Transcript Chapter 9: Bioremediation - Kennesaw State University College of
Bioremediation
The use of biological agents, such as bacteria or plants, to remove or neutralize contaminants, as in polluted soil or water.
Any processes that uses microorganisms or their enzymes to natural environment altered by contaminants to its original condition.
Each year, industrial residues, domestic waste and agricultural run-offs contaminate water, soil and air. The U.S. spends millions of dollars to clean contaminants, prevent further pollution, and restore the site to its natural vegetative state.
Bioremediation is used to clean up environmental hazards cause by industrial toxic waste.
The contaminants are metabolized and transformed into harmless organic and inorganic molecules: › nitrogen, carbon dioxide and salts.
In-Situ & Ex-Situ
In-situ
bioremediation- clean up of chemicals at the contaminated site
Ex-situ
bioremediation- removal of chemicals from the contaminated site to another location for treatment
The
Exxon Valdez oil spill
occurred in Prince William Sound, Alaska, on March 24, 1989.
The
Exxon Valdez
, an oil tanker bound for Long Beach, California, struck Prince William Sound's Bligh Reef and spilled 260,000 to 750,000 barrels (41,000 to 119,000 m 3 ) of crude oil.
It is considered to be one of the most devastating human caused environmental disasters .
› The Environmental Protection Agency (EPA), used
Pseudomonas
developed by Ananda Chakrabarty to degrade components in crude oil.
Exxon Valdez oil Spill
The
Deepwater Horizon
oil spill ( BP oil spill, the Gulf of Mexico oil spill, the BP oil disaster or the Macondo blowout), an oil spill in the Gulf of Mexico which flowed for three months in 2010.
It is the largest accidental marine oil spill in the history of the petroleum industry.
Scientist believes that that natural bacteria will slowly degrade the toxic waste.
When the influx of oil from the Deepwater Horizon leak began, it is likely bacteria began consuming and reproducing rapidly, breaking down oil into byproducts such as carbon dioxide, water and other biomass.
• • • • Crude Oil Spill, Bemidji, Minnesota Exxon Oil spill, 1989 Pesticides, San Francisco, Bay Estuary Oil release by Kuwait, 1991
Ex-Situ
bioremediation requires that the contaminated soil or water be physically removed before treatment.
• • • • Removal of contaminants at different location taken from the contaminated site More expensive and damaging to the area More difficult compare to In-situ bioremediation Examples:
Sewage Treatment
A new and growing type of bioremediation is phytoremediation.
Phytoremediation is the depolluting of contaminated soil, water or air using plants.
• • It is use of plants to clean up potentially damaging spills. The plants work with soil organisms to transform contaminants, such as heavy metals and toxic organic compounds, into harmless or valuable forms.
Examples: Cottonwood, poplar trees and Alpine pennycress have been used extensively to leach heavy metals.
Used by: › United States Department of Agriculture (USDA) › Department of Energy (DoE) › EPA Alpine pennycress is used by the USDA to remove heavy metals such as zinc and cadmium.
Phytoremediation’s most publicize appearance came during the Chernobyl nuclear waste cleanup in the Ukraine.
Sunflower plants were planted to remove and degrade radioactive cesium and strontium.
http://www.google.com/hostednews/ap/article/ALeqM5jIj 3ZyLIOY pLjO7m6Z_Llr7x1nQ?docId=29c8cbbf334a420a9584c45 a2f05298c
Arabidopsis thaliana
, a plant in the mustard family, has two bacterial genes added to its genome in order for the plant to remove arsenic from the soil. The first gene converts the arsenic to a form the plant can suck up and the second allows the plant to detoxify heavy metals and accumulate them in its leaves .
Polaromonas naphthalenivorans
, breaks down naphthalene in coal tar. Found in Upstate New York and identified by the use of DNA finger printing.
Geobacter sulfurreducens
, part of a family of bacterium that degrade metals.
G. sulfurreducens
degrades uranium while
G. metallireducens
degrades both uranium and plutonium.
G. metallireducens
flagella and “sniff out” metals if none are available in its location.
has genes that allow it to grow
•
Thermus brockianus,
produces a protein that breaks down hydrogen peroxide.
This protein can be added directly to industrial waste water to treat the water before it is released.
Hydrocarbon-degrading
Pseudomonas
strains were transformed with an
E. coli pro U
operon which improved the ability to grow under hyper-saline conditions allowing improved bioremediation in marine environments.
Monitored Natural way:
use of pants & microbes)
Bioaugmentation:
is the introduction of a group of natural microbial strains or a genetically engineered variant to treat contaminated soil or water.
Biostimulation
-
involves the modification of the environment to stimulate existing bacteria capable of bioremediation. This can be done by addition of various forms of rate limiting nutrients and electron acceptors such as phosphorus, nitrogen, oxygen, or carbon
Biobarriers : Acid rock drainage from hard rock mine lands is a major environmental problem that impacts both ground- and surface water throughout the Western US.
Naturally occurring aerobic and facultative bacteria which utilize dissolved oxygen in the infiltrating water and therefore maintain the reducing conditions which are necessary for pyrite (an iron sulfide) and other metal sulfides to remain bound in mineral form in water.
Mycoremediation:
Fungal Remediation
William J., and Michael A. Pallandino. Introduction to Biotechnology. San Francisco: Pearson Education, Inc., 20007 “Biobarriers and Bioremediation Collection.” Montana State University Center for Biofilm Engineering. 9 Apr. 2009,
“Phytoremediation: Using Plants To Clean Up Soils.” June 2000. United States Department of Agriculture. 18 Oct. 2007. http://www.ars.usda.gov/is/AR/archive/jun00/soil0600.htm
“Sewage Treatment.” Wikipedia: The Free Encyclopedia. 19 Oct. 2007. http://en.wikipedia.org/wiki/Sewage_treatment Kris Traver, Niana Islam And Edwin Estime 2007 Biotech group for power point creativity editing.
Center for Disease Control and Prevention. “Emergency Preparedness and Response: Bioterrorism”
http://www.redorbit.com/news/science/1945110/the_murky_picture_beneath_the_surfa ce/
http://www.youtube.com/watch?v=Bju4C5 GxeQs&feature=related