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Continuous
Biodegradation of High Strength Phenol by Immobilized
Bacteria in Packed-Bed Column Reactor
V.
Arutchelvan,
Professor of Civil Engineering, Annamalai University,
Annamalainagar-608002, India, Tel: +91 4144 238884, Email:
arul.au@gmail.com
V. Kanakasabai, Professor of Civil Engineering,
Annamalai University, Annamalainagar-608002, India, Tel:
+91 4144 239731, Email: vkhdce@yahoo.com
S. Nagarajan, Professor of Chemistry, Annamalai
University, Annamalainagar-608002,
India, Tel: +91 4144 238734, Email: drsn@sify.com
Phenols
are toxic to all types of organisms. Two bacterial strains
capable of utilizing phenol as a sole carbon source were
isolated from the phenol bearing industrial wastewater.
Based on the biochemical test results the organisms were
identified as Pseudomonas cepacia and Bacillus
brevis. The batch studies revealed that both organisms
were very efficient in phenol degradation. The
well-acclimatized cultures of P. cepacia and B.
brevis degraded 2500 and 1750 mgl-1 of
phenol in 144 h, respectively in batch process. In order
to enhance the rate of degradation, the isolated organisms
were immobilized in over-burnt clay cylindroids. These
cylindroids are rigid, non-toxic, non-biodegradable,
locally available, economical, easy to dispose and
eco-friendly. Phenol was continuously degraded in
packed-bed column reactor with the immobilized cells. The
effect of varying substrate concentration, Hydraulic
Retention Time (HRT) and COD removal was studied. The
organisms P.cepacia and B.brevis degraded
about 2000 and 1250 mgl-1 of phenol
concentration within 12 h of HRT, respectively. The COD
removal efficiency was about 92% for P.cepacia and
90% for B.brevis corresponding to the maximum
phenol degradation. The SEM study shows the presence of
the organisms inside the porous matrix.
Enhanced
Bioremediation of Chlorinated VOCs Using Sodium Lactate
and Dibasic Ammonium Phosphate
Mark
T. Becker,
URS Corporation, 12 Commerce Drive, Cranford, NJ 07016,
Tel: 908-709-3971, Fax: 098-272-3940, Email: mark_becker@urscorp.com.
Fayaz
Lakhwala, URS Corporation, 12 Commerce Drive, Cranford, NJ
07016, Tel: 908-709-3951, Fax: 098-272-3940, Email:
fayaz_lakhwala@urscorp.com.
Vincent L. Pace, Atlantic Richfield Company, 28100 Torch
Parkway, MC 2N, Warrenville, IL 60555, Tel: 630-836-5630,
Fax: 630-836-6336, Email: Vincent.Pace@bp.com.
Stephanie Fiorenza, Atlantic Richfield Company, 501
Westlake Park Blvd., Floor 20, Room 20.101C, Houston, TX 77079, Phone: 281-366-7484, Fax, 281-366-7094, Email:
Stephanie.Fiorenza@BP.com.
Anthony Kaufman, URS Corporation, 12 Commerce Drive,
Cranford, NJ 07016, Tel: 908-709-3905, Fax: 098-272-3940,
Email: Anthony_Kaufman@urscorp.com
Historic
discharges at a former industrial facility in New Jersey
created a plume of chlorinated ethenes in groundwater,
including trichloroethene (TCE), cis-1,2-dichloroethene
(c-DCE) and vinyl chloride (VC).
The presence of degradation products c-DCE and VC
suggest that reductive dechlorination is occurring, but
after several years of monitoring, concentrations of these
compounds have not decreased significantly.
Groundwater quality data indicated that a lack of
total organic carbon (TOC) and nutrients such as phosphate
and nitrogen may be limiting degradation processes.
A field pilot test was conducted to enhance the
on-going reductive dechlorination process.
Amendments were manually injected into the plume
weekly for a period of three months.
The amendments consisted of sodium lactate (WilClearTM)
solution and dibasic ammonium phosphate (DAP).
The sodium lactate was diluted to ease injection
and the crystalline DAP was mixed into the sodium lactate
solution. Amendments
were injected via gravity feed through tubing into
injection wells. After
each injection, a submersible pump was used to circulate
groundwater from contaminated monitoring wells into
injection wells to distribute the amendments throughout
the plume. Monitoring
data collected during this pilot test indicates that the
injections were effective at enhancing the reductive
dechlorination of target contaminants.
Concentrations of TCE decreased 86% to 96% while c-DCE
concentrations remained constant and VC production was
limited. Dissolved oxygen concentrations in all monitoring wells
within the plume decreased to 0 mg/l and redox potential
decreased from 64 mV and 209 mV to –155mV and –157 mV,
respectively. Production
of acetic and propionic acids and methane increased and
peaked 3 months after the injections ceased.
Within six months of the end of the injection
program, however, contaminant and geochemical parameters
had rebounded to pre-injection levels.
Based on the results of the sodium lactate/DAP
injections, a workplan is being prepared to inject a
longer lasting lactate-based substrate.
