一株石油烃降解菌的细胞疏水性及其乳化性质

【目的】从新疆油田石油污染土壤中分离到一株在25 °C条件下利用烃类产生生物表面活性剂的菌株红球菌(Rhodococcus sp.) HL-6, 对其菌体细胞疏水性及所产表面活性剂进行研究。【方法】通过细胞粘附性、表面张力及乳化活性测定对菌株所产表面活性剂进行性质研究。【结果】菌株HL-6在亲水性和疏水性基质中均能产生生物表面活性剂, 在疏水性基质中可以将培养液表面张力由初始的62.487 mN/m降到30.667 mN/m, 培养液在pH 6?9及NaCl浓度1%?5%范围内乳化效果良好, 在4 °C到55 °C范围内乳化效果均为100%, 菌株对柴油的耐受能力很高, 在30%柴油浓度下依然生长良好并且有44%的乳化活性。【结论】HL-6菌株的细胞表面具有很强的疏水性, 这有助于菌体细胞对烃类的摄取。该菌株能够利用烃类基质生产生物表面活性剂, 可以明显降低培养液表面张力并且对石油烃具有良好的乳化作用。说明菌株HL-6能够适应海洋滩涂石油污染的环境, 并可用于严重石油污染区域的生物修复。     

Diversity of biosurfactant producing microorganisms isolated from soils contaminated with diesel oil

Biosurfactant production is a desirable property of hydrocarbon-degrading microorganisms (HDM). We characterized biosurfactant producing microbial populations from a Long Beach soil, California (USA) and a Hong Kong soil (China), contaminated with diesel oil. A total of 33 hydrocarbon-utilizing microorganisms were isolated from the soils. Twelve isolates and three defined consortia were tested for biosurfactant production and emulsification activity. The highest reduction of surface tension was achieved with a consortium of L1, L2 and L3 isolates from a Long Beach soil (41.4mN m(-1)). Isolate L1 (Acinetobacter junii) displayed the highest reduction of surface tension (46.5 mN m(-1)). The emulsifying capacity evaluated by the E24 emulsification index was highest in the culture of isolate L5 (74%). No substantial emulsification was achieved with the cell-free extracts, indicating that the emulsifying activity was not extracellular. Based on surface tension and the E24 index results, isolates F1, F2, F3, F4, L1, L2, L3 and L4 were identified by 16S rRNA gene sequencing as Bacillus cereus, Bacillus sphaericus, B. fusiformis, Acinetobacter junii, a non-cultured bacterium, Pseudomonas sp. and B. pumilus, respectively. Cluster analyses of 16S rRNA gene sequences of the bacterial isolates revealed 70% similarity amongst hydrocarbon-degrading bacterial community present in both soils. Five isolates (isolates F1, F2, F3, F4 and L4) belong to the Firmicutes order, two isolates (L1 and L3) belong to the Proteobacteria order and one isolate (L2) is an Actinomyces sp. Simpson's index (1 - D) and the Shannon-Weaver index (H) revealed more diversity of HDM in the Hong Kong soil, while evenness (E) and the equitability (J) data indicated that there was not a dominant population. Bacterial isolates displaying substantial potential for production of biosurfactants can be applied in the bioremediation of soils contaminated with petroleum hydrocarbons.     

Physicochemical and structural characterization of biosurfactant produced by <Emphasis Type="Italic">Pleurotus djamor</Emphasis> in solid-state fermentation

Biosurfactants are amphiphilic compounds produced by several microorganisms that reduce the surface tension. Low toxicity, optimal activity in extreme conditions, biodegradability and production from several wastes are main advantages of biosurfactants as compared to synthetic surfactants. Production of biosurfactant by a white rot fungus Pleurotus djamor on sunflower seed shell in solid-state fermentation was determined by emulsification indexes, oil spreading activity and surface tension (28.82 ± 0.3mN/m) measurement. The critical micelle concentration was detected as 0.964 ± 0.09 mg/mL. Also, the chemical and physicochemical properties of the biosurfactant produced were investigated. Considering the results of the chemical contents analysis, HPLC, FT-IR and ¹H-NMR, it can be concluded that the produced biosurfactant has a complex structure. Besides, resistance of its activity to environmental factors such as temperature, pH and salt concentration, as well as its thermal stability, were investigated. Additionally, the produced biosurfactant formed stabile emulsions with different hydrocarbons. Lastly, the performance of removing waste frying oil from contaminated sand of produced biosurfactant was detected as 76.57 ± 6%. Owing to its high emulsification capacity, low surface tension and critical micelle concentration, the biosurfactant, shows great potential for use in hydrocarbon removal applications.     

