Abstract
Global industry depends on fossil fuels as a primary energy source. Due to fossil fuel imports/exports and manufacturing, there is a high risk of environmental pollution, and consequently severe ecological disruption, as a result of fuel by-products and spills in areas where storage, transport, refining, distribution, consumption and fossil fuel-related industries exist.
Hydrocarbons have traditionally been considered to be of biological origin, since methane and other longer chain hydrocarbons appear to be exclusively the result of biological processes. However, it is now known that the largest supply of carbon in the planetary system is in the form of hydrocarbons. Petroleum and coal contain a class of molecules known as hopanoids commonly found in bacterial cell walls (Gold 1985): thus, it can be concluded that at some point all of these fuels originated, at least in part, from microbes. Based on this, the assumption can be made that biodegradation of these fuels has always been occurring to some extent. To extrapolate from this knowledge, the biological origins of these hydrocarbons could be the reason that the adaptation of microbes to degrade them so readily occurs upon technological industrialisation of the Earth, and why phytoremediation is such an applicable method for polluted soil reclamation. Microorganisms, natural or genetically engineered, can mineralise toxic polycyclic aromatic hydrocarbons (PAHs) into carbon dioxide and water (Fig. 6.1).
