Bioresource Technology, Vol.207, 24-30, 2016
Simultaneous inhibition of sulfate-reducing bacteria, removal of H2S and production of rhamnolipid by recombinant Pseudomonas stutzeri Rhl: Applications for microbial enhanced oil recovery
Sulfate-reducing bacteria (SRB) are widely existed in oil production system, and its H2S product inhibits rhamnolipid producing bacteria. In-situ production of rhamnolipid is promising for microbial enhanced oil recovery. Inhibition of SRB, removal of H2S and production of rhamnolipid by recombinant Pseudomonas stutzeri Rhl were investigated. Strain Rhl can simultaneously remove S-2 (> 92%) and produce rhamnolipid (> 136 mg/l) under S-2 stress below 33.3 mg/l. Rhl reduced the SRB numbers from 109 to 105 cells/ml, and the production of H2S was delayed and decreased to below 2 mg/l. Rhl also produced rhamnolipid and removed S-2 under laboratory simulated oil reservoir conditions. High-throughput sequencing data demonstrated that addition of strain Rhl significantly changed the original microbial communities of oilfield production water and decreased the species and abundance of SRB. Bioaugmentation of strain Rhl in oilfield is promising for simultaneous control of SRB, removal of S-2 and enhance oil recovery. (C) 2016 Elsevier Ltd. All rights reserved.