Endophytic bacteria of garlic roots promote growth of micropropagated meristems.

Garlic (Allium sativum L.) is one of the crops whose economic importance has increased considerably in recent years in Brazil. The use of plant growth-promoting bacteria (PGPB) is a useful alternative for reducing the cost of agricultural inputs and, consequently, for increasing productivity. Therefore, the main objective of this work was to isolate and evaluate potential growth promoters in plants and plant pathogenic fungi growth inhibitors using endophytic bacteria from garlic roots and bacteria from the Agricultural Microbiology Culture Collection at the Federal University of Lavras. Besides verifying improvements in the growth and physiology of garlic meristems grown in vitro under the action of PGPB. Forty-eight endophytic bacteria were identified using matrix-assisted laser desorption/ionization-time of flight mass spectrometry based on the protein profile of each isolate. Four isolates were chosen according to their ability to fix nitrogen, to produce auxin and solubilize phosphate. The cultivation of garlic meristems in tissue culture with these bacteria was established at a population level of 106 CFU/mL. The evaluated criteria were: (1) the colonization capacity of the bacteria inside the garlic plants determined through scanning electron microscopy; (2) the chlorophyll content; and (3) the growth of garlic plants in vitro post-PGPB inoculation. Volatiles emitted by those isolates inhibited fungi growth. The inoculation of garlic meristems with Enterobacter cloacae and Burkholderia cepacia promoted an improvement in the growth and physiological attributes of garlic, indicating the feasibility of their application as plant growth promoters for commercial cultivation.

Cefpirome Treatment Results in Limited Selection of Stable Derepressed Enterobacter cloacae Mutants in the Intestinal Flora of Rats Treated for an Experimental Klebsiella pneumoniae Pulmonary Infection.

Background: Fourth-generation cephalosporins have been developed to improve their potency, that is, low minimal inhibitory concentrations (MICs) and to prevent resistance selection of derepressed AmpC-producing mutants in comparison to third-generation cephalosporins as ceftazidime. Objectives: We investigated the role of the administered cefpirome dose on the efficacy of treatment of a Klebsiella pneumoniae lung infection as well as in the selection of resistant Enterobacter cloacae isolates in the intestines of rats treated for a K. pneumoniae lung infection. Materials and Methods: Rats with K. pneumoniae lung infection received therapy with cefpirome doses of 0.4 to 50 mg/kg/day b.i.d. for 18 days. Resistance selection in intestinal E. cloacae was monitored during 43 days. Mutants were checked for ß-lactamase activity, mutations in their structural ampC gene, ampD gene, and omp39-40 gene. Results: A 45% and 100% rat survival rate was obtained by administration of 3.1 and 12.5 mg/kg b.i.d. of cefpirome. A significant correlation was demonstrated in the reduction of the susceptible E. cloacae isolates with %fT>MIC at days 7, 14, 22, and 29. Cefpirome E. cloacae mutants, with increased cefpirome MICs, were obtained in only four rats. Conclusions: The treatment with cefpirome resulted in less selection of derepressed mutants in comparison to ceftazidime as shown by their low number per gram of feces and in a limited number of animals.

Long-Term Impact of Suppressive Antibiotic Therapy on Intestinal Microbiota.

The aim was to describe the safety of indefinite administration of antibiotics, the so-called suppressive antibiotic therapy (SAT) and to provide insight into their impact on gut microbiota. 17 patients with SAT were recruited, providing a fecal sample. Bacterial composition was determined by 16S rDNA massive sequencing, and their viability was explored by PCR-DGGE with and without propidium monoazide. Presence of antibiotic multirresistant bacteria was explored through the culture of feces in selective media. High intra-individual variability in the genera distribution regardless of the antibiotic or antibiotic administration ingestion period, with few statistically significant differences detected by Bray-Curtis distance-based principle component analysis, permutational multivariate analysis of variance and linear discriminant analysis effect size analysis. However, the microbiota composition of patients treated with both beta-lactams and sulfonamides clustered by a heat map. Curiously, the detection of antibiotic resistant bacteria was almost anecdotic and CTX-M-15-producing E. coli were detected in two subjects. Our work demonstrates the overall clinical safety of SAT and the low rate of the selection of multidrug-resistant bacteria triggered by this therapy. We also describe the composition of intestinal microbiota under the indefinite use of antibiotics for the first time.

New insights into the chemical profiling, cytotoxicity and bioactivity of four Bunium species.

