Microbial Bioremediation of Hydrocarbons

Environments heavily contaminated with hydrocarbons, such as those affected by oil spills, can be remediated using microbes that metabolize hydrocarbons as a source of carbon and energy.

In such oil spills, while the volatile fractions of hydrocarbons evaporate naturally, the non-volatile fractions persist in the environment and require microbial breakdown.

Alcanivorax borkumensis is a marine bacterium that naturally exists in the environment. Although it is found in low numbers, it quickly multiplies during oil spills.

These bacteria associate with the oil–water interface, forming biofilms and secreting surfactants that emulsify oil into smaller droplets.

This breakdown increases the accessibility of hydrocarbons to monooxygenase enzymes, which incorporate one oxygen atom into alkanes, converting them into alcohols.

The alcohols are oxidized into aldehydes, which are then converted into fatty acids that enter the cell's metabolic pathways.

In some cases, adding nitrogen and phosphorus fertilizers can boost microbial growth and hydrocarbon breakdown, but it must be carefully managed to reduce ecological impacts.