一株来自大西洋表层海水的烷烃降解菌Gordonia sp. S14-10的分离鉴定及其降解相关特性的分析

摘要：【目的】本研究的目的是从大西洋表层海水分离筛选新的烷烃降解菌,了解其降解基因及降解特性,为海洋石油污染的生物治理提供材料。【方法】以柴油与原油作为混合碳源从大西洋表层海水样品中富集、并分离筛选出降解能力较强的烷烃降解菌。根据16S rRNA基因和其看家基因secA1序列确定其系统进化地位。分析了烷烃降解范围、表面活性剂产生能力及其他生理生化特性;利用已报道的兼并引物进行了烷烃羟化酶基因的PCR扩增及系统进化分析。【结果】分离筛选得到1株能够降解C10?C36直链烷烃的菌株S14-10。经16S rR     

The Potential of Bacterial Isolates for Emulsification with a Range of Hydrocarbons

A study was undertaken to investigate the distribution of biosurfactant producing and crude oil degrading bacteria in the oil contaminated environment. This research revealed that hydrocarbon contaminated sites are the potent sources for oil degraders. Among 32 oil degrading bacteria isolated from ten different oil contaminated sites of gasoline and diesel fuel stations, 80% exhibited biosurfactant production. The quantity and emulsification activity of the biosurfactants varied. Pseudomonas sp. DS10‐129 produced a maximum of 7.5 ± 0.4 g/l of biosurfactant with a corresponding reduction in surface tension from 68 mN/m to 29.4 ± 0.7 mN/m at 84 h incubation. The isolates Micrococcus sp. GS2‐22, Bacillus sp. DS6‐86, Corynebacterium sp. GS5‐66, Flavobacterium sp. DS5‐73, Pseudomonas sp. DS10‐129, Pseudomonas sp. DS9‐119 and Acinetobacter sp. DS5‐74 emulsified xylene, benzene, n‐hexane, Bombay High crude oil, kerosene, gasoline, diesel fuel and olive oil. The first five of the above isolates had the highest emulsification activity and crude oil degradation ability and were selected for the preparation of a mixed bacterial consortium, which was also an efficient biosurfactant producing oil emulsifying and degrading culture. During this study, biosurfactant production and emulsification activity were detected in Moraxella sp., Flavobacterium sp. and in a mixed bacterial consortium, which have not been reported before.     

Protozoa in Subsurface Sediments from Sites Contaminated with Aviation Gasoline or Jet Fuel

Numbers of protozoa in the subsurface of aviation gasoline and jet fuel spill areas at a Coast Guard base at Traverse City, Mich., were determined. Boreholes were drilled in an uncontaminated location, in contaminated but untreated parts of the fuel plumes, and in the aviation gasoline source area undergoing H₂O₂ biotreatment. Samples were taken from the unsaturated zone to depths slightly below the floating free product in the saturated zone. Protozoa were found to occur in elevated numbers in the unsaturated zone, where fuel vapors mixed with atmospheric oxygen, and below the layer of floating fuel, where uncontaminated groundwater came into contact with fuel. The same trends were noted in the biotreatment area, except that numbers of protozoa were higher. Numbers of protozoa in some contaminated areas equalled or exceeded those found in surface soil. The abundance of protozoa in the biotreatment area was high enough that it would be expected to significantly reduce the bacterial community that was degrading the fuel. Little reduction in hydraulic conductivity was observed, and no bacterial fouling of the aquifer was observed during biotreatment.     

Potential for biodegradation of hydrocarbons in soil from the Ross Dependency, Antarctica

Oil spills occur in the Antarctic when fuel oils such as JP8 jet fuel are moved or stored. Hydrocarbons, both n-alkanes and aromatic compounds, have been detected in oil-contaminated soils of the Ross Dependency. In such areas hydrocarbon-degrading microbes, if naturally occurring, could be used for clean-up. Soil samples from oil-impacted and control sites were analysed for hydrocarbon-degrading microbes and for a range of parameters known to limit biodegradative activity. Soils were analysed for water content, pH, concentrations of nutrients (N and P) and electrical conductivity. Numbers of culturable heterotrophic bacteria and hydrocarbon degraders were greater in some of the oil-contaminated samples. Mineralisation studies with ¹⁴C-radiolabelled hexadecane and naphthalene demonstrated that nitrogen amendments significantly enhanced hydrocarbon mineralisation rates in an oil-impacted soil. Received: 30 June 1997 / Received revision: 15 September 1997 / Accepted: 19 September 1997     

