Genomic characterization of Enterobacter xiangfangensis STP-3: Application to real time petroleum oil sludge bioremediation.

Sustainable treatment of petroleum oil sludge still remains as a major challenge to petroleum refineries. Bioremediation is the promising technology involving bacteria for simultaneous production of biosurfactant and followed by degradation of petroleum compounds. Complete genomic knowledge on such potential microbes could accentuate its successful exploitation. The present study discusses the genomic characteristics of novel biosurfactant producing petrophilic/ petroleum hydrocarbon degrading strain, Enterobacter xiangfangensis STP-3, isolated from petroleum refinery oil sludge contaminated soil. The genome has 4,584,462 bp and 4372 protein coding sequences. Functional analysis using the RAST and KEGG databases revealed the presence of biosynthetic gene clusters linked to glycolipid and lipopeptide production and multiple key candidate genes linked with the degradation pathway of petroleum hydrocarbons. Orthology study revealed diversity in gene clusters associated to membrane transport, carbohydrate, amino acid metabolism, virulence and defence mechanisms, and nucleoside and nucleotide synthesis. The comparative analysis with 27 other genomes predicted that the core genome contributes to its inherent bioremediation potential, whereas the accessory genome influences its environmental adaptability in unconventional environmental conditions. Further, experimental results showed that E. xiangfangensis STP-3 was able to degrade PHCs by 82 % in 14 days during the bioremediation of real time petroleum oil sludge with the concomitant production of biosurfactant and metabolic enzymes, To the best of our knowledge, no comprehensive genomic study has been previously reported on the biotechnological prospective of this species.

Sustainable biological system for the removal of high strength ammoniacal nitrogen and organic pollutants in poultry waste processing industrial effluent.

The effluent generated from poultry waste processing industries contains several organic compounds such as collagen, gelatin, bovine serum albumin, carbohydrates, essential fatty acids, and so forth. This enabled the establishment of poultry waste processing industries to produce value-added products such as animal feed and organic fertilizers. During poultry waste processing, huge amounts of ammoniacal nitrogen and organic pollutants such as proteins, various carbohydrates, and fatty materials are discharged into the effluent stream which contributes to several environmental issues. Because of the shortcomings of the current conventional treatment, the present study is about with the development of a sequential bioreactor system for the effective treatment of poultry waste processing industrial effluent. Facultative anaerobe Paracoccus pantotrophus FMR19 along with the indigenous isolate Bacillus albus MN527241 obtained from clarifying sludge was used as mixed consortia for the treatment of poultry waste processing industrial effluent. The mixed microbial consortia resulted in the maximum activity of enzymes such as protease (247 U/mL) and lipase (28.266 U/mL) thereby achieving 90% of ammoniacal nitrogen reduction and 98% of COD removal within five days. Further, the confirmatory analysis of poultry effluent treatment was carried out using gas chromatography-mass spectroscopy (GC-MS), High-Performance Liquid Chromatography (HPLC), Fourier Transform Infrared Spectroscopy (FT-IR), and SDS-PAGE. Hence, the sequential bioreactor-based treatment approach has proved to be highly effective in removal of organic pollutants in the poultry waste processing industrial effluent.Implications: The poultry waste processing industrial (PWPI) effluent contains huge ammoniacal nitrogen and COD and affects the environment. Aerobic moving bed biofilm reactor and up-flow anaerobic sludge blanket reactor are in current practice and shows considerable reduction in the ammoniacal nitrogen and COD in long retention time. Therefore, there is a need of sustainable treatment process that could effectively remove the organic pollutants from the effluent in short duration. Our study focused on the application of sequential bioreactor approach for the treatment of PWPI using aerobic followed by anaerobic treatment process and observed efficient organic pollutants removal in short duration.