Surface activity of salt-tolerant Serratia spp. and crude oil biodegradation in saline soil

Abstract

An ideal strain for crude oil degradation in saline soils would be one with high salt-tolerance. A novel bacterial strain, Serratia sp. BF40, was isolated from crude oil contaminated saline soils. Its salt-tolerance, surface activity and ability to degrade crude oil in saline soils were evaluated. It can grow in liquid culture with NaCl concentration less than 6.0%. Its surface activity characterized as an efficient surface tension reduction, was significantly affected by salinity above 2.0%. BF40 inoculation could decrease surface tension of soil solutions and facilitate crude oil removal in soils with 0.22-1.20% salinity, but the efficiency was both significantly lower than its biosurfactant addition. The BF40 strain has a high potential for biodegradation of crude oil contaminated saline soils in view of its high surface activity and salt-tolerance, which is the first report of biosurfactant producing by the genus Serratia for petroleum degrading. We suggest that biosurfactant addition is an efficient strategy. Simultaneously, the growing status of the strain and how to boost its surface activity in saline soils should deserve further studies in order to achieve a continuous biosurfactant supply.

A newly isolated strain of Serratia sp. from an oil spillage site of Assam shows excellent bioremediation potential

“…Moreover, the non-cytotoxicity nature of the biosurfactant produced by the isolate on the primary mouse liver cell line clearly advocates its possible applicability for 80-82% +ve Ramadass et al (2018) bioremediation field trial. Even though a handful of reports are available with successful ex situ microbial bioremediation study on contaminated soil with defined bacterial strains or consortium (Morelli et al 2005;Mukherjee and Bordoloi 2011;Sangeetha and Thangadurai 2014;Patowary et al 2018;Ramadass et al 2018), but very limited reports show different members of the genus Serratia, mostly the species marcescens involved in hydrocarbon degradation (Mohanan et al 2007;Rajasekar et al 2011;Wu et al 2012;Almansoory et al 2016;Rajasekar 2017). Herein, we report a newly isolated strain belongs to the genus Serratia involved in ex situ bioremediation of petroleum-contaminated soil and water.…”

Pseudomonas aeruginosa L10: A Hydrocarbon-Degrading, Biosurfactant-Producing, and Plant-Growth-Promoting Endophytic Bacterium Isolated From a Reed (Phragmites australis)

“…The plants were harvested after 120 days and biomasses (dry weights) of plants from different treatments were measured. Meanwhile, petroleum residues in soil samples were extracted with methylene chloride and the amount of residual TPH was determined gravimetrically ( Wu et al, 2012 ).…”

Characterization and Evaluation of the Potential of a Diesel-Degrading Bacterial Consortium Isolated from Fresh Mangrove Sediment

“…The fertilizer supply causes an increase in heterotrophic and hydrocarbon-splitting bacteria and an increase in the phytoplanktonic biomass (LePetit and N'Guyen 1976 Fan et al (2013) obtained 83 % TPH removal using an exogenous pure strain and 61 % using indigenous microorganisms. Wu et al (2012) obtained more than 60 % after 270 days using P. fluorescens. All these different reduction rates are comparable to our results.…”