Isolation and characterization of biosurfactant producing <Emphasis Type="Italic">Bacillus</Emphasis> sp. from diesel fuel-contaminated site

Among hydrocarbon pollutants, diesel oil is a complex mixture of alkanes and aromatic compounds which are often encountered as soil contaminants leaking from storage tanks and pipelines or as result of accidental spillage. One of the best ecofriendly approaches is to restore contaminated soil by using microorganisms able to degrade those toxic compounds in a bioremediation process. In the present study, nineteen bacteria were isolated by enrichment culture technique from diesel spilled soil collected from electric generator shed of NBAIM, Mau. All the isolates were subjected to screening for lipase production and twelve isolates were found to be positive for lipase. When the isolates were screened for biosurfactant production using CTAB-methylene blue agar plates, only one isolate viz. 2NBDSH3 was found positive which was found to be phylogenetically closely related with Bacillus flexus. Despite having low emulsification index, the bacterium could degrade 88.6% of diesel oil in soil. Biosurfactant from the isolate was extracted and characterized through infra-red spectroscopy which indicated its possible lipopeptide nature which was further supported by strong absorption in UV range in the UV-Vis spectrum. The results of the present study indicated that the isolate either does not produce any bioemulsifier or produces very low amount of emulsifier rather it produces a lipopeptide biosurfactant which helps in degradation of diesel oil by lowering the surface tension. The bacterium thus isolated and characterized can serve as a promising solution for ecofriendly remediation of bacterium diesel contaminated soils.     

Co-Utilization of Canola Oil and Glucose on the Production of a Surfactant by <Emphasis Type="Italic">Candida lipolytica</Emphasis>

Candida lipolytica synthesized a surfactant in a cultivation medium supplemented with canola oil and glucose as carbon sources. Measurements of biosurfactant production and surface tension indicated that the biosurfactant was produced at 48 h of fermentation. The surface-active species is constituted by the protein–lipid–polysaccharide complex in nature. The cell-free broth was particularly influenced by the addition of salt, the pH and temperature depending on the emulsified substrate (hexadecane or a vegetable oil). After comparison between ethyl acetate and mixtures of chloroform and methanol as solvent systems for surfactant recovery, it was found that ethyl acetate was able to extract crude surfactant material with high product recovery (8.0 g/L). The isolated biosurfactant decreased the surface tension to values of 30 mN/m at the critical micelle concentration. Emulsification properties of the biosurfactant produced were compared to those of commercial emulsifiers and other microbial surfactants.     

Potential use of endophytic root bacteria and host plants to degrade hydrocarbons

Abstract

Microbe-assisted phytoremediation depends on competent root-associated microorganisms that enhance remediation efficiency of organic compounds. Endophytic bacteria are a key element of the root microbiome and may assist plant degradation of contaminants. The aim of this study was to investigate the application of four hydrocarbon-degrading endophytic strains previously isolated from an oil sands reclamation area. Strains EA1-17 (Stenotrophomonas sp.), EA2-30 (Flavobacterium sp.), EA4-40 (Pantoea sp.), and EA6-5 (Pseudomonas sp.) were inoculated in white sweet clover growing on soils amended with diesel at 5,000, 10,000, and 20,000?mg·kg^?1. Our results indicate that plant growth inhibition caused by diesel fuel toxicity was overcome in inoculated plants, which showed significantly higher plant biomass. Analysis of soil F2 and F3 hydrocarbon fractions also revealed that these soils were remediated by inoculated plants when diesel was applied at 10,000?mg·kg^?1 and 20,000?mg·kg^?1. In addition, quantification of hydrocarbon-degrading genes suggests that all bacterial strains successfully colonized sweet clover plants. Overall, the endophytic strain EA6-5 (Pseudomonas sp.), which harbored hydrocarbon-degrading genes, was the most effective candidate in phytoremediation experiments and could be a strategy to increase plant tolerance and hydrocarbon degradation in contaminated (e.g., diesel fuel) soils.     

