TOTAL MICROBIAL LOAD AND ARYL SULPHATASE ACTIVITY IN HYDROCARBON POLLUTED SOIL REMEDIATED WITH CASSAVA EFFLUENT

ABSTRACT

Petroleum One of the typical environmental pollutants is hydrocarbon contamination. Microorganisms that break down petroleum hydrocarbons are common in nature and can use these substances as sources of carbon and energy. Microorganisms with these traits are frequently used in the bioremediation of areas contaminated by petroleum oil. In this study, 5kg of the soil was dispense in 10 buckets and the soil sample number 6-10 was polluted with 500ml of the contaminated (waste engine oil) which is equivalent to 10% of the weight of the soil samples.  Soil sample 1 acted as general control and soil sample 2-5 acted as treatment control the sample were given treatment (once, monthly, weekly and daily). Total microbial load was carried out with pour plate method and Aryl sulphatase activity was investigated using spectrophotometric method. The highest heterotrophic bacterial count (666.67 x 10⁵ CFU gsoil^-1) was recorded on the polluted soil treated weekly (sample 9) while the least (12x10⁵ CFU gsoil^-1) was from the polluted sample treated monthly (sample 9). The highest fungi count obtained was (5520x10⁴ CFU gsoil^-1) on the polluted sample treated monthly (Sample 8) and the lowest results (80x10⁴CFU gsoil^-1) were obtained from the general control sample (Sample 1). The result obtained showed that there was significant difference in the Heterotrophic bacteria and fungi count based on the different treatment of each of the samples. The enzyme activity profile revealed thatSample 8(polluted and treated monthly) had the highest aryl sulphatase activity with the valueof (0.001142025umol/min). The result showed that the cassava effluent is effective inbioremediation of hydrocarbon soil.