Bunium species have been reported to be used both as food and in traditional medicines. The scientific community has attempted to probe into the pharmacological and chemical profiles of this genus. Nonetheless, many species have not been investigated fully to date. In this study, we determined the phenolic components, antimicrobial, antioxidant, and enzyme inhibitory activities of aerial parts of four Bunium species (B. sayai, B. pinnatifolium, B. brachyactis and B. macrocarpum). Results showed that B. microcarpum and B. pinnatifolium were strong antioxidants as evidenced in the DPPH, ABTS, CUPRAC, and FRAP assays. B. brachyactis was the most effective metal chelator, and displayed high enzyme inhibition against cholinesterase, tyrosinase, amylase, glucosidase, and lipase. The four species showed varied antimicrobial activity against each microorganism. Overall, they showed high activity against P. mirabilis and E. coli (MIC and MBC <1 mg mL-1). B. brachyactis was more effective against Aspergillus versicolor compared to the standard drug ketoconazole. B. brachyactis was also more effective than both ketoconazole and bifonazole against Trichoderma viride. B. sayai was more effective than ketoconazole in inhibiting A. fumigatus. B. sayai was most non-toxic to HEK 293 (cellular viability = 117%) and HepG2 (cellular viability = 104%). The highest level of TPC was observed in B. pinnatifolium (35.94 mg GAE g-1) while B. microcarpum possessed the highest TFC (39.21 mg RE g-1). Seventy four compounds were detected in B. microcarpum, 70 in B. brachyactis, 66 in B. sayai, and 51 in B. pinnatifolium. Quinic acid, chlorogenic acid, pantothenic acid, esculin, isoquercitrin, rutin, apigenin, and scopoletin were present in all the four species. This study showed that the four Bunium species are good sources of biologically active compounds with pharmaceutical and nutraceutical potential.

Inhibition of Fosfomycin Resistance Protein FosA by Phosphonoformate (Foscarnet) in Multidrug-Resistant Gram-Negative Pathogens.

FosA proteins confer fosfomycin resistance to Gram-negative pathogens via glutathione-mediated modification of the antibiotic. In this study, we assessed whether inhibition of FosA by sodium phosphonoformate (PPF) (foscarnet), a clinically approved antiviral agent, would reverse fosfomycin resistance in representative Gram-negative pathogens. The inhibitory activity of PPF against purified recombinant FosA from Escherichia coli (FosA3), Klebsiella pneumoniae (FosAKP), Enterobacter cloacae (FosAEC), and Pseudomonas aeruginosa (FosAPA) was determined by steady-state kinetic measurements. The antibacterial activity of PPF against FosA in clinical strains of these species was evaluated by susceptibility testing and time-kill assays. PPF increased the Michaelis constant (Km ) for fosfomycin in a dose-dependent manner, without affecting the maximum rate (Vmax) of the reaction, for all four FosA enzymes tested, indicating a competitive mechanism of inhibition. Inhibitory constant (Ki ) values were 22.6, 35.8, 24.4, and 56.3 µM for FosAKP, FosAEC, FosAPA, and FosA3, respectively. Addition of clinically achievable concentrations of PPF (∼667 µM) reduced the fosfomycin MICs by ≥4-fold among 52% of the K. pneumoniae, E. cloacae, and P. aeruginosa clinical strains tested and led to a bacteriostatic or bactericidal effect in time-kill assays among representative strains. PPF inhibits FosA activity across Gram-negative species and can potentiate fosfomycin activity against the majority of strains with chromosomally encoded fosA These data suggest that PPF may be repurposed as an adjuvant for fosfomycin to treat infections caused by some FosA-producing, multidrug-resistant, Gram-negative pathogens.

The effect of dietary bacterial organic selenium on growth performance, antioxidant capacity, and Selenoproteins gene expression in broiler chickens.

