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Title: Functional Stability Of A Mixed Microbial Consortia Producing PHA From Waste Carbon Sources

Abstract

Polyhydroxyalkanoates (PHAs), naturally-occurring biological polyesters that are microbially synthesized from a myriad of carbon sources, can be utilized as biodegradable substitutes for petroleum-derived thermoplastics. However, current PHA commercialization schemes are limited by high feedstock costs, the requirement for aseptic reactors, and high separation and purification costs. Bacteria indigenous to municipal waste streams can accumulate large quantities of PHA under environmentally controlled conditions; hence, a potentially more environmentally-effective method of production would utilize these consortia to produce PHAs from inexpensive waste carbon sources. In this study, PHA production was accomplished in sequencing batch bioreactors utilizing mixed microbial consortia from municipal activated sludge as inoculum, in cultures grown on real wastewaters. PHA production averaged 85%, 53%, and 10% of the cell dry weight from methanol-enriched pulp-and-paper mill foul condensate, fermented municipal primary solids, and biodiesel wastewater, respectively. The PHA-producing microbial consortia were examined to explore the microbial community changes that occurred during reactor operations, employing denaturing gradient gel electrophoresis (DGGE) of 16S-rDNA from PCR-amplified DNA extracts. Distinctly different communities were observed both between and within wastewaters following enrichment. More importantly, stable functions were maintained despite the differing and contrasting microbial populations.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Idaho National Laboratory (INL)
Sponsoring Org.:
DOE - NE
OSTI Identifier:
911930
Report Number(s):
INL/CON-05-01051
TRN: US200801%%377
DOE Contract Number:
DE-AC07-99ID-13727
Resource Type:
Conference
Resource Relation:
Conference: 28th Symposium on Biotechnology for Fuels and Chemicals,Nashville, TN,04/30/2006,05/03/2006
Country of Publication:
United States
Language:
English
Subject:
59 - BASIC BIOLOGICAL SCIENCES; BACTERIA; BIOREACTORS; BIOTECHNOLOGY; CARBON SOURCES; COMMERCIALIZATION; COMMUNITIES; DNA; ELECTROPHORESIS; FUNCTIONALS; MUNICIPAL WASTES; POLYESTERS; PURIFICATION; REACTOR OPERATION; SLUDGES; STABILITY; THERMOPLASTICS; WASTES; activated sludge; denaturing gradient gel electrophoresis; DGGE; feedstock; mixed consortia; polyhydroxyalkanoates; wastewater

Citation Formats

David N. Thompson, Erik R. Coats, William A. Smith, Frank J. Loge, and Michael P. Wolcott. Functional Stability Of A Mixed Microbial Consortia Producing PHA From Waste Carbon Sources. United States: N. p., 2006. Web.
David N. Thompson, Erik R. Coats, William A. Smith, Frank J. Loge, & Michael P. Wolcott. Functional Stability Of A Mixed Microbial Consortia Producing PHA From Waste Carbon Sources. United States.
David N. Thompson, Erik R. Coats, William A. Smith, Frank J. Loge, and Michael P. Wolcott. Sat . "Functional Stability Of A Mixed Microbial Consortia Producing PHA From Waste Carbon Sources". United States. doi:. https://www.osti.gov/servlets/purl/911930.
@article{osti_911930,
title = {Functional Stability Of A Mixed Microbial Consortia Producing PHA From Waste Carbon Sources},
author = {David N. Thompson and Erik R. Coats and William A. Smith and Frank J. Loge and Michael P. Wolcott},
abstractNote = {Polyhydroxyalkanoates (PHAs), naturally-occurring biological polyesters that are microbially synthesized from a myriad of carbon sources, can be utilized as biodegradable substitutes for petroleum-derived thermoplastics. However, current PHA commercialization schemes are limited by high feedstock costs, the requirement for aseptic reactors, and high separation and purification costs. Bacteria indigenous to municipal waste streams can accumulate large quantities of PHA under environmentally controlled conditions; hence, a potentially more environmentally-effective method of production would utilize these consortia to produce PHAs from inexpensive waste carbon sources. In this study, PHA production was accomplished in sequencing batch bioreactors utilizing mixed microbial consortia from municipal activated sludge as inoculum, in cultures grown on real wastewaters. PHA production averaged 85%, 53%, and 10% of the cell dry weight from methanol-enriched pulp-and-paper mill foul condensate, fermented municipal primary solids, and biodiesel wastewater, respectively. The PHA-producing microbial consortia were examined to explore the microbial community changes that occurred during reactor operations, employing denaturing gradient gel electrophoresis (DGGE) of 16S-rDNA from PCR-amplified DNA extracts. Distinctly different communities were observed both between and within wastewaters following enrichment. More importantly, stable functions were maintained despite the differing and contrasting microbial populations.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Apr 01 00:00:00 EST 2006},
month = {Sat Apr 01 00:00:00 EST 2006}
}

Conference:
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