Quinoline Biodegradation Research Articles

Accelerating Quinoline Biodegradation and Oxidation with Endogenous Electron Donors.

Quinoline, a recalcitrant heterocyclic compound, is biodegraded by a series of reactions that begin with mono-oxygenations, which require an intracellular electron donor. Photolysis of quinoline can generate readily biodegradable products, such as oxalate, whose bio-oxidation can generate endogenous electron donors that ought to accelerate quinoline biodegradation and, ultimately, mineralization. To test this hypothesis, we compared three protocols for the biodegradation of quinoline: direct biodegradation (B), biodegradation after photolysis of 1 h (P1h+B) or 2 h (P2h+B), and biodegradation by adding oxalate commensurate to the amount generated from photolysis of 1 h (O1+B) or 2 h (O2+B). The experimental results show that P1h+B and P2h+B accelerated quinoline biodegradation by 19% and 50%, respectively, compared to B. Protocols O1+B and O2+B also gave 19% and 50% increases, respectively. During quinoline biodegradation, its first intermediate, 2-hydroxyquinoline, accumulated gradually in parallel to quinoline loss but declined once quinoline was depleted. Mono-oxygenation of 2-hydroxyquinoline competed with mono-oxygenation of quinoline, but the inhibition was relieved when extra electrons donors were added from oxalate, whether formed by UV photolysis or added exogenously. Rapid oxalate oxidation stimulated both mono-oxygenations, which accelerated the overall quinoline oxidation that provided the bulk of the electron donor.

Novel porous polyethersulfone beads as matrix to immobilize Comamonas testosteroni sp. bdq06 in quinoline biodegradation

Novel matrix beads for the immobilization of strain Comamonas testosteroni sp. bdq06 to degrade quinoline were fabricated from polyethersulfone(PES). The beads have an average size of 3 mm and a surface dense layer of 20 microns. To help adhesion and proliferation of bacterial cells, the surfaces of the PES beads were etched, and numerous holes about 1.5 micrometers in diameter were generated as tunnels for cell colonizing in the larger internal cavities of about 5 micrometers in diameter. The quinoline degradation was remarkably enhanced by the cells immobilized in PES beads compared with that by the free cells at pH 5.0 or 10.0 and a temperature of 40 °C. The enhanced degradation of quinoline was contributed to the biofilm on the surface of PES beads, resulting in the significant reduction of retention time from 9 h to 2 h. Furthermore, the beads remain intact after the ultrasonic treatment of them for 30 min or recycling 50 times, indicating that they have excellent mechanical strength, flexibility and swelling capacity. Thus, PES beads have great potential to be matrix for the cell immobilization in bioaugmentation.

Biodegradation of Various Aromatic Compounds by Enriched Bacterial Cultures: Part B--Nitrogen-, Sulfur-, and Oxygen-Containing Heterocyclic Aromatic Compounds.

Present study focused on the biodegradation of various heterocyclic nitrogen, sulfur, and oxygen (NSO) compounds using naphthalene-enriched culture. Target compounds in the study were pyridine, quinoline, benzothiophene, and benzofuran. Screening studies were carried out using different microbial consortia enriched with specific polycyclic aromatic hydrocarbon (PAH) and NSO compounds. Among different microbial consortia, naphthalene-enriched culture was the most efficient consortium based on high substrate degradation rate. Substrate degradation rate with naphthalene-enriched culture followed the order pyridine > quinoline > benzofuran > benzothiophene. Benzothiophene and benzofuran were found to be highly recalcitrant pollutants. Benzothiophene could not be biodegraded when concentration was above 50 mg/l. It was observed that 2-(1H)-quinolinone, benzothiophene-2-one, and benzofuran-2,3-dione were formed as metabolic intermediates during biodegradation of quinoline, benzothiophene, and benzofuran, respectively. Quinoline-N and pyridine-N were transformed into free ammonium ions during the biodegradation process. Biodegradation pathways for various NSO compounds are proposed. Monod inhibition model was able to simulate single substrate biodegradation kinetics satisfactorily. Benzothiophene and benzofuran biodegradation kinetics, in presence of acetone, was simulated using a generalized multi-substrate model.