In Situ Rhamnolipid Production at an Abandoned Petroleum Refinery

A simple screening method was developed to detect in situ biosurfactant production by exploiting the relationship between surface tension (ST) and surfactant concentration. Filtered groundwater from contaminated wells with ST values of 60 to 70 dynes/cm decreased to 29 dynes/cm after being concentrated 10 to 15 times in a rotary evaporator, indicating that biosurfactants in the sample reached the critical micelle concentration (CMC). Samples from uncon-taminated groundwater concentrated 25 times showed no decrease in ST below 72 dynes/cm, suggesting that biosurfactants were not present. Microorganisms from soil cores were cultured on diesel fuel and identified using fatty acid methyl ester (FAME) analysis. Pseudomonas aeruginosa was found at very low numbers in uncontami-nated soil but was the dominant species in contaminated soil, indicating that hydrocarbon release impacted microbial diversity significantly. High-performance liquid chromatography (HPLC) was used to quantify rhamnolipids, biosurfactants produced by P. aeruginosa, in concentrated ground-water samples. Rhamnolipid concentrations in samples from contaminated soil were observed equal to their CMC (50 mg/L), but were not detected in samples from un-contaminated wells. We conclude that biosurfactant production may be an indicator of intrinsic bioremediation.     

Identification of nitrogen-incorporating bacteria in petroleum-contaminated arctic soils by using [15N]DNA-based stable isotope probing and pyrosequencing

Arctic soils are increasingly susceptible to petroleum hydrocarbon contamination, as exploration and exploitation of the Arctic increase. Bioremediation in these soils is challenging due to logistical constraints and because soil temperatures only rise above 0°C for ∼2 months each year. Nitrogen is often added to contaminated soil in situ to stimulate the existing microbial community, but little is known about how the added nutrients are used by these microorganisms. Microbes vary widely in their ability to metabolize petroleum hydrocarbons, so the question becomes: which hydrocarbon-degrading microorganisms most effectively use this added nitrogen for growth? Using [¹⁵N]DNA-based stable isotope probing, we determined which taxonomic groups most readily incorporated nitrogen from the monoammonium phosphate added to contaminated and uncontaminated soil in Canadian Forces Station-Alert, Nunavut, Canada. Fractions from each sample were amplified with bacterial 16S rRNA and alkane monooxygenase B (alkB) gene-specific primers and then sequenced using lage-scale parallel-pyrosequencing. Sequence data was combined with 16S rRNA and alkB gene C quantitative PCR data to measure the presence of various phylogenetic groups in fractions at different buoyant densities. Several families of Proteobacteria and Actinobacteria that are directly involved in petroleum degradation incorporated the added nitrogen in contaminated soils, but it was the DNA of Sphingomonadaceae that was most enriched in ¹⁵N. Bacterial growth in uncontaminated soils was not stimulated by nutrient amendment. Our results suggest that nitrogen uptake efficiency differs between bacterial groups in contaminated soils. A better understanding of how groups of hydrocarbon-degraders contribute to the catabolism of petroleum will facilitate the design of more targeted bioremediation treatments.     

Characterization and properties of biosurfactants produced by a newly isolated strain <Emphasis Type="Italic">Bacillus methylotrophicus</Emphasis> DCS1 and their applications in enhancing solubility of hydrocarbon

Six biosurfactant-producing bacteria were isolated from hydrocarbon contaminated soils in Sfax, Tunisia. Isolates were screened for biosurfactant production by different conventional methods including hemolytic activity, surface tension reduction, drop-collapsing and oil displacement tests. All these screening tests show that all the isolates behave differently. Among the isolated bacteria, DCS1 strain was selected for further studies based on its highest activities and it was identified as Bacillus methylotrophicus DCS1. This strain was found to be a potent producer of biosurfactant when cultivated in mineral-salts medium supplemented with diesel oil (2 %, v/v) as a sole carbon source. Physicochemical properties and stability of biosurfactants synthesized by B. methylotrophicus DCS1 were investigated. The produced biosurfactants DCS1, from Landy medium, possess high surface activity that could lower the surface tension of water to a value of 31 from 72 mN m^?1 and have a critical micelle concentration (CMC) of 100 mg L^?1. Compared with SDS and Tween 80, biosurfactants showed excellent emulsification activities against different hydrocarbon substrates and high solubilization efficiency towards diesel oil. Biosurfactants DCS1 showed good stability in a wide range of temperature, pH and salinity. These results suggested that biosurfactants produced by B. methylotrophicus DCS1 could be an alternative to chemically synthesized surfactants for use in bioremediation processes to enhance the solubility of hydrophobic compounds.     