BACKGROUND: Selenium (Se) is an essential trace mineral in broilers, which has several important roles in biological processes. Organic forms of Se are more efficient than inorganic forms and can be produced biologically via Se microbial reduction. Hence, the possibility of using Se-enriched bacteria as feed supplement may provide an interesting source of organic Se, and benefit broiler antioxidant system and other biological processes. The objective of this study was to examine the impacts of inorganic Se and different bacterial organic Se sources on the performance, serum and tissues Se status, antioxidant capacity, and liver mRNA expression of selenoproteins in broilers. RESULTS: Results indicated that different Se sources did not significantly (P ≤ 0.05) affect broiler growth performance. However, bacterial organic Se of T5 (basal diet +0.3 mg /kg feed ADS18 Se), T4 (basal diet +0.3 mg /kg feed ADS2 Se), and T3 (basal diet +0.3 mg /kg feed ADS1 Se) exhibited significantly (P ≤ 0.05) highest Se concentration in serum, liver, and kidney respectively. Dietary inorganic Se and bacterial organic Se were observed to significantly affect broiler serum ALT, AST, LDH activities and serum creatinine level. ADS18 supplemented Se of (Stenotrophomonas maltophilia) bacterial strain showed the highest GSH-Px activity with the lowest MDA content in serum, and the highest GSH-Px and catalase activity in the kidney, while bacterial Se of ADS2 (Klebsiella pneumoniae) resulted in a higher level of GSH-Px1 and catalase in liver. Moreover, our study showed that in comparison with sodium selenite, only ADS18 bacterial Se showed a significantly higher mRNA level in GSH-Px1, GSH-Px4, DIO1, and TXNDR1, while both ADS18 and ADS2 showed high level of mRNA of DIO2 compared to sodium selenite. CONCLUSIONS: The supplementation of bacterial organic Se in broiler chicken, improved tissue Se deposition, antioxidant status, and selenoproteins gene expression, and can be considered as an effective alternative source of Se in broiler chickens.

Aerobic biogenesis of selenium nanoparticles by Enterobacter cloacae Z0206 as a consequence of fumarate reductase mediated selenite reduction.

In the present study, we examined the ability of Enterobacter cloacae Z0206 to reduce toxic sodium selenite and mechanism of this process. E. cloacae Z0206 was found to completely reduce up to 10 mM selenite to elemental selenium (Se°) and form selenium nanoparticles (SeNPs) under aerobic conditions. The selenite reducing effector of E. cloacae Z0206 cell was to be a membrane-localized enzyme. iTRAQ proteomic analysis revealed that selenite induced a significant increase in the expression of fumarate reductase. Furthermore, the addition of fumarate to the broth and knockout of fumarate reductase (frd) both significantly decreased the selenite reduction rate, which revealed a previously unrecognized role of E. cloacae Z0206 fumarate reductase in selenite reduction. In contrast, glutathione-mediated Painter-type reactions were not the main pathway of selenite reducing. In conclusion, E. cloacae Z0206 effectively reduced selenite to Se° using fumarate reductase and formed SeNPs; this capability may be employed to develop a bioreactor for treating Se pollution and for the biosynthesis of SeNPs in the future.

Optimization of Enterobacter cloacae (KU923381) for diesel oil degradation using response surface methodology (RSM).

Efficiency of Enterobacter cloacae KU923381 isolated from petroleum hydrocarbon contaminated soil was evaluated in batch culture and bioreactor mode. The isolate were screened for biofilm formation using qualitative and quantitative assays. Response surface methodology (RSM) was used to study the effect of pH, temperature, glucose concentration, and sodium chloride on diesel degradation. The predicted values for diesel oil degradation efficiency by the statistical designs are in a close agreement with experimental data (R 2 = 99.66%). Degradation efficiency is increased by 36.78% at pH = 7, temperature = 35°C, glucose = 5%, and sodium chloride concentration = 5%. Under the optimized conditions, the experiments were performed for diesel oil degradation by gas chromatographic mass spectrometric analysis (GC-MS). GC-MS analysis confirmed that E. cloacae had highly degrade hexadecane, heptadecane, tridecane, and docosane by 99.71%, 99.23%, 99.66%, and 98.34% respectively. This study shows that rapid bioremoval of hydrocarbons in diesel oil is acheived by E. cloacae with abet of biofilm formation. The potential use of the biofilms for preparing trickling filters (gravel particles) for the degradation of hydrocarbons from petroleum wastes before their disposal in the open environment is highly suggested. This is the first successful attempt for artificially establishing petroleum hydrocarbon degrading bacterial biofilm on solid substrates in bioreactor.

Cross-Linked Polymer-Stabilized Nanocomposites for the Treatment of Bacterial Biofilms.

Infections caused by bacterial biofilms are an emerging threat to human health. Conventional antibiotic therapies are ineffective against biofilms due to poor penetration of the extracellular polymeric substance secreted by colonized bacteria coupled with the rapidly growing number of antibiotic-resistant strains. Essential oils are promising natural antimicrobial agents; however, poor solubility in biological conditions limits their applications against bacteria in both dispersed (planktonic) and biofilm settings. We report here an oil-in-water cross-linked polymeric nanocomposite (∼250 nm) incorporating carvacrol oil that penetrates and eradicates multidrug-resistant (MDR) biofilms. The therapeutic potential of these materials against challenging wound biofilm infections was demonstrated through specific killing of bacteria in a mammalian cell-biofilm coculture wound model.