Biodegradation of quinoline by Streptomyces sp. N01 immobilized on bamboo carbon supported Fe3O4 nanoparticles

A novel immobilizing carrier, bamboo-carbon supported Fe3O4 nanoparticles (Fe3O4/BC), was developed and used for immobilization of cells of a quinoline-degrading, Streptomyces sp. N01. The performance of Fe3O4/BC immobilized cells in the degradation of quinoline was evaluated and compared with bamboo-carbon immobilized cells and the free cells. Experiments were performed at various quinoline concentrations (100–400mg/L), pH (5–10) and temperature (20–45°C). The results show that Fe3O4/BC immobilized cells could tolerate a higher quinoline concentration and protect the bacteria much more effectively against changes in temperature and pH. Reusability results revealed that quinoline removal was maintained 85.3% in the ninth cycle. These results demonstrated that Fe3O4/BC possesses a good application potential as a carrier in cell immobilization.

Coupled aerobic and anoxic biodegradation for quinoline and nitrogen removals

Quinoline (C9H7N) commonly occurs in wastewaters from the chemical, pharmaceutical, and dyeing industries. As quinoline is biodegraded, nitrogen is released as ammonium. Total-N removal requires that the ammonium-N be nitrified and then denitrified. The objective of this study was to couple quinoline biodegradation with total-N removal. In a proof-of-concept step, activated sludge was sequenced from aerobic to anoxic stages. The ammonium nitrogen released from quinoline biodegradation in the aerobic stage was nitrified to nitrate in parallel. Anoxic biodegradation of the aerobic effluent then brought about nitrogen and COD removals through denitrification. Then, simultaneous quinoline biodegradation and total-N removal were demonstrated in a novel airlift internal loop biofilm reactor (AILBR) having aerobic and anoxic zones. Experimental results showed that the AILBR could achieve complete removal of quinoline, 91% COD removal, and 85% total-N removal when glucose added as a supplemental electron donor once nitrate was formed.

Isolation and Degradation Kinetics of the Quinoline Degradation Bacterium Strains from Coking Wastewater

An aerobic bacterial strain Q1 capable of utilizing quinoline as sole source of carbon, nitrogen and energy was isolated from activated sludge of a coke plant wastewater treatment process. The morphological properties and the phylogenetic analysis based on 16S rDNA sequences showed strain Q1 belonged to thePseudomonassp.. Another strain Q2 was unable to utilize quinoline as sole source of energy alone can coexist with Q1 when quinoline was sole energy. The coexistence of Q1 and Q2 has synergistic effect to quinoline degradation. The biodegradation tests suggested that the kinetics of quinoline biodegradation by Q1 or the combaination of Q1and Q2 strain can be described by Haldane equation kinetically.

Interaction and biodegradation evaluate of m-cresol and quinoline in co-exist system

Environmentally hazardous and toxic chemicals are commonly generated in actual wastewater that the complex compositions in wastewater treatment system need different types of strains to be degraded. The main objective of this research was to understand the effect of extra substrates, phenolic and N-heterocyclic compounds, on the performance of pure cultural and mixed strains under single and dual substrates conditions. Two bacteria, Lysinibacillus sp. SC03 and Achromobacter sp. DN-06, were acclimated to degrade different concentrations of m-cresol and quinoline. The results indicated that Lysinibacillus sp. SC03 could completely degrade 100 mg l−1m-cresol with no delay time, however, little removal of quinoline was observed; Achromobacter sp. DN-06 could degrade 100 mg l−1 quinoline in 32 h, but could not remove m-cresol, which means m-cresol and quinoline is the specific substrate. The degradation rate of m-cresol fitted well to the zero-order kinetic equation although the degrading ability of Lysinibacillus sp. SC03 was inhibited when less than 100 mg l−1 quinoline was added, and the inhibitive effect was confirmed to be a noncompetitive pattern which could be interpreted by the Michaelis–Menten kinetics equation with corresponding parameters Vmax, Km, K1 and K2 were 13.16 mg l−1 h−1, 35.84 mg l−1, 200.0 mg l−1 and 285.7 mg l−1, respectively. Moreover, the addition of m-cresol-degrading strain (Lysinibacillus sp. SC03) could accelerate the removal of quinoline because the metabolites of quinoline could be degraded by Lysinibacillus sp. SC03 and the chemical equilibrium moved to more biodegradation of quinoline. Also, this process attributed to less the delay time during the quinoline removal.

