Transcript Permeable Barrier Configuration

Bioaugmentation and
Biostimulation
Shu-Chi Chang, Ph.D., P.E., P.A.
Assistant Professor1 and Division Chief2
1Department of Environmental Engineering
2Division of Occupational Safety and Health,
Center for Environmental Protection and Occupational Safety and Health
National Chung Hsing University
Wednesday, May 23, 2007
Bioaugmentation (BA)
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Addition of microorganisms to enhance a specific biological
activity
Has been demonstrated to be beneficial on PHCs and
chlorinated compounds.
Mass transport: Microbial attachment and contaminant mobility.
Hard to discern effects of BA from simultaneous biostimulation
caused by nutrient addition.
May be useful in case of pollutant toxicity of lack of appropriate
microorganisms
Success relies on an understanding of (1) bioavailability of
contaminants, (2) survival and activity of added microorganisms
or its genetic materials, and (3) general environmental
conditions
Bioreactive Barriers
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Need a side-by-side comparison of
bioaugmentation and biostimulation
Dehalococcoids and Desulfuromonas
were quantitatively monitored
Real-time PCR and Terminal Restriction
Fragment Length Polymorphism were
employed
Introduction
Dehalococcoids spp.,
Dehalococcoids ethenogens
PCE,TCE  Ethene
Desulfuromonas spp.
PCE,TCE  cis - DCE
KB-1
PCE  VC, Ethene
Methods
Methods
Results
Results
Results
Results
Results
Results
Summary
Bioaugmentation is based on the ecological principle that natural
microorganisms have not established a competitive 'niche' (function) for
the contaminant. An inoculum has a high rate of success to establish as
long as the contaminant is present, and the niche is unoccupied.
Requirement for some type of 'tracking mechanism' to establish that the
degradation is due to biodegradative activity associated with the inoculum.
---> development of specific metabolic (e.g. Biolog), genetic (e.g. DNA
and RNA probes) or physiological (e.g. FAME) fingerprints for the
inoculum which can be recognized against 'autochthonous'
microorganisms
---> development of bioluminescence probes; e.g luciferase genes
coupled to biodegradative genes. Induction of the biodegradative enzymes
by long chain aldehydes and alcohols will trigger luciferase expression:
ATP + NADH luciferase
ADP + NAD+ + l