Bioremediation
of VPH and EPH Contaminated Groundwater Using in-situ
Submerged Oxygen Curtain (iSOC) Technology
Jacqueline
Lees, ENSTRAT,
Inc., 420 Maple Street, Marlboro, MA 01752, Tel:
508-460-6100 x19, Fax: 508-460-8115, Email: jlees@enstrat.net
James F. Begley,
MT Environmental Restoration, 24 Bay View Avenue,
Plymouth, MA 02360, Tel: 508-732-0121, Fax: 508-732-0122,
Email: jbegley@cape.com
An
iSOC bioremediation system for residual aliphatic and
aromatic volatile and extractable petroleum hydrocarbons (VPH
and EPH) contaminated groundwater was installed and
operated at a Massachusetts site. While more soluble
petroleum compounds such as BTEX are know to be readily
degraded under aerobic conditions, the degradation of
other less soluble and less bioavailable VPH and EPH
compounds is not as well understood. This case study will
examine the performance of an in-situ bioremediation
system for residual VPH and EPH contaminated groundwater
in an area downgradient of a source area excavation.
Extracellular
Electron Shuttling (EES) Compounds in Bioremediation
Student
Presenter
Caitlin
Bell
, Rm4162, 205 North Mathew Street, Civil Engineering
Building, Department of Civil and Environmental
Engineering, University of Illinois, Urbana, IL, 61801.
Tel: 217-333-8121 Email: bell5@uiuc.edu
Kevin
T. Finneran, Rm3221, 205 North Mathew Street, Civil
Engineering Building, Department of Civil and
Environmental Engineering, University of Illinois, Urbana,
IL, 61801. Tel: 217-244-7956 Email: finneran@uiuc.edu
Electron shuttling compounds are a class of molecules that
accept electrons from microbial respiratory pathways and
transfer electrons abiotically to more electronegative
electron acceptors. Recent reports suggest that
extracellular electron shuttling (EES) molecules may serve
as "redox active" agents in bioremediation
applications for organic and inorganic contaminants; humic
substances, extracellular quinones, and reactive Fe(II)
have been investigated in most detail. Our research
has focused on humic substance mediated biodegradation of
electronegative contaminants, catalyzed by prokaryotes and
eukaryotes. Recent data suggest that white and brown
rot fungi will reduce the synthetic humic analogue,
anthraquinone-2,6-disulfonate (AQDS), in the presence of
oxygen. Gloeophyllum trabeum reduced
approximately 4mM AQDS in 12 days in aerobic, aqueous
cultures, which is comparable to anaerobic cultures with
AQDS. Fe(III) was also reduced in the presence of
oxygen; Fe(II) re-oxidation kinetics were limited by
fungal biomass. The reduced EES were stable in air,
suggesting that electron transfer to contaminants such as
the explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)
may be possible in aerobic environments. To date
reductive strategies are applied in anaerobic systems;
these data indicate that fungal reductive processes may be
possible despite aerobic geochemical conditions.
Chlorinated
contaminants are also environmentally relevant electron
acceptors. To date research has focused on direct
dechlorination by specific microorganisms, which are not
present in all environments. Preliminary data
suggest that highly chlorinated compounds (tetrachloroethylene
(PCE) and trichloroethane (TCA)) may accept electrons from
the reduced EES AQDS. Bioremediation strategies for
chlorinated compounds predicated on EES will be broadly
applicable to all environments, as the microorganisms
involved have been identified in all environmental media.
Future studies will investigate EES mediated
transformation of polychlorinated biphenyls, which are
hydrophobic and inaccessible in aqueous media. EES
may overcome the mass transfer limitations by cycling
electrons from microbial respiration to adsorbed
contaminant mass, without the need for direct cell-PCB
contact.
The
Effect of Aggregate and Initial Contaminant Concentration
on the Biodegradation Rate of Total Petroleum Hydorcarbons
Ramona
Boodoosingh,
Department of Civil and Environmental Engineering, Tufts
University
, Medford,
MA 02155, Email: rboodoosingh@yahoo.com
Denise Beckles, Department of Chemistry, University of the
West Indies, St. Augustine, Trinidad, W.I.
Christopher Swan, Department of Civil and Environmental
Engineering, Tufts University, Medford,
MA 02155
Anne-Marie Desmarais, Department of Civil and
Environmental Engineering, Tufts University, Medford,
MA 02155
Bioremediation
is one of the most cost-effective, and environmentally
friendly methods to remediate many different types of
waste materials widely used by many private and public
entities. Though the parameters that affect the rate of
bioremediation differ for each project, some parameters
can be more easily controlled in the field than others.
For example, effective microbial action is crucial
to the success of bioremediation.
However, microbes can be detrimentally affected by
an initial contaminant concentration that is too high.
In addition, the type of bulking agent or aggregate
used affects the ability of the mixture to retain
moisture, the amount of drainage, aeration and ultimately
the length of time for biodegradation.
A
two-month field study was conducted in Trinidad and Tobago
on crude oil contaminated waste.