UV photolysis for accelerated quinoline biodegradation and mineralization

Sequentially and intimately coupled photolysis with biodegradation were evaluated for their ability to accelerate quinoline-removal and quinoline-mineralization kinetics. UV photolysis sequentially coupled to biodegradation significantly improved biomass-growth kinetics, which could be represented well by the Aiba self-inhibition model: UV photolysis increased the maximum specific growth rate (μ max) by 15 %, and the inhibition constant (K SI) doubled. An internal loop photo-biodegradation reactor (ILPBR) was used to realize intimately coupled photolysis with biodegradation. The ILPBR was operated with batch experiments following three protocols: photolysis alone (P), biodegradation alone (B), and intimately coupled photolysis and biodegradation (P&B). For P&B, the maximum quinoline removal rate (r max) increased by 9 %, K SI increased by 17 %, and the half-maximum-rate concentration (K S) decreased by 55 %, compared to B; the composite result was a doubling of the quinoline-biodegradation rate for most of the concentration range tested. The degree of mineralization was increased by both forms of photolysis coupled to biodegradation, and the impact was greater for intimate coupling (18 % increase) than sequential coupling (5 %). The benefits of UV photolysis were greater with intimate coupling than with sequential coupling due to parallel transformation by biodegradation and photolysis.

Biodegradation characteristics and bioaugmentation potential of a novel quinoline-degrading strain of Bacillus sp. isolated from petroleum-contaminated soil

Quinoline and its derivatives are widely considered to be environmental pollutants. In this study, the biodegradation characteristics and bioaugmentation potential for a novel strain were described. The strain, named Q2, which could utilize quinoline as the sole carbon, nitrogen and energy source, was isolated and identified as a Bacillus sp. The optimum temperature, initial pH and shaker rotary speed for quinoline degradation were 30°C, pH 8–10 and 100–200rpm, respectively. During the biodegradation process, the quinoline-N was released as ammonium and the culture broth became yellow, pink and brown in turn, which indicated that several intermediates were generated. GC/MS analysis showed that 2(1H)-quinolinone and 8-hydroxycoumarin were produced. Furthermore, the bioaugmentation of Q2 into the sludge consortium, which was taken from refinery wastewater treatment plant, to degrade quinoline was investigated. The results showed that it could coexist with the other microbes and the remarkably enhanced quinoline biodegradation ability was achieved.

Efficient bioconversion of compactin to pravastatin by the quinoline-degrading microorganism Pseudonocardia carboxydivorans isolated from petroleum-contaminated soil

Pravastatin is one of the first available statins on the market. The purpose of this study was to isolate and identify the quinoline-degrading microorganism from petroleum-contaminated soil that could bioconvert compactin to pravastatin. There were 10,011 microorganism colonies isolated; five strains showed a higher capability for quinoline biodegradation. These five strains were evaluated for their pravastatin bioconversion ability; Pseudonocardia sp. had the highest efficiency for conversion of compactin to pravastatin. The strain was further identified as Pseudonocardia carboxydivorans PAH4. The bioconversion rates were studied under difference incubation conditions. Pre-incubation in medium containing 0.005% compactin sodium, resulted in the compactin utilization rate of almost 100% in a 1mg/ml compactin-containing medium. The rate of conversion of pravastatin was up to 68% after 6days of incubation. In conclusion, the results of this study suggest that P. carboxydivorans PAH4 could be considered a candidate for the production of pravastatin on an industrial scale.

Rapid Determination of Quinoline and 2-Hydroxyquinoline in Quinoline Biodegradation Process by Tri-Wavelength UV/Vis Spectroscopy

For the present study, a tri-wavelength UV/Vis spectrophotometric method for rapid determination of quinoline (Q) and 2-hydroxyquinoline (HQ) during Q biodegradation was developed. Based on the spectral measurements at 289 nm (the isosbestic point of Q and HQ), 326 and 380 nm, the spectral interference of extracellular polymeric substances (EPS) in the process samples could be minimized, and the amounts of Q and HQ could be simultaneously quantified. Our results indicated that the relative standard deviations in the repeatability tests were 2.7 and 1.7% for Q and HQ, respectively. The method validation was conducted by comparing the data obtained using the present method with those generated from high performance liquid chromatography (HPLC). The same set of samples from Q biodegradation process was used. The relative differences between the two methods were within 10%. In conclusion, the present method is simple, rapid, and suitable for the investigation in Q biodegradation processes.