Cefepime Therapy for Monomicrobial Enterobacter cloacae Bacteremia: Unfavorable Outcomes in Patients Infected by Cefepime-Susceptible Dose-Dependent Isolates.

A new category of cefepime susceptibility, susceptible dose dependent (SDD), for Enterobacteriaceae, has been suggested to maximize its clinical use. However, clinical evidence supporting such a therapeutic strategy is limited. A retrospective study of 305 adults with monomicrobial Enterobacter cloacae bacteremia at a medical center from 2008 to 2012 was conducted. The patients definitively treated with in vitro active cefepime (cases) were compared with those treated with a carbapenem (controls) to assess therapeutic effectiveness. The 30-day crude mortality rate is the primary endpoint, and clinical prognostic factors are assessed. Of 144 patients receiving definitive cefepime or carbapenem therapy, there were no significant differences in terms of age, sex, comorbidity, source of bacteremia, disease severity, or 30-day mortality (26.4% versus 22.2%; P = 0.7) among those treated with cefepime (n = 72) or a carbapenem (n = 72). In the multivariate analysis, the presence of critical illness, rapidly fatal underlying disease, extended-spectrum beta-lactamase (ESBL) producers, and cefepime-SDD (cefepime MIC, 4 to 8 µg/ml) isolates was independently associated with 30-day mortality. Moreover, those infected by cefepime-SDD isolates with definitive cefepime therapy had a higher mortality rate than those treated with a carbapenem (5/7 [71.4%], versus 2/11 [18.2%]; P = 0.045). Cefepime is one of the therapeutic alternatives for cefepime-susceptible E. cloacae bacteremia but is inefficient for cases of cefepime-SDD E. cloacae bacteremia compared with carbapenem therapy.

Comparative evaluation of fermentative hydrogen production using Enterobacter cloacae and mixed culture: effect of Pd (II) ion and phytogenic palladium nanoparticles.

Palladium nanoparticles (PdNPs) were synthesized from PdCl2 using Coriandrum sativum leaf extract. The transmission electron microscopy (TEM) images confirm that the formation of PdNPs was mainly spherical in shape, with an average size of 87 nm. The influence of the PdCl2 and synthesized PdNPs on fermentative hydrogen production from glucose using Enterobacter cloacae and mixed culture was evaluated. In PdCl2 supplemented experiments, the hydrogen yields of E. cloacae and mixed culture were 1.39 ± 0.07 and 2.11 ± 0.11 mol H2/mol glucose, respectively, with 5.0 mg/L of PdCl2. The resulting hydrogen yield (P < 0.05) was lower than that of the control experiment (without supplementation), due to the soluble metabolites shift. However, the highest hydrogen yields of E. cloacae and mixed culture were 1.48 ± 0.04 and 2.48 ± 0.09 mol H2/mol glucose, respectively at 5.0 mg/L of PdNPs supplementation. The enhancement of biohydrogen production using mixed culture was significantly higher than that of E. cloacae as the same concentration of PdNPs.

Selenium-enriched exopolysaccharides improve skeletal muscle glucose uptake of diabetic KKAy mice via AMPK pathway

Selenium-enriched exopolysaccharides (EPS) produced by Enterobacter cloacae Z0206 have been proven to possess effect on reducing blood glucose level in diabetic mice. To investigate the specific mechanism, we studied the effects of oral supply with EPS on skeletal muscle glucose transportation and consumption in high-fat-diet-induced diabetic KKAy mice. We found that EPS supplementation increased expressions of glucose transporter 4 (Glut4), hexokinase 2 (hk2), phosphorylation of AMP-activated kinase subunit α2 (pAMPKα2), and peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), and increased expression of characteristic protein of oxidative fibers such as troponin I and cytochrome c (Cytc). Furthermore, we found that EPS increased glucose uptake and expressions of pAMPKα2 and PGC-1α in palmitic acid (PA)-induced C2C12 cells. However, while EPS inhibited AMPKα2 with interference RNA (iRNA), effects of EPS on the improvement of glucose uptake diminished. These results indicated that EPS may improve skeletal muscle glucose uptake of diabetic KKAy mice through AMPKα2-PGC-1α pathway

Study of bio-degradation and bio-decolourization of azo dye by Enterobacter sp. SXCR.