Aromatic hydrocarbon-degrading bacteria from soil near Scott Base, Antarctica

Hydrocarbons persist in Antarctic soils when fuel oils such as JP8 jet fuel are spilled. For clean-up of hydrocarbon-contaminated soils in Antarctica, bioremediation has been proposed using hydrocarbon-degrading microbes indigenous to Antarctic soils. A number of alkane-degrading bacteria have been isolated previously from Antarctic soils. In this paper we describe the direct isolation of aromatic hydrocarbon-degrading bacteria from oil-contaminated Antarctic soil. Isolates that grew on JP8 jet fuel were characterised for their ability to degrade aromatic and aliphatic hydrocarbons and for growth at a range of temperatures. All isolates were gram-negative, oxidase-positive, rod-shaped bacteria. Representative strains were identified using 16S rDNA sequence analysis as either Sphingomonas spp. or Pseudomonas spp. Aromatic-degrading bacteria from Antarctic soils were psychrotolerant and appear similar to those found worldwide. Accepted: 27 September 1999     

A Comparative Study on Biosurfactant Activity of Crude Oil–Degrading Bacteria and Its Correlation to Total Petroleum Hydrocarbon Degradation

In this study, 11 bacteria isolated from Tapis crude oil–contaminated sites were identified by using biochemical tests and 16S rDNA gene sequencing. Their abilities to biodegrade Tapis crude oil was determined by gas chromatography before they were further screened for biosurfactant activity by employing qualitative (blood agar hemolysis, microplate assay, drop-collapse test), semiquantitative (emulsification formation), and quantitative (surface tension measurement) methods. Four isolates, namely, Acinetobacter baumanii UKMP-12T, Pseudomonas aeruginosa UKMP-14T, Rhodococcus sp. UKMP-5T, and Rhodococcus sp. UKMP-7T, exhibited high percentages in total petroleum hydrocarbon (TPH) degradation. A strong correlation between the emulsification index (E ₂₄) and surface tension measurement (r _s = +.866) as shown by Spearman rank correlation analysis suggested that these two methods were more reliable to predict biosurfactant activity. The TPH removal was also positively correlated to the ability of bacterial isolates to reduce the surface tension of growth medium, as revealed by Pearson correlation test (r_p = +.886). In conclusion, not all the biosurfactant detection protocols employed were effective. Nevertheless, the measurement of surface tension and E ₂₄ determination provided a rather rapid, easy, reproducible, and accurate result in identifying bacteria with biosurfactant-producing ability.     

Biosurfactant-Mediated Biodegradation of Polycyclic Aromatic Hydrocarbons—Naphthalene

The present study is aimed at the naphthalene degradation with and without biosurfactant produced from Pseudomonas aeruginosa isolated from oil-contaminated soil. The present study was carried out to isolate the bacterial strains for the naphthalene degradation and also for biosurfactant production. The isolated strains were screened for their ability to degrade the naphthalene by the methods of optimum growth rate test and for the production of biosurfactants by cetyltrimethylammonium bromide, blood agar medium, and thin-layer chromatography. The present study also focused on the effect of biosurfactant for the degradation of naphthalene by isolate-1. Two bacterial strains were isolated and screened, one for biodegradation and another for biosurfactant production. The second organism was identified as Pseudomonas aeruginosa by 16S rRNA analysis. The purified biosurfactant reduces the surface tension of water and also forms stable emulsification with hexadecane and kerosene. The end product of naphthalene degradation was estimated as salicylic acid equivalent by spectrophotometric method. The results demonstrated that Pseudomonas aeruginosa has the potential to produce biosurfactant, which enhances the biodegradation of naphthalene. The study reflects the potential use of biosurfactants for an effective bioremediation in the management of contaminated soils.     

Crude biosurfactant from thermophilic Alcaligenes faecalis: Feasibility in petro-spill bioremediation