This paper will look at the effect of two
parameters, initial concentration and type of bulking
agent, on the rate of biodegradation of Total Petroleum
Hydrocarbons (TPH) in the oily waste being treated in this
tropical environment.
A nutrient-supplying bioremediation agent was used
to enhance the bioremediation process. The results of this study can assist in the design of
effective bioremediation projects in tropical
environments.
Isolation
and 16S rDNA Characterization of two Soil Bacteria Capable
of Degrading Quinalphos an Organophosphorus Insecticide
Student
Presenter
Sharungbam
Geeta Devi,
Nuclear Agriculture and Biotechnology Division, Bhabha
Atomic Research Centre. Mumbai. - 400085, Tel:
91-22-25593831, Fax: 91-22-25515050, Email:
geetasharungbam@gmail.com, sharung@sify.com
B.P. Kapadnis, Department of Microbiology, University of
Pune, Pune - 411007,
Tel:
91-20-25690643, Fax: 91-20-25690087 Email:
bpkap@hotmail.com
R.L. Deopurkar, Department of Microbiology, University of
Pune, Pune - 411007,
Tel: 91-20-25690643, Fax: 91-20-25690087, Email:
writetodeopurkar@unipune.ernet.in
S.P. Kale, Nuclear Agriculture and Biotechnology Division,
Bhabha Atomic Research Centre, Mumbai. - 400085, Tel:
91-22-25593830, Fax: 91-22-25515050, Email: skale@apsara.barc.ernet.in,
sharadkale@gmail.com
Quinalphos
is an organophosphorus insecticide and acaricide with
contact and stomach actions. No enough studies has been
done on biodegradation of quinalphos. Hence attempts were
made in the present study to isolate and identify bacteria
from insecticide contaminated soils, which are capable of
degrading quinalphos by utilizing it as a sole source of
carbon and energy. An enrichment culture technique was
used to isolate bacteria responsible for the enhanced
biodegradation of quinalphos from soil previously exposed
with various pesticides. Microscopic examination and
physiological tests were followed by 16S rDNA sequence
analysis to characterize the two bacterial isolates. One
of the isolated bacteria was identified as a Pseudomonas
sp. and another as Bacillus sp. Both Pseudomonas
sp and Bacillus sp were found to be very active
in degrading quinalphos, upto 92% degradation at
original concentration of 12mg L-1 of
quinalphos within 15days was observed.Mix cultures study
with Pseudomonas sp. and Bacillus sp. showed
83.71% degradation in10 days.
The degradation of quinalphos was maximum in the
range of pH 7.0 and pH 8.0.
With glucose and in Nutrient broth, in 10days Pseudomonas
sp. and Bacillus sp. showed
complete degradation. This shows that slight
addition of rich carbon source stimulate the degradation
of quinalphos by both Pseudomonas sp. and Bacillus
sp.. Our findings showed that indigenous microorganism are
a better means for degradation studies since Pseudomonas
sp. and Bacillus sp. which we had isolated form
the natural habitats are a potential degrader of
quinalphos. These isolates could be used to remediate
quinalphos contaminated sites.
Degradation
of Oil-Derived Hydrocarbons by Bacteria Isolated from
Oil-Contaminated Soils
F.G.
Dias, R. Filho Lima and L.R. Durrant, Departamento
de Ciências de Alimentos – Faculdade de Engenharia de
Alimentos (FEA), Universidade Estadual de Campinas (UNICAMP)
Cx. Postal: 6121, CEP:13083-862 Phone: +55 19 37882172
Email: durrant@fea.unicamp.br
Oil
and its derivatives continue to be our main energy source.
Constantly we receive information through the media
of the ecological disasters and social problems caused by
oil spills or by its derivatives.
It is estimated that of the 3.2 billion tons of oil
produced per year, 3.2 million tons enter the marine
environment. This
work had the objective to evaluate the capacity of Bacillus
circulans, Chromobacterium sp and Enterobacter
aerogenes, isolated from oil-contaminated soils, to
grow and degrade oil-derived hydrocarbons. They were
cultivated for 12 days at 30º C and 150 rpm, in a medium
containing minerals and 0.05% (final concentration) of one
of the following hydrocarbons: tridecane, tetradecane,
pristine, hexadecane, phenyldecane, phenanthrene,
naphthalene, pyrene and benzo[a]pyrene. The remaining
hydrocarbons were extracted with hexane and analyzed by
gas chromatography. Bacillus
circulans degraded tetradecane (24%), tridecane (23%),
hexadecane (24%), pristine (24%), phenyldecane (25%),
naphthalene (100%), phenanthrene (25%), pyrene (100%) and
benzo[a]pyrene (100%). A Chromobacterium
sp degraded the same hydrocarbons in the ratios of
20%; 21%; 21%; 21%; 22%;
100%; 100%;
100%; 100%
respectively. Enterobacter
aerogenes degraded 37%; 33%; 35%; 37%; 34%; 100%; 23%;
100%; 100% of the hydrocarbons present in the culture
media, respectively. Our results indicate that these three
bacterial strains have potential to be used in future
studies of oil-derivatives contaminated environments.