The objective of this study was to evaluate the decolourization potential of textile dyes by a relatively newly identified bacteria species, Enterobacter sp. SXCR which was isolated from the petroleum polluted soil samples. The bacterial strain was identified by 16S rRNA gene sequence analysis. The effects of operational conditions like initial dye concentration, pH, and temperature were optimized to develop an economically feasible decolourization process. The isolate was able to decolourize sulphonated azo dye (Congo red) over a wide range (0.1-1 gl(-1)), pH 5-9, and temperature 22-40 degrees C in static condition. Anaerobic condition with minimal salt medium supplemented with 2 gl(-1) glucose, pH 7 and 34 degrees C were considered to be the optimum decolourizing condition. The bacterial isolate SXCR showed a strong ability to decolourize dye (0.2 gl(-1)) within 93 h. The biodegradation was monitored by UV-vis, fourier transform infra-red spectroscopy (FTIR) spectroscopy and high performance liquid chromatography (HPLC). Furthermore, the involvement of azoreductase in the decolourization process was identified in this strain. Cells of Enterobacter cloacae were immobilized by entrapment in calcium-alginate beads. Immobilized bacterial cells were able to reduced azo bonds enzymatically and used as a biocatalyst for decolourization of azo dye Congo red. Michaelis-Menten kinetics was used to describe the correlation between the decolourization rate and the dye concentration.

Isolation and characterization of a glyphosate-degrading rhizosphere strain, Enterobacter cloacae K7.

Plant-growth-promoting rhizobacteria exert beneficial effects on plants through their capacity for nitrogen fixation, phytohormone production, phosphate solubilization, and improvement of the water and mineral status of plants. We suggested that these bacteria may also have the potential to express degradative activity toward glyphosate, a commonly used organophosphorus herbicide. In this study, 10 strains resistant to a 10 mM concentration of glyphosate were isolated from the rhizoplane of various plants. Five of these strains--Alcaligenes sp. K1, Comamonas sp. K4, Azomonas sp. K5, Pseudomonas sp. K3, and Enterobacter cloacae K7--possessed a number of associative traits, including fixation of atmospheric nitrogen, solubilization of phosphates, and synthesis of the phytohormone indole-3-acetic acid. One strain, E. cloacae K7, could utilize glyphosate as a source of P. Gas-liquid chromatography showed that E. cloacae growth correlated with a decline in herbicide content in the culture medium (40% of the initial 5mM content), with no glyphosate accumulating inside the cells. Thin-layer chromatography analysis of the intermediate metabolites of glyphosate degradation found that E. cloacae K7 had a C-P lyase activity and degraded glyphosate to give sarcosine, which was then oxidized to glycine. In addition, strain K7 colonized the roots of common sunflower (Helianthus annuus L.) and sugar sorghum (Sorghum saccharatum Pers.), promoting the growth and development of sunflower seedlings. Our findings extend current knowledge of glyphosate-degrading rhizosphere bacteria and may be useful for developing a biotechnology for the cleanup and restoration of glyphosate-polluted soils.

Highly regioselective glycosylation of xylosyl-containing taxanes by Enterobacter cloaceae.

Three new diglycoside taxanes (4-6) containing an additional α-d-glucose unit were obtained via Enterobacter cloaceae-mediated, highly regioselective glycosylations at OH-4 of the xylosyl moieties in 7-xylosyl taxanes (1-3). Their structures were determined on the basis of extensive spectroscopic analysis and chemical reactivity. This is the first report of an enzymatic elongation of the saccharide chain in taxanes, and the glycosylation reaction is the first described example of a transformation effected by E. cloaceae.

Efficient 2,3-butanediol production from cassava powder by a crop-biomass-utilizer, Enterobacter cloacae subsp. dissolvens SDM.

BACKGROUND: 2,3-Butanediol (BD) is considered as one of the key platform chemicals used in a variety of industrial applications. It is crucial to find an efficient sugar-utilizing strain and feasible carbon source for the economical production of BD. METHODOLOGY/PRINCIPAL FINDINGS: Efficient BD production by a newly isolated Enterobacter cloacae subsp. dissolvens SDM was studied using crop-biomass cassava powder as substrate. The culture conditions and fermentation medium for BD production were optimized. Under the optimal conditions, 78.3 g l(-1) of BD was produced after 24 h in simultaneous saccharification and fermentation (SSF), with a yield of 0.42 g BD g(-1) cassava powder and a specific productivity of 3.3 g l(-1) h(-1). A higher BD concentration (93.9 g l(-1)) was produced after 47 h in fed-batch SSF. CONCLUSIONS/SIGNIFICANCE: The results suggest that strain SDM is a good candidate for the BD production, and cassava powder could be used as an alternative substrate for the efficient production of BD.

