biodegradation and bioremediation

1. Biodegradation and Bioremediation Dr Sujit Ghosh

2. Bioremediation & Biodegradation

4. Bioremediation – using biological systems to treat contaminated sites Biodegradation – biological activity that results in the break down of a specific contaminant Bioaugmentation – adding biodegrading organisms to the contaminated site (not genetically manipulated) Biostimulation – adding nutrients like nitrogen or phosphorus in order to stimulate microbial activity

9. Growth support No growth support Aerobic Anaerobic

12. BIOREMEDIATION Bioremediation is a process of waste management in which microorganisms are used to remove or neutralize pollutants from a contaminated site. bioremediation is a “treatment that uses naturally occurring organisms to break down hazardous substances into less toxic or non toxic substances”. bioremediation - the branch of biotechnology that uses biological process to overcome environmental problems. bioremediation - the act of treating waste or pollutants by the use of microorganisms (as bacteria) that can break down the undesirable substances.

13. Bioremediation technologies Technologies can be generally classified as in situ or ex situ. In situ bioremediation involves treating the contaminated material at the site, while ex situ involves the removal of the contaminated material to be treated elsewhere. Genetic engineering approaches Genetic engineering to create organisms specifically designed for bioremediation is an effective method. The very radio-resistant organism, Deinococcus radiodurans has been modified to consume and digest toluene and ionic mercury from highly radioactive nuclear waste. Mycoremediation This is a form of bioremediation in which fungal organisms are used to decontaminate the area. The term involves specifically the use of fungal mycelia in bioremediation. The mycelium secretes extracellular enzymes and acids that break down lignin and cellulose which are organic compounds consisting of long chains of carbon and hydrogen. Wood-degrading fungi are particularly effective in breaking down aromatic pollutants (toxic components of petroleum), as well as chlorinated compounds (certain persistent pesticide).

14. Bioremediation is also called Biodegradation Enhancement and includes any purposful use of microbes to degrade unwanted substances in the environment

17. In situ and ex situ methods • Land farming: • Solid-phase treatment system for contaminated soils: may be done in situ or ex situ.Composting: • Aerobic, thermophilic treatment process in which contaminated material is mixed with a bulking agent; can be done using static piles or aerated piles. • Bioreactors: • Biodegradation in a container or reactor; may be used to treat liquids or slurries. • Bioventing: • Method of treating contaminated soils bydrawing oxygen through the soil to stimulate microbial activity. • Biofilters: • Use of microbial stripping columns to treat air emissions. • Bioaugmentation: • Addition of bacterial cultures to a contaminated medium; frequently used in both in situ and ex situ systems. • Biostimulation: • Stimulation of indigenous microbial populations in soils or ground water by providingnecessary nutrients. • Intrinsic bioremediation: • Unassisted bioremediation of contaminant; only regular monitoring is done. • Pump and treat: • Pumping ground water to the surface, treating, and reinjecting