We
acknowledge financial support from FAPESP-SP, BRAZIL.
Degradation
of Dyes by Bacteria Isolated from the Activated Sludge of
a Textile Industry
E.
Dias-Franciscon and L.R. Durrant, Departamento
de Ciências de Alimentos – Faculdade de Engenharia de
Alimentos (FEA), Universidade Estadual de Campinas (UNICAMP)
Cx. Postal:
6121, CEP:13083-862 Phone: +55 19 37882172
Email: durrant@fea.unicamp.br
Reactive
azo dyes are widely used in the textile industries. They
are characterized by the presence of one or more azo bond,
-N=N-, which function as a chromophoric group. Under usual
dyeing conditions these dyes do not bind completely to the
fibers resulting in colored effluents.
Dye removal is desired, not only by esthetic
reasons, but also because many azo dyes and their derived
products are toxics to aquatic life and mutagenic to
humans. Although activated sludge process has been
extensively used by the textile industries this treatment
is not effective and these dyes are adsorbed by the
biomass, being later disposed in landfills, causing
contamination of these wide areas.
Trying
to solve these problems, three bacterial strains were
isolated from activated sludge of textile industries near
Campinas (SP, Brazil). Isolates were cultivated with
different dyes: Reactive azo-dye Remazol Red RR (C.I. RBN
198) and Remazol Reactive Blue (C.I. RB 220) and
degradation of the dyes was determined by UV-visible
spectrophotometry and confirmed by liquid chromatography
and also COD reduction (Chemical Oxygen Demand). Complete
degradation of RBN 198 and RB 220 was found after 24 hs
and 168 hs, respectively, by Trichococcus
sp. and COD reduction was 41 and 68%, respectively. In the case of Enterobacter
sp, RBN 198 dye was 95 % and RB 220 completely
degraded, while COD was found to be 76 and 63 %
respectively. A Bacillus
sp degraded 75% of RB 220 and 84% of the RBN used,
with COD reductions of 85 and 88%, respectively.
The
ability to decolorize these dyes and reduce of COD by
these strains, suggest that they may have potential to be
applied in the treatment of effluents and sites
contaminated by dyes.
We
acknowledge financial support from CNPQ - BRAZIL.
Physiological
Approaches to Increase Molar Hydrogen Yield in Anaerobic,
Fermentative Bacterial Cultures
Student
Presenter
Jennifer
L. Hatch,
Environmental Engineering and Science Program, Civil and
Environmental Engineering, University of Illinois, 205
North Mathews Avenue, Urbana, IL 61801, Tel: 217-333-8121,
Email: jhatch2@uiuc.edu
Kevin
T. Finneran, Assistant Professor, Environmental
Engineering and Science Program, Civil and Environmental
Engineering, University of Illinois, 3221 Newmark
Laboratory, 205 North Mathews Avenue, Urbana, IL 61801,
Tel: 217-244-7956, Email: finneran@uiuc.edu
Most approaches to increase
hydrogen production focus on reactors without regard to
increasing the hydrogen yield per mol of substrate
consumed. Optimized
reactor designs are necessary; however, increasing the
molar hydrogen yield is necessary before hydrogen-based
fuel strategies can be commercially applied in a
cost-effective manner.
This research aims to circumvent organic acid
synthesis and increase hydrogen production by altering the
electron transfer pathway in fermentative bacteria.
Carbon and hydrogen metabolisms of a fermentative
pure culture (Clostridium
beijerinckii) will be altered along with culture
conditions to develop strains of microorganisms and
co-cultures which will over-produce hydrogen.
This approach in the
over-production of hydrogen is alteration of the redox
potential of the proton/H2 couple so that
electron transfer to protons becomes favorable relative to
organic acid synthesis.
By utilizing electron transfer molecules such as
quinones to increase the relative redox potential of the H+/H2
redox couple, it is possible to cycle electrons from
glucose oxidation through the electron carriers to
hydrogenase and protons; this circumvents the organic acid
synthesis pathway and increases hydrogen yield.
C.
beijerinckii was grown anaerobically in glucose-rich
medium in order to perform resting cell suspensions under
non-growth conditions in anaerobic bicarbonate buffer.
250 mM
biologically reduced AQDS (AH2QDS) increased
hydrogen production by 50% above the expected
stoichiometry for C.
beijerinckii. Adding
5-100nM NAD+ increased the rate of hydrogen
production as well as the yield by 75% for C.
beijerinckii. With
increasing concentrations of AH2QDS, hydrogen
production was seen to increase, but with addition of NAD+,
decreased concentrations proved to increase hydrogen
yield.
The extent of AQDS and
acetate cycling between Geobacter
metallieducens (GS-15) grown on AQDS media and C.
beijerinckii will be evaluated on batch and reactor
scales while monitoring hydrogen production.
The effects of several different environmental
samples such as agricultural waste and digester fluid for
substrate will also be investigated in a reactor using
pure and mixed cultures.
Ultimately, hydrogen from this process will be
recovered for use in fuel cells.