Effects of organic nutrients and growth factors on biostimulation of tributyltin removal by sediment microorganisms and Enterobacter cloacae.

Natural attenuation can reduce contamination of tributyltin (TBT), but persistence of the xenobiotic can cause long-term issues in the environment. Biostimulation is used to accelerate biodegradation. This study investigated the ability of individual organic nutrients and growth factors to enhance TBT biodegradation by sediment microorganisms (SED) and Enterobacter cloacae strain TISTR1971 (B3). The supplements that produced high biomass yield were selected for degradation enhancement. For TBT degradation at initial concentration of 0.1 mg/l, negative or limited degradation was observed in some selected supplements indicating that increasing the biomass did not necessarily promote degradation. Consequently, the addition of nutrients was expected to increase both dioxygenase activity and the degrader population. At different concentrations of supplements, a mixture of succinate/glycerol showed the highest removal for SED which reduced TBT by 77%, 75%, and 68% for 0.1×, 1×, and 10× supplement concentration, respectively. For B3, the addition of succinate showed degradation of 49% (0.1×), 75% (1×), and 77% (10×). Most nutrients and amino acids had an inhibitory effect at 1× or 10× levels. Excess amount of the nutrients added can inhibit the initial degradation of TBT. Therefore, TBT biostimulation requires supplements that increase the capability of TBT degraders at an appropriate amount.

Degradation of hexadecane by Enterobacter cloacae strain TU that secretes an exopolysaccharide as a bioemulsifier.

A Gram-negative rod-shaped bacterium, previously shown to utilize alkanes and polycyclic aromatic hydrocarbons (PAHs), was identified as Enterobacter cloacae (GenBank accession number, GQ426323) by 16S rRNA sequence analysis and was designated as strain TU. During growing on n-hexadecane as the sole carbon source, the strain TU extracellularly released an exopolysaccharide (EPS) exhibiting bioemulsifying activity into the surrounding medium. The EPS was found to be composed of glucose and galactose with molecular weight of 12.4+/-0.4 kDa. The structure of the EPS was postulated according to by 1D/2D NMR, as follows: -D-Glcp-(1 --> 3)-alpha-d-GlcpAc-(1 --> 3)-alpha-D-Galp-(1 --> 4)-alpha-D-Galp-(1 -->. While an enhanced emulsification and aqueous partitioning of n-hexadecane was displayed as functions of the EPS concentration, the EPS neutralized the zeta potential of E. cloacae TU cell and elevated the surface hydrophobicity of the cells, as determined by the microorganisms adhering to hydrocarbon assay (MATH). This was found to favor the bioavailability of n-hexadecane when it served as the sole carbon source for E. cloacae TU and thereby contributed to the accelerated degradation of this hydrocarbon.

[Process fundamentals and field demonstration of wheat straw enhanced biodegradation of petroleum].

A new bioaugmentation method utilizing wheat straw to enhance salt leaching and the subsequent petroleum biodegradation by consortia of bacteria and fungi was proposed. The present study aimed at the effects of wheat straw on the growth and the degradation behavior of E. cloacae and Cun. echinulata, the two species of the consortia. In the laboratory experiments, it was shown that the addition of 5% (mass fraction) straw led to an increase of biomass by 25- and 3-fold to the bacteria and fungi, respectively. The biodegradation ratio of total petroleum hydrocarbon (TPH) was elevated from 29.2% to 48.0% after 468 h treatment. The biodegradation ratio of alkane and aromatic hydrocarbons in petroleum were increased from 31.5% and 39.1%, to 55.7% and 55.9%, respectively. The field demonstration was carried in an area of 6400 m2, in which the bacteria and fungi were inoculated after salt leaching in the presence of wheat straw. The addition of wheat straw in the contaminated soil led to an increase by 158- and 9-fold to the bacteria and fungi, as compared to their counterpart in the controlland without wheat straw, at 25 days after the inoculation. The content of TPH was down to below 0.3% while the maximum biodegradation ratio of TPH reached 75% after 45 days treatment. These results demonstrated the effectiveness and high potential of the wheat straw enhanced bioaugmentation of petroleum-salt contaminated soil.