ABSTRACT

This study evaluated the isolation and identification of biodegrading fungal species. The sites (Umudike mechanic workshop and Imo lane mechanic workshop) used for this study are designated areas for automobile repairs, petrol/diesel pump sites and generator repairs. Samples collected were cultured on Sabouraud Dextrose Agar using both streak and pour plate techniques. Two (2) fungal species, namely Penicilliurn spp: and Rhizopus spp were isolated and identified based on Morphological and cultural features from engine oil contaminated soil in this study as responsible for the biodegradation of the engine oil. The presence of these fungi in soil samples indicated that the isolates were able to exist in the oil contaminated environment while those that could not survive in this environment being eliminated by the unfavorable conditions caused by the oil. The results from the Zone Diameter Produced on Modified 1% Condemned Oil Agar showed that peniciIlium spp had higher ability to degrade the engine oil as the day of incubation increased. Rhizopus spp also exhibited the ability to utilize the engine oil as its sole source of energy at day 6 but had lesser zone of inhibition compared to Penicillium spp. Therefore, it was seen that the rate of engine oil degradation by Penicillum spp. was faster as the days increased compared to the rate of degradation of engine oil by Rhizopus spp and mixture of Penicillum spp. and Rhizopus' spp. therefore, the study has also shown that fungi play a role in the biodegradation of' oil contaminating soils in the environment. Studies have indicated that biodegradation by fungi could he due to their massive growth and enzyme production responses during their growth phases. Thus in future they can be effectively utilized for the degradation of oil and petroleum products as well as for biodegradation of soil already polluted with oil.