Enhancing
Bioremediation of DNAPL TCE in Carbon-Poor, Slightly
Oxidizing Groundwater within Glacial Soils
Lucas
A. Hellerich,
Ph.D., P.E., Metcalf & Eddy, Inc., 860 North Main
Street Extension, Wallingford, CT 06492, Tel:
203-269-7310, Fax: 203-269-8788, Email: lucas.hellerich@m-e.aecom.com
John
L. Albrecht, L.E.P., Metcalf & Eddy, Inc., 860 North
Main Street Extension, Wallingford, CT 06492, Tel:
203-269-7310, Fax: 203-269-8788, Email: john.albrecht@m-e.aecom.com
Dave Hart, C/O Noranda Aluminum P.O. Box 70, New Madrid,
MO 63869, Tel: 573-643-6763, Fax: 573-643-6715,
Email: Dave.Hart@falconbridge.com
This
paper describes a field pilot study of enhanced
bioremediation (reductive dechlorination) of
trichloroethene (TCE) at a site located in western
Connecticut. Geology
at the test location consisted of glacial till overlying
weathered gneissic bedrock.
The estimated static groundwater velocity was 0.17
ft/day. The
concentration of TCE in the study area varied spatially,
but was up to 768 mg/L (~ 70% solubility of TCE),
indicating the presence of DNAPL.
Low levels of the degradation products cis-1,2-dichloroethene
(cis-1,2-DCE)
(330 µg/L), vinyl chloride (85 µg/L), and ethene (7.7 µg/L)
were detected, suggesting the occurrence of microbially-mediated
reductive dechlorination.
Groundwater chemistry was characterized as follows:
circum-neutral pH; slightly oxidizing (~ 2 mg/L dissolved
oxygen); low total organic carbon (TOC) content (2.7 mg/L
TOC); moderate sulfate (43 mg/L); and measureable methane
(45 µg/L) and dissolved hydrogen (19 nM), indicating the
potential for methanogenic activity.
Methanogenic bacteria were detected at moderate
levels. Dehalococcoides
spp. bacteria, the only known bacteria capable of
completely reducing TCE to ethene, were also detected, but
at levels several orders of magnitude lower than the
methanogens.
A
dilute solution (10% – 15%) of EOSTM
emulsified soybean oil, amended with a bromide tracer, was
injected into the subsurface, providing a source of carbon
and reducing power for the naturally-occurring microbial
populations. The
injectate was chased with potable water to facilitate
distribution in the saturated subsurface.
Reducing conditions, characterized by negative
oxidation-reduction potential and decreased DO levels,
were achieved within several weeks of the injection event.
The distribution of EOSTM was evaluated
using TOC and bromide concentrations, and indicated the
presence of preferential flow paths in the subsurface.
Aqueous TOC concentrations ranged from 22 mg/L to
17,000 mg/L within the test volume.
Chlorinated ethenes, geochemical parameters,
electron acceptors, and microbial populations were
measured as a function of time.
An evaluation of the efficacy of enhancing
reductive dechlorination at the site was performed.
The
Biodegradation of Petroleum Hydrocarbons in Three
Ecuadorian Crude Oils
Bo
Liu,
NewFields Environmental Forensics Practice, LLC, 100
Ledgewood Place, Suite 302, Rockland, MA 02370, Tel: (781)
681-5040, Fax: (781) 681-5048, Email: bliu@newfields.com
Gregory
S. Douglas, NewFields Environmental Forensics Practice,
LLC, 100 Ledgewood Place, Suite 302, Rockland, MA 02370,
Tel: (781) 681-5040, Fax: (781) 681-5048, Email: gdouglas@newfields.com
Jeffery H. Hardenstine, NewFields Environmental Forensics
Practice, LLC, 100 Ledgewood Place, Suite 302, Rockland,
MA 02370, Tel: (781) 681-5040, Fax: (781) 681-5048, Email:
jhardenstine@newfields.com
When
crude oil is released to the environment its hydrocarbon
composition begins to change due to
physical/chemical/biological process collectively known as
weathering. Physical
weathering such as evaporation and water washing may occur
relatively rapidly, however the most important process
related to the long term degradation and removal of the
oil from the environment is biodegradation.
A laboratory study has been performed to evaluate
the compositional changes and biodegradation potential of
three crude oils. Nutrients
and naturally occurring bacteria were added to crude oil
samples from Ecuador and incubated in the laboratory at 30°C
for up to twenty weeks.
The
bacterial inocula, used in this study were developed with
indigenous bacteria from soils in petroleum producing
regions in Ecuador. These
tests showed that volatile hydrocarbons, including
gasoline range organics (GRO, C5-C12
range TPH) such as benzene, toluene, ethylbenzene and
xylenes (BTEX), in the crude oil were degraded by
naturally occurring bacteria within 1-7 days.
A second group of compounds, semi-volatile
hydrocarbons, were also measured in the crude oil.
This group of compounds includes petroleum
hydrocarbons such as diesel range organics (DRO, C10-C28
range TPH) and the USEPA 16 priority pollutant polycyclic
aromatic hydrocarbons (PAH) such as naphthalene, fluorene,
phenanthrene and chrysene.
