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An investigation was carried out to determine the hydrolytic enzymes and the sensitivity
pattern of bacterial isolates from soil samples collected from the tar sand deposit at Gbelejuloda in
Irele Local Government, Ondo State, Nigeria. Bacterial isolates from the tar sand soil were
characterised and identified using standard microbiological technique and their hydrolytic enzymes
and antibiotic sensitivity pattern were determined. Results revealed that all the bacterial isolates
(Proteus mirabilis, Pseudomonas putida, Staphylococcus aureus, Bacillus marcerans, Listeria
monocytogenes, Pseudomonas stulzeri, Listeria grayi and Bacillus polymyxa) screened for
pectinase, protease, amylase and lipase activities possessed at least one of these enzymes. Listeria
monocytogenes had the highest amylolytic activity while Pseudomonas stulzeri had the least. All
the bacterial isolates showed no lipolytic activity except Pseudomonas stulzeri and Listeria grayi.
In addition, Pseudomonas putida had the highest proteolytic activity while Listeria monocytogenes
had the least. Listeria grayi and Bacillus polymyxa produced the highest and the least ability to
degrade pectin. These isolates exhibited different sensitivity pattern to antibiotics such as
streptomycin, gentamycin, tetracycline, ampicillin, colistin and cotrimoxazole. Tar sand constitute
a suitable substratum for bacteria with potential to produce enzymes for industrial purposes.
However, some of these bacterial species are etiological agents of human diseases, therefore
exploration activities of the tar sand should be carried out with adequate provision of medical
facilities for human health protection.
Keywords: Tar sand, bitumen, bacteria, enzymes, antibiotics