African Journal of Food Science Vol 3.(12) pp. 406-412, December, 2009 Available online http://www.acadjourn.org/ajfs ISSN 1996-0794 ©2009 Academic Journals Full Length Research paper Microbiological analysis of some vended sachet water in Ogbomoso, Nigeria I. C. Oladipo 1 *, I. C. Onyenike 1 and A. O. Adebiyi 2 1 Science Laboratory Technology Department, Ladoke Akintola University of Technology, P.M.B. 4000, Ogbomoso, Nigeria. 2 Pure and Applied Biology Department, Ladoke Akintola University of Technology, P.M.B. 4000, Ogbomoso, Nigeria. Accepted 16 November, 2009 Water borne bacterial pathogens were isolated from sachet water vended in Ogbomoso, Oyo State, Nigeria. The isolates were characterized and identified as Bacillus subtilis, Bacillus alvei, Pseudomonas putida, Pseudomonas fluorescens, Bacillus cereus, Enterobacter aerogenes and Proteus mirabilis. The antibiotic susceptibility profile of the seven isolates was determined and it was discovered that 59.3% was found sensitive to the commercial antibiotic disc used while 40.7% was resistant. The effect of temperature, pH and sodium chloride concentration on the growth rate of isolates was investigated. It was found that as temperature of incubation increased from 50 to 80°C, the rate of growth of all the isolate decreased and as the pH of the growth medium increased from 3 to 9, the rate of growth of all the isolates also increased. As the concentration of sodium chloride increased from 2 to 5%, the rate of growth of isolates also reduced. Key words: Bacillus subtilis, Bacillus alvei, Pseudomonas putida, Pseudomonas fluorescens, Bacillus cereus, Enterobacter aerogenes and Proteus mirabilis, sachet water, pH, temperature and sodium chloride. INTRODUCTION Water related diseases continue to be one of the major health problems globally. The high prevalence of diarrhea among children and infants can be traced to the use of unsafe water and unhygienic practices (Tortora et al., 2002). Therefore, maintaining a safe drinking water remains essential to human health as transient bacteria contamination may have implication well beyond a period of acute-self limited illness. All living organisms require a wide variety of inorganic compounds for growth, repair, maintenance and reproduction. Water is one of the most important, as well as one of the most abundant of those compounds and it is particularly, vital to living organisms (Tortora et al., 2002). Within the cell, water is the medium for most chemical reactions. It makes up at least 5 - 95% of every cell and the average being between 65 - 75%. In addition, water has been traced to be one of the ways by *Corresponding author. E-mail: xtiecoker@yahoo.com. Tel: +2348032183477. which humans could be infected with various kinds of diseases some water borne diseases include typhoid fever, cholera, bacillary dysentery and so on. In water borne infections, pathogens are usually spread by water contamination with untreated or poorly treated sewage (Tortora et al., 2002). Water is one of the most essential needs for the continued existence of all living organisms on earth. The day-to-day activities of all living organisms required water in whatever form. It is effectively and efficiently put into use by plants, animals, microorganisms and man. In the microbial world, no single microorganism has been discovered to be active at the extreme lack of water for the singular reason that man cannot exist without water, it is of paramount importance to monitor domestic water supply (Sofola and Lawal, 1983). In many developing countries, availability of water has become a critical and urgent problem and it is a matter of great concern to families and communities depending on non-public water supply system (Okonko et al., 2008). Increase in human population exerts an enormous pres-