Laboratory tests showed that semi-volatile
hydrocarbons were significantly degraded within 2 weeks.
Approximately 84%-89% of the DRO and 97% of the
total USEPA Priority Pollutant PAHs within the
semivolatile range of crude oil were biodegraded after
twenty weeks. Crude
oil residues found in site soils from Ecuador appear to be
degraded to a degree similar to that documented in this
laboratory study. These
similarities indicate that significant biodegradation has
occurred—either naturally or as the result of
remediation activities—at these sites.
Behavior
of Autotrophic Perchlorate Reducing Bacteria and Analysis
of Royal Demolition Explosive [RDX] in Water by High
Performance Liquid Chromatography, HPLC/UV
José Roberto Rivera-Negrón,
University of Puerto Rico - Mayagüez Campus, Chemical
Engineering Department and Chemistry Department, PO Box
5692, Mayaguez, PR 00681, Tel: 787-432-9240, Email:
negron.jr@gmail.com
Ashish K Sahu, University of Massachusetts, Civil
and Environmental Engineering, 18 Marston Hall, Amherst,
MA, 01003, Tel: 413-687-3347, Email: aksahu@acad.umass.edu
Sarina Ergas, University of Massachusetts, Civil and
Environmental Engineering, 18 Marston Hall, Amherst, MA,
01003, Tel: 413-545-3424, Email: ergas@ecs.umass.edu
Perchlorate, (ClO4-)
contamination in ground and surface waters can cause
serious human health effects, severe ecological and
environmental consequences. Perchlorate can disrupt
thyroid function and may impact fetal and newborn
development, resulting in changes in behavior and learning
capability. Many times ClO4- is a
co-contaminant with RDX. This research investigated
biological reduction of perchlorate and RDX by autotrophic
sulfur oxidizing bacteria. ClO4- was
analyzed with Ion Chromatography (IC). RDX can enter the
water from disposal of waste water from Army ammunitions
plants, and it can enter water or soil from spills or
leaks from improper disposal at hazardous waste sites. RDX
can cause seizures in humans and animals when large
amounts are inhaled or ingested. The Environmental
Protection Agency (EPA) has determined that RDX is a
possible human carcinogen (Class C). The RDX was measured
with High Performance Liquid Chromatography (HPLC) with a
Photo Diode Array Detector (PDA). The experiment was
conducted following the Method 8330 from EPA. The bacteria
population change was determined with a Bicinchoninic Acid
(BCA) Protein Assay. Regarding the bacteria population, we
saw an increase from 190 µg/ml to 270 µg/ml protein in
the solution over 20 days.
Perchlorate was degraded from 9.2 ppm to 8.6 ppm.
In the case of RDX alone with the bacteria, RDX degraded
from an initially 475 ppb to below the MDL (about 5 ppb).
Also the RDX, perchlorate and the bacteria, the
concentration of RDX was decreased from 467 ppb to lower
than the MDL. In conclusion the setup for the RDX analysis
was accomplished and the bacteria can degrade both
contaminants, ClO4- and RDX.
Natural
Gene Transfer to Develop Resistance to Metal Toxicity in
Microbial Communities at the Oak Ridge Reservation Field
Research Center
Safiyh Taghavi, Biology
Department, Brookhaven National Laboratory, 40 Bell
Avenue, Bldg 463, Upton, NY 11973, Tel: 631-344-5306, Fax:
631-344-3407, E-mail: taghavis@bnl.gov
David Moreels, Biology Department, Brookhaven National
Laboratory, 40 Bell Avenue, Bldg 463, Upton, NY 11973,
Tel: 631-344-4924, Fax: 631-344-3407, E-mail: dmoreels@bnl.gov
Craig Garafola, Biology Department, Brookhaven
National Laboratory, 40 Bell Avenue, Bldg 463, Upton, NY
11973, Tel: 631-344-4924, Fax: 631-344-3407, E-mail: cgarafol@bnl.gov
Garry Crosson, Environmental Science
Department, Brookhaven National Laboratory, 34 Railroad
Street, Bldg 830, Upton, NY 11973Y, Tel: 631-344-4921,
Fax: 631-344-4486, E-mail: gcrosson@bnl.gov
Jeffrey P. Fitts, Environmental Science
Department, Brookhaven National Laboratory, 34 N Railroad
Street, Bldg 830, Upton, NY 11973, Tel: 631-344-2777, Fax:
631-344-4486, E-mail: fitts@bnl.gov
Daniel van der Lelie (Principal Investigator),
Biology Department, Brookhaven National Laboratory, 40
Bell Avenue, Bldg 463, Upton, NY 11973, Tel: 631-344-5349,
Fax: 631-344-3407, E-mail: vdlelied@bnl.gov
The Field Research Center (FRC)
at Oak Ridge National Lab is characterized by mixed
pollution consisting of heavy metals, radionuclides and
nitrate. The remediation of toxic metals depends on a
method of in situ containment that decreases their
mobility and bioavailability, which in the case of uranium
is based on its reduction by dissimilatory sulfate and
iron reducing organisms. However, the presence of high
levels of heavy metals and nitrate can inhibit their
activities: especially high levels of nitrate, used by
anaerobic bacteria as an electron acceptor, will decrease
the efficiency of U(VI) and metal reduction. Under these
conditions a two-step approach is required. In a first
step nitrate is removed via the activity of nitrate
reducing bacteria, followed by a second step of U(VI) and
metal reduction/precipitation. Unfortunately, the activity
of nitrate reducing bacteria is inhibited under conditions
of elevated heavy metals. It was therefore hypothesized
that inoculation with nitrate reducing organisms, which
were genetically engineered with heavy metal resistant
genes, might improve nitrate reduction, either via
establishment of the inoculum or via horizontal gene
transfer of the heavy metal resistance determinant into
the indigenous community of nitrate reducing bacteria.
