Bioremediation of Pyrene-Contaminated Soils Using Biosurfactant

Abstract

Background: Polycyclic aromatic hydrocarbons (PAHs) are persistence organic chemicals with proved carcinogenic and mutagenic hazards. These compounds are usually adsorbed in soils in vicinity of oil and gas industries. Bioremediation of PAHs contaminated soils is difficult due to hydrophobic nature of PAHs. Objectives: The main purpose of the current study was to determine the pyrene removal efficiency in synthetically contaminated soil, using biosurfactant. Materials and Methods: Four pure bacterial strains capable of pyrene degradation were isolated from contaminated soils via enrichment techniques. The soil samples were spiked with an initial pyrene concentration of 500 mg/kg and subjected to bioremediation using a mixed culture comprised of previously isolated strains, in addition to application of biosurfactant during 63 days. Results: The pyrene removal efficiency in samples containing biosurfactant, without biosurfactant and controls, were 86.4%, 59.8% and 14%, respectively, after 63 days. The difference of pyrene removal efficiency between the biosurfactant-containing samples and the ones without it was significant (P < 0.05). Conclusions: Application of rhamnolipid biosurfactant produced by Pseudomonas aeruginosa significantly improved pyrene removal in contaminated soils.

Microbial Surfactants: The Next Generation Multifunctional Biomolecules for Applications in the Petroleum Industry and Its Associated Environmental Remediation

“…The rate of fluoranthene mineralization was above 50% (using 500 μg ml −1 of alasan), with an attendant significant increase in the rate of phenanthrene mineralization by Sphingomonas paucimobilis EPA505. Similarly, Jorfi et al [120] recorded 86.4% of pyrene degradation with an initial concentration of 500 mg/kg. Complete degradation of aromatic hydrocarbon was demonstrated using a chemical surfactant (FinasolOSR-5) combined with a trehalose lipid biosurfactant [121].…”

“…Though subject to more robust research, it has been reported that rhamnolipids produced by the Pseudomonas aeruginosa strain specifically degrade hexadecane, indicating that a specific biosurfactant does degrade a particular type of hydrocarbon [108]. Rhamnolipid has been reported in the remediation of diverse kinds of hydrocarbon more than any other biosurfactant [120].…”

Microbial Surfactants: The Next Generation Multifunctional Biomolecules for Diverse Applications

“…Further, Bustamante et al [119] noted the influence of alasan on the biodegradation of polyaromatic hydrocarbons (PAHs): the rate of fluoranthene mineralization was above 50% (using 500 μg ml -1 of alasan) with an attendant significant increase in the rate of phenanthrene mineralization by Sphingomonas paucimobilis EPA505. Similarly, Jorfi et al [120] recorded 86.4% of pyrene degradation with an initial concentration of 500 mg/kg. Complete degradation of aromatic hydrocarbon was demonstrated using a chemical surfactant (FinasolOSR-5) combined with trehalose lipid biosurfactant [121].…”

“…Though subject to more robust research, it has been reported that rhamnolipids produced by Pseudomonas aeruginosa strain specifically degrade hexadecane, indicating that specific biosurfactant does degrade a particular type of hydrocarbon [108]. Rhamnolipid has been reported in the remediation of diverse kinds of hydrocarbon more than any other biosurfactant [120].…”

“…Biosurfactants have shown to play a huge role in bioremediation of hydrocarbons, metal detoxification and/or removal; and in soil washing technology [112,113,117,119,120,135,147,148,150]. Research conducted by Sachdev et al [158] reported that biosurfactants aid nutrient uptake, including root cell differentiation.…”