The thermophilic bacterium Alcaligenes faecalis isolated from the crude oil contaminated soil of Upper Assam, India. The isolated bacterium was first screened for the ability to produce biosurfactant. The strain growing at 42 °C could produce higher amount of biosurfactant in medium supplemented with 2% (v/v) diesel as sole source of carbon and energy. Biochemical characterizations including FT-IR and MS studies suggested the biosurfactant to be glycolipid. Tensiometric studies revealed that the biosurfactant produced by the bacterial strain could decrease the surface tension (??) at air-water interface from 71.6 to 32.3 mNm⁻¹ after 96 h of growth on hydrocarbon and possessed a low critical micelle concentration (CMC) value of approximately 38 mgl⁻¹, indicating high surface activity. The culture supernatant containing the biosurfactant was found to be functionally stable at varying pH (2-12), temperature (100 and 121 °C) and salinity (1-6% NaCl, w/v) conditions. Both the culture broth and the cell free supernatant exhibited high emulsifying activity against the different hydrocarbons and the crude oil components. The increase in cell surface hydrophobicity and glycolipid production by the strain suggested the existence of biosurfactant enhanced interfacial uptake of the hydrocarbons. Moreover, the partially purified biosurfactant exhibited antimicrobial activity by inhibiting the growth of several bacterial and fungal species. The strain represented a new class of biosurfactant producers and could be a potential candidate for the production of glycolipid biosurfactant which could be useful in a variety of biotechnological and industrial processes, particularly in the oil industry.     

Enhanced biodegradation and emulsification of crude oil and hyperproduction of biosurfactants by a gamma ray-induced mutant of Pseudomonas aeruginosa

A gamma ray-induced mutant of Pseudomonas aeruginosa strain S8, capable of hyperproduction of biosurfactant from hydrocarbons, was isolated and named as EBN-8. The mutant showed 3–4 times more hydrocarbon emulsification/conversion as compared to the parent when grown on Khaskheli crude oil in minimal medium. Enhanced biosurfactant production and hydrocarbon utilization by the mutant was also observed during growth on heptadecane in minimal medium as indicated by emulsion index and surface tension of cell-free culture broth. Using heptadecane as carbon and energy source, time course for the growth (cfu ml^-1) and biosurfactant production were compared for both parent and mutant. These studies were carried out for 24 d at 30 ± 2°C and for 20 d at 37°C. Growth of EBN-8 was much faster compared to the parent as well as being 2–3 times more hyperproductive.     

Microbial Degradation of Organic Pollutants in Soil in a Cold Climate

Cold-adapted microorganisms are potentially interesting for use in environmental biotechnology applications since a large part of the biosphere has low temperatures during at least parts of the year. Many studies have shown that both oil-contaminated and uncontaminated soils in the Arctic, the Antarctic and the Alps contain microbes that can degrade different hydrocarbons deriving from oils. A few studies have also been conducted on degradation of herbicides in soils at low temperatures. Furthermore, phenols and some polychlorinated biphenyl (PCB) congeners have proved to be degradable at low temperatures, using microorganisms isolated from sediments or soils. Additions of nitrogen and phosphorous to polluted soils have been shown to enhance the degradation of hydrocarbons in many cases. Bioaugmentation with hydrocarbon degrading cold-adapted microorganisms has given varying results. The inoculated microorganisms have probably been out-competed by the indigenous microorganisms in some cases. Different ways to increase the efficiency of microbial degradation of organic pollutants in soil in a cold climate is discussed.     

Bioprospection and selection of bacteria isolated from environments contaminated with petrochemical residues for application in bioremediation

The use of microorganisms with hydrocarbon degrading capability and biosurfactant producers have emerged as an alternative for sustainable treatment of environmental passives. In this study 45 bacteria were isolated from samples contaminated with petrochemical residues, from which 21 were obtained from Landfarming soil contaminated with oily sludge, 11 were obtained from petrochemical industry effluents and 13 were originated directly from oily sludge. The metabolization capability of different carbon sources, growth capacity and tolerance, biosurfactant production and enzymes detection were determined. A preliminary selection carried out through the analysis of capability for degrading hydrocarbons showed that 22% of the isolates were able to degrade all carbon sources employed. On the other hand, in 36% of the isolates, the degradation of the oily sludge started within 18–48 h. Those isolates were considered as the most efficient ones. Twenty isolates, identified based on partial sequencing of the 16S rRNA gene, were pre-selected. These isolates showed ability for growing in a medium containing 1% of oily sludge as the sole carbon source, tolerance in a medium containing up to 30% of oily sludge, ability for biosurfactant production, and expression of enzymes involved in degradation of aliphatic and aromatic compounds. Five bacteria, identified as Stenotrophomonas acidaminiphila BB5, Bacillus megaterium BB6, Bacillus cibi, Pseudomonas aeruginosa, and Bacillus cereus BS20 were shown to be promising for use as inoculum in bioremediation processes (bioaugmentation) of areas contaminated with petrochemical residues since they can use oily sludge as the sole carbon source and produce biosurfactants.