In order to test our
hypotheses, in situ simulating lab-scale column
experiments were set-up with soil samples taken from the
FRC site and percolated with a mineral medium contaminated
with nickel. The columns were bio-augmented with Pseudomonas
DM-Y2, which was engineered with nre isolated from
heavy metal resistant Cupriavidus metallidurans
31A. The efficiency of nitrate reduction and U(VI)
reduction by the established complex microbial community
was evaluated by following the microbial community
dynamics and by chemical analysis of the column effluents.
In function of time the population was characterized by
most probable counts of nitrate, sulfate and iron reducing
organisms. The fraction of nickel resistant organisms was
counted after spread plating on nickel containing
selective media. Sequencing and cloning of the 16S rDNA
genes of the eubacterial population was used to identify
the predominant community members. Spectroscopic
techniques were used to determine sulfate and nitrate
concentrations, while iron, nickel and uranium
concentrations and speciation were determined by ICP-MS
and EXAFS. Based on our data we concluded that under
conditions of Ni selection a shift in community
composition occurred from a population dominated by β
and γ-proteobacteria to a community dominated by
Ni-resistant, nitrate reducing Arthrobacter, Pseudomonas
and Sphingomonas species. In addition to
nitrate reduction we also observed the establishment of a
second redox-zone in which increased sulfate and U(VI)
reduction occurred, even in the presence of nickel.
The
Effect of PCB Partitioning between Aqueous and Organic
Phases on Rate and Extent of Biodegradation
Student
Presenter
Lars
Rehmann,
Department of Chemical Engineering, Queen’s University,
Kingston, Ontario, Canada, Tel:
613- 533-6000, Ext. 75170, Fax: 613-533-6637, Email:
lrehmann@chee.queensu.ca
Andrew
J. Daugulis, Department of Chemical Engineering, Queen’s
University, Kingston, Ontario, Canada, Tel:
613-533-2784,
Fax: 613-533-6637, Email: andrew.daugulis@chee.queensu.ca
Octanol/water
partitioning coefficients of environmentally significant
compounds such as polychlorinated biphenyls (PCB) or
polycyclic aromatic hydrocarbons (PAH) are in the order of
104 to 105. This might result in
extremely low aqueous phase concentrations of these
compounds if an organic phase is present at contaminated
sites. It was
the scope of this study to investigate whether or not the
presence of an, otherwise non-toxic, organic phase can
become the limiting factor in aerobic PCB degradation.
Burkholderia
xenovorans
LB400 is the most studied organism for aerobic PCB
degradation, and its degradation kinetics for biphenyl
were studied in a two-phase partitioning (TPPB). The use
of a TPPB allowed it to operate a bioreactor at constantly
low aqueous phase substrate concentrations near the half
saturation concentration of the Monod model. The specific
growth rate and the half saturation constant of the Monod
model were estimated to be mmax
= 0.25 h-1 and KS = 0.0001 g L-1,
with a yield coefficient of YX/S = 0.48 g
biomass per g biphenyl. The estimated value of KS
is at the low end of the typical values for bacteria,
which is expected for an organism utilizing a hydrophobic
substrate. PCBs are degraded via the biphenyl pathway by
the same enzymes as biphenyl, allowing the assumption that
the half saturation constant for PCBs is in a similar
range, most likely higher than the one for biphenyl.
Hence, it was expected that low concentrations of PCBs
could not be degraded in the presence of a large organic
fraction. Experiments with a constant amount of PCBs and
different amounts of two organic solvents showed that PCBs
could only be degraded in the presence of a small organic
fraction. The concentration in the aqueous phase became
too low for successful biodegradation as soon as the
organic fraction reached a certain level. It can therefore
be concluded that reduced bioavailability of PCBs due to
partitioning in an organic fraction can be the limiting
factor during biodegradation of PCBs.
