ABSTRACT

A formulated agro-based fluid simply refers to any substance either liquid or gas prepared methodically from agricultural products that cannot sustain, a tangential or shearing force when at rest and that undergoes a continuous change in shape when subjected to stress. This study aims at deteirihining the microbial population in a formulated agro-based fluid. Five microorganisms namely three bacteria and two fungi, capable of utilizing formulated hydraulic fluid as carbon source were isolated from formulated agro-based fluid. The growth profile was determined by monitoring the optical density, total viable count and pH of the highest occurring bacteria culture / in unused samples. The total viable count increased significantly with optical density as the days of incubation progressed to the 6th day. There was a decrease in pH as the days increased. Salmonella species produced the highest optical density and viable count values of 0.802 and 1.32 x i05at the end of the 6th day incubation among all bacteria isolates used in this study. Salmonella species also produced the lowest pH value as well as Escherichia coil with pH values 7.01 and 7.00 respectively after 6 days incubation. Escherichia coli recorded the lowest optical density and viable count values of 0.785 and 1.12 x i05after six days incubation. Staphylococcus aureus had the highest pH. of 7.25 after six days of incubation. No fungi was isolated from unusd samples. The utilization of hydrocarbon in formulated hydraulic fluid resulted in gradual reduction in the oil layer and the disappearance of the oil' with increased incubation. This study has shown that microorganisms are present in formulated agro-based fluid and they have potentials of degrading the formulated agro-based fluid.