Anaerobic biodegradation of partially hydrolyzed polyacrylamide in long-term methanogenic enrichment cultures from production water of oil reservoirs

TY - JOUR

T1 - Anaerobic biodegradation of partially hydrolyzed polyacrylamide in long-term methanogenic enrichment cultures from production water of oil reservoirs

AU - Hu, Hao

AU - Liu, Jin Feng

AU - Li, Cai Yun

AU - Yang, Shi Zhong

AU - Gu, Ji Dong

AU - Mu, Bo Zhong

N1 - Publisher Copyright: © 2018, Springer Science+Business Media B.V., part of Springer Nature.

PY - 2018/6/1

Y1 - 2018/6/1

N2 - The increasing usage of partially hydrolyzed polyacrylamide (HPAM) in oilfields as a flooding agent to enhance oil recovery at so large quantities is an ecological hazard to the subsurface ecosystem due to persistence and inertness. Biodegradation of HPAM is a potentially promising strategy for dealing with this problem among many other methods available. To understand the responsible microorganisms and mechanism of HPAM biodegradation under anaerobic conditions, an enrichment culture from production waters of oil reservoirs were established with HPAM as the sole source of carbon and nitrogen incubated for over 328 days, and analyzed using both molecular microbiology and chemical characterization methods. Gel permeation chromatography, High-pressure liquid chromatography and Fourier-transformed infrared spectroscopy results indicated that, after 328 days of anaerobic incubation, some of the amide groups on HPAM were removed and released as ammonia/ammonium and carboxylic groups, while the carbon backbone of HPAM was converted to smaller polymeric fragments, including oligomers and various fatty acids. Based on these results, the biochemical process of anaerobic biodegradation of HPAM was proposed. The phylogenetic analysis of 16S rRNA gene sequences retrieved from the enrichments showed that Proteobacteria and Planctomycetes were the dominant bacteria in the culture with HPAM as the source of carbon and nitrogen, respectively. For archaea, Methanofollis was more abundant in the anaerobic enrichment. These results are helpful for understanding the process of HPAM biodegradation and provide significant insights to the fate of HPAM in subsurface environment and for possible bioremediation.

AB - The increasing usage of partially hydrolyzed polyacrylamide (HPAM) in oilfields as a flooding agent to enhance oil recovery at so large quantities is an ecological hazard to the subsurface ecosystem due to persistence and inertness. Biodegradation of HPAM is a potentially promising strategy for dealing with this problem among many other methods available. To understand the responsible microorganisms and mechanism of HPAM biodegradation under anaerobic conditions, an enrichment culture from production waters of oil reservoirs were established with HPAM as the sole source of carbon and nitrogen incubated for over 328 days, and analyzed using both molecular microbiology and chemical characterization methods. Gel permeation chromatography, High-pressure liquid chromatography and Fourier-transformed infrared spectroscopy results indicated that, after 328 days of anaerobic incubation, some of the amide groups on HPAM were removed and released as ammonia/ammonium and carboxylic groups, while the carbon backbone of HPAM was converted to smaller polymeric fragments, including oligomers and various fatty acids. Based on these results, the biochemical process of anaerobic biodegradation of HPAM was proposed. The phylogenetic analysis of 16S rRNA gene sequences retrieved from the enrichments showed that Proteobacteria and Planctomycetes were the dominant bacteria in the culture with HPAM as the source of carbon and nitrogen, respectively. For archaea, Methanofollis was more abundant in the anaerobic enrichment. These results are helpful for understanding the process of HPAM biodegradation and provide significant insights to the fate of HPAM in subsurface environment and for possible bioremediation.

KW - Anaerobic biodegradation

KW - Mechanism

KW - Microbial community

KW - Oil reservoir production water

KW - Partially hydrolyzed polyacrylamide

UR - http://www.scopus.com/inward/record.url?scp=85045060803&partnerID=8YFLogxK

U2 - 10.1007/s10532-018-9825-1

DO - 10.1007/s10532-018-9825-1

M3 - 文章

C2 - 29502248

AN - SCOPUS:85045060803

SN - 0923-9820

VL - 29

SP - 233

EP - 243

JO - Biodegradation

JF - Biodegradation

IS - 3

ER -