Table 4 presents removal of distillation products. Both bacteria had the ability to degrade refinery products with different boiling range. Degradation of light boiling fractions was between 80-100%. Heavy, high boiling fractions were also degraded by tested isolates. Their removal values reached between 10-80%. The reasons of poor degradability of the high boiling distillates used were their molecular size and physico-chemical parameters (especially water solubility).
Two bacteria strains isolated have special properties for petroleum hydrocarbon remediation, e.g. they produce