Degradation
of 2-aminobenzenesulfonate by a Two-Membered Bacterial
Consortium
Student
Presenter
Poonam
Singh,
Biotechnology laboratory, Department of Chemistry, I.I.T., Kanpur- 208016,
India, Tel: + 91- 512-2597104, Fax: 91-512-2597436, Email:
singhpoonam3012@rediffmail.com, spoonam@iitk.ac.in
Vivek
Singh Chauhan, Biotechnology laboratory, Department of
Chemistry, I.I.T., Kanpur- 208016, India, Tel: + 91-
512-2597104, Fax: 91-512-2597436, Email:
viveksc@iitk.ac.in
Leela Iyengar, Biotechnology laboratory, Department of
Chemistry, I.I.T., Kanpur- 208016, India, Tel: + 91-
512-2597104, Fax: 91-512-2597436, Email: leela@iitk.ac.in
Aminobenzenesulfonates
(ABS) are used in the production of dyes, ion exchange
resins, optical brightners and as additives to products
like ink and engine oils. Consequently they are present in
effluents from these production processes and find their
way to rivers and surface waters. Due to their xenobiotic
and highly polar nature, biodegradation of
aminobenzenesulfonates require specialized bacterial
strains. Reports on 2-ABS degradation, by either mixed or
pure bacterial cultures, are very scarce. The present
study is on the development of two-membered bacterial
consortium for 2-ABS degradation.
Among
several sources of inocula used in this study, enrichment
could be developed only from the sludge derived from
wastewater treatment plant for organic chemical
manufacturing unit. This indicates that 2-ABS degrading
organisms are still very rare in environment. Several
transfers, over a period of six months, led to the
development of two-membered consortium. During growth in
batch culture, 2-ABS could be used as the sole carbon,
energy, nitrogen and sulfate source. The relative number
of one of these strains was much higher than the other one
in 2-ABS grown culture. Although stiochiometric release of
sulfate was observed, ammonia recovery was less than 40%
for 800mg/L of 2-ABS. Mineralization was indicated by high
TOC removals. Degradation was observed even upto 1500mg/L
2-ABS. The culture was highly specific for 2-ABS, as none
of other susbstituted benzene sulfonates could be
degraded. Thus it seems that mixtures of aromatic
sulfonates can only be degraded by mixed bacterial
consortia, which harbour diverse genes for congeneric
substrates.
The
role of these bacterial strains in 2-ABS degradation and
their characterization by 16S rDNA sequence analysis are
presently carried out.
Biodegradation
of Weathered Oil in Soils with a Long History of TPH
Contamination
Talaat
Balba, Ph.D. Conestoga-Rovers & Associates, 2055
Niagara Falls Blvd, Niagara Falls, NY 14303, Tel:
716-297-6150, Fax: 716-297-2265, Email:
tbalba@craworld.com
Sophia Dore, Ph.D. Conestoga-Rovers & Associates, 2055
Niagara Falls Blvd, Niagara Falls, NY 14303, Tel:
716-297-6150, Fax: 716-297-2265, Email: sdore@craworld.com
Donald Pope, B.S. Conestoga-Rovers & Associates, 2055
Niagara Falls Blvd, Niagara Falls, NY 14303 Tel:
716-297-6150, Fax: 716-297-2265, Email: dpope@craworld.com
Jennifer
Smith,
M.S. Conestoga-Rovers & Associates, 2055 Niagara Falls
Blvd, Niagara Falls, NY 14303 Tel: 716-297-6150, Fax:
716-297-2265, Email: jjsmith@craworld.com
Alan
Weston, Ph.D. Conestoga-Rovers & Associates, 2055
Niagara Falls Blvd, Niagara Falls, NY 14303 Tel:
716-297-6150, Fax: 716-297-2265, Email: aweston@craworld.com
Sites
with a long history of exposure to petroleum hydrocarbons
contain mainly long chain hydrocarbons or “weathered
oil”. This
is because petroleum is a complex mixture of many organic
compounds and these compounds biodegrade at different
rates. Under
aerobic conditions the shorter hydrocarbon chains
biodegrade first and the longer chains are more
recalcitrant.
Long
chain hydrocarbons are less soluble in water and more like
tar in consistency than the shorter chain hydrocarbons, so
a major problem with the degradation of these compounds is
that bacteria that break down hydrocarbons do not come
into contact with them. These compounds are not bioavailable and therefore do not
biodegrade.
A
petroleum refinery that has been active for many years has
a large amount of weathered oil the surrounding soil and
groundwater. A
treatability study was performed on samples from the Site
to determine whether conditions could be manipulated to
stimulate the biodegradation of the weathered oils. Several sets of microcosms containing soil and groundwater
were set up. Along
with nutrients and an oxygen source, a biodegradable
surfactant was added to some of the sets in order to
determine whether increasing the bioavailability of the
hydrocarbons would enhance their degradation.
After
the microcosms were set up, there was an initial increase
in hydrocarbons in the aqueous phase and a decrease in
hydrocarbons in the soil phase in the microcosms that had
received surfactant.
This change was due the surfactant solubilizing
hydrocarbons out of the soil and into the water.
As the experiment progressed, however, a decline in
hydrocarbon levels in both soil and groundwater was
observed.
It
was determined that by manipulating the conditions and
solubilizing the hydrocarbons, biodegradation of weathered
oils could be stimulated.
Hydrocarbons could be removed from soils that had
contained these weathered oils for many years without any
appreciable degradation.
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