Biochemicalremediation

Soil contamination with oil spills is the major global concern today. Mainly soil contaminated with hydrocarbons has a serious hazard to human health, causes organic pollution of ground water which limits its use, causes economic loss, environmental problems, and decreases the agricultural productivity of the soil (Leung, 2004). Bioremediation uses biological agents, mainly microorganisms i.e. yeast, fungi, bacteria and algae to clean up contaminated soil and water (Strong and Burgess, 2008). This technology relies on promoting the growth of specific micro flora that is native to the contaminated sites thereby able to perform desired activities (Agarwal, 1998). Establishment of such micro flora aids in promoting the growth of new cells through addition of nutrients, by controlling moisture and temperature conditions and adding the terminal electron acceptors. The addition of terminal electron acceptors is our main focus topic because it directly relates to Chemistry.

Microorganisms gain energy by catalyzing energy-producing chemical reactions that involve breaking chemical bonds and transferring electrons away from the contaminant. The type of chemical reaction is called an oxidation-reduction reaction: the organic contaminant is oxidized, losing electrons; while at the same time, the chemical that gains the electrons is reduced. The contaminant is called the electron donor, while the electron recipient is called the electron acceptor. The energy gained from these electron transfers is then used, along with some electrons and carbon from the contaminant, to produce more cells. These two resources, the electron donor and acceptor, are vital for cell growth and are commonly called primary substrates (National Research Council, 1993). Many microorganisms, like humans, use molecular oxygen (O2) as the electron acceptor. The process of destroying organic compounds with the aid of O2 is called aerobic respiration. In aerobic respiration, microbes use O2 to...