One form of bioremediation that has been helpful for decades is to introduce either natural or genetically engineered microbes, especially bacteral. For oil spill bioremediation, there are natural and bio engineered bacteria of the class, Pseudomonas.
These bacteria are Oleophilic bacteria or Oil Eating Microbes (OEM). Oil is their major food source, but first, certain conditions have to be met before the microbes can go to work.
In the early stages, certain gaseous or aromatic components of the oil, such as benzene, are toxic to cells. These compounds attack the fatty component of the living cell, disrupting cellular function. When these compounds have vented off, a significant number of life forms can actually thrive on the components of oil! In fact, the life forms that are being discovered in the deepest parts of the ocean are hardy scavengers of whatever vents from the sea floor or drifts down from the surface. Some of these life forms even thrive by converting chemicals into nutrition.
The bottom line is that there are many forms of bacteria, yeasts and fungi as well as higher life forms that can metabolize a wide array of components of the oil for tissue building and for energy production.
The principle behind enhancing and using oil eating bacteria and other life forms is that the major component of oil is hydrocarbon in form and the OEM have especially either evolved or been engineered to thrive on hydrocarbons!
The metabolic process of oil eating by OEM requires an environment where there is the right mix of oxygen, pH of 5.5 to 10, and a temperature between -2° to 60 ° C , or 35.6° to 140° F. Also, over concentration of oil, lack of moisture and lack of oxygen are factors that must be corrected before the hungry little bacteria can start to dine!
In order to help the process of creating a suitable environment for the bacteria, the OEM solution included dispersants that break the oil down to the size of molecule required for digestion and spreads the molecules out, creating more of a surface area for oxygenation. The OEM solution also has its own nutrients that help the bacteria to survive.
When the bacteria do go to work they undergo the following processes: the OEM break down all types of oil hydrocarbons into fatty acids. The fatty acids are then broken down into two types of atoms: carbon and energy. The bacteria then induces a citric acid cycle to finish getting the nutrients and energy, leaving carbon, carbon dioxide and water!
In summary, the first step will have to be to remove the overwhelming excess of oil from the spill site, after which the OEM will have a better environment, where they can thrive and do the work of bioremediation.
Edvotek, “Bioremediation Using Oil-Eating Bacteria”, PDF
