton triangularis leaves. Extracts from Lippia gracilis and Xylopia sericea showed antifungal activity. The investigation of antimicrobial activity as well as cell toxicity of extracts from 30 plant species againstfive bacteria species and two fungi species was studied (36). It was concluded that ethanol extracts from 70 % of the plants were toxic to cell and only one of the species of Combretum duarteanum showed antimicrobial activity. The toxicity of extracts from Arthemus sativa, which is known t!

o have antimicrobial activity, was also studied (37). The antimicrobial activity from Mikania triangularis, known as “thin leaf guaco”, was tested against five genera of bacteria and three genera of yeast, and showed it had activity against Bacillus cereus, E. coli, P. aeruginosa, S. aureus and S. epidermidis (38). Effects of phytochemical were conducted (39,40) and it was observed the antimicrobial activity of anacardic acid on S. aureus, Brevibacterium ammoniagenes, Streptococcus mutans and Propionibacterium acnes. Later, it was tested the bactericidal activity of anacardic acid and totarol on methicillinresistant strains of S. aureus (MRSA) and the synergistic effect of these compounds associated with methicillin (41). Plant extracts have great potential as antimicrobial compounds against microorganisms (42) and this study reported that they can be used in the treatment of infectious diseases caused by resistant microbes. In addtion, this study suggested that the syner!

gistic effect from the association of antibiotic with plant extracts a gainst resistant bacteria leads to new choices for the treatment of infectious diseases. This effect enables the use of the respective antibiotic when it is no longer effective by itself during therapeutic treatment.

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