Biostimulation of Indigenous Microbial Community for Bioremediation of Petroleum Refinery Sludge

Abstract

Nutrient deficiency severely impairs the catabolic activity of indigenous microorganisms in hydrocarbon rich environments (HREs) and limits the rate of intrinsic bioremediation. The present study aimed to characterize the microbial community in refinery waste and evaluate the scope for biostimulation based in situ bioremediation. Samples recovered from the wastewater lagoon of Guwahati refinery revealed a hydrocarbon enriched [high total petroleum hydrocarbon (TPH)], oxygen-, moisture-limited, reducing environment. Intrinsic biodegradation ability of the indigenous microorganisms was enhanced significantly (>80% reduction in TPH by 90 days) with nitrate amendment. Preferred utilization of both higher- (>C30) and middle- chain (C20-30) length hydrocarbons were evident from GC-MS analysis. Denaturing gradient gel electrophoresis and community level physiological profiling analyses indicated distinct shift in community’s composition and metabolic abilities following nitrogen (N) amendment. High throughput deep sequencing of 16S rRNA gene showed that the native community was mainly composed of hydrocarbon degrading, syntrophic, methanogenic, nitrate/iron/sulfur reducing facultative anaerobic bacteria and archaebacteria, affiliated to γ- and δ-Proteobacteria and Euryarchaeota respectively. Genes for aerobic and anaerobic alkane metabolism (alkB and bssA), methanogenesis (mcrA), denitrification (nirS and narG) and N2 fixation (nifH) were detected. Concomitant to hydrocarbon degradation, lowering of dissolve O2 and increase in oxidation-reduction potential (ORP) marked with an enrichment of N2 fixing, nitrate reducing aerobic/facultative anaerobic members [e.g., Azovibrio, Pseudoxanthomonas and Comamonadaceae members] was evident in N amended microcosm. This study highlighted that indigenous community of refinery sludge was intrinsically diverse, yet appreciable rate of in situ bioremediation could be achieved by supplying adequate N sources.

Changes in degrading ability, populations and metabolism of microbes in activated sludge in the treatment of phenol wastewater

“…29 Spirochaetae is seldom studied or discovered in the degradation of aromatic hydrocarbons; however, it took up 5% in a microcosm of petroleum renery sludge, which is consistent with our results. 30 In order to deepen the understanding on microbe dynamics, a hierarchical heatmap analysis was performed based on microbial community proles at the genus level. According to Fig.…”

Pseudomonas fluorescens: A Bioaugmentation Strategy for Oil-Contaminated and Nutrient-Poor Soil

“…Figure 4 shows that the bacteria population is larger for treatments Y4 > Y5 > Y3, which could be due to the addition of P. fluorescens as a bioaugmentation system. Various studies have shown that the significant increase in viable bacterial counts is due to the enrichment of the soil because of the nutrient biostimulation [ 68 , 69 , 70 , 71 , 72 ].…”

Characterization of fermentation liquid from mangrove leaves Avicennia marina and its inhibitory potential for bacterium causing ice-ice disease

“…Mangrove leaves A. marina used as indigenous microorganisms (IMO) source, is group of innate microbial consortium that inhabits the soil and the surface of all living things inside and outside (Umi & Saria, 2006), and easily available in that environment (Kumar & Gopal, 2015). IMO has potentiality in nitrogen fixation, increase soil fertility, phosphates solvent, and increase plant growth (Umi & Saria, 2006), bioremediation (Kao et al, 2016;Sarkar et al, 2016;Kumar & Gopal, 2015), and protect host from pathogenic microorganism (Kumar & Gopal, 2015), biactivator (Mirwandono et al, 2018), increase the availability of nutrients for host (Sakimin et al, 2017;Suyanto & Irianto, 2016), and as fermentation agent (Anyanwu et al, 2015).…”