Carbon and hydrogen isotope fractionation during anaerobic quinoline degradation

Quinoline is a N-heterocyclic compound often found at tar oil contaminated field sites. To provide information whether stable isotope analysis can help to characterize the fate of quinoline within contaminated aquifers, carbon and hydrogen isotope fractionation of quinoline were investigated during biodegradation under sulfate-reducing conditions. No significant carbon isotope effect was observed, however, substantial hydrogen isotope fractionation was detected. Thus, hydrogen isotope fractionation may be used as an indicator for in situ biodegradation of quinoline. The bulk hydrogen isotope enrichment factor was εH bulk = −33 ± 12 ‰. During the biodegradation of quinoline the primary intermediate 2-hydroxyquinoline was detected indicating hydroxylation at the C2-position. According to this reaction mechanism, the reactive position specific hydrogen enrichment factor ( εH reactive position) and apparent kinetic hydrogen isotope effect (AKIE H) were calculated and gave values of εH reactive position = −205 ± 75 ‰ and AKIE H = 1.26 ± 0.12, respectively. The missing carbon isotope effect may be explained by strong masking or an enzymatic direct side-on insertion of oxygen from the Mo OH(H) group of the molybdenum center across the C H bond at the C2-position of quinoline with concomitant hydride transfer. The later assumption is supported by recent studies showing that initial step of hydroxylation of N-heteroaromatic compounds proceeds via a similar reaction mechanism.

Biodegradation characteristics of quinoline by Pseudomonas putida

A quinoline-degrading strain was isolated from activated sludge of the municipal wastewater treatment plant and identified as Pseudomonas putida on the basis of its partial 16S rRNA gene sequence analysis. The characteristics of quinoline degradation were investigated. The experimental results showed that quinoline at the concentration of 500 mg/L could be completely removed within 3 h, but could not be mineralized because special pigments were observed in the process of quinoline biodegradation. The N-atom in the quinoline ring was released as NH 3; some metabolic intermediates were identified, including 2-hydroxyquinoline, 2,8-dihydroxyquinoline and 8-hydroxycoumarin. The metabolic pathway of quinoline by P. putida was tentatively proposed, that is, via 8-hydroxycoumarin pathway, namely, the biodegradation was initiated by hydroxylation at position 2 to form 2-oxo-1,2-dihydroquinoline (2-hydroxyquinoline), which was then oxidized to 8-hydroxy-2-oxo-1,2-dihydro-quinoline (2,8-dihydroxyquinoline) and 8-hydroxycoumarin.

Quinoline Biodegradation by Bacillus Licheniformis Strain CRC-75

A bacterial culture was isolated from oil-contaminated soil based on its ability to metabolize the quinoline as the sole source of nitrogen. In this research Bacillus licheniformis strain was identified based on the result of 16S rRNA analysis. Optimized conditions were obtained with full factorial experimental design method using design expert software at temperature: 32 o C, agitation speed: 200rpm, quinoline concentration: 400 ppm.The efficiency of Bacillus licheniformis for biodegradation of quinoline at the optimum conditions was determined to be 35%. Two-phase cultivation media were used with 5, 10, 15 and 20% heavy crude oil concentration in aqueous media. Resting cells of Bacillus licheniformis was shown to be capable of removing about 25% of total nitrogen in 5% heavy crude oil. GC analysis showed a decreasing trend in the activity of this strain against crude oil concentration

Removal of pyridine and quinoline by bio-zeolite composed of mixed degrading bacteria and modified zeolite

In the process of the biodegradation of pyridine and quinoline, ammonium is often generated because of the transformation of N from pyridine and quinoline. Zeolite has been proven to be an effective sorbent for the removal of the ammonium. The natural zeolite can be modified to be the macroporous carrier in the biological wastewater treatment process. In this study, a specific bio-zeolite composed of mixed bacteria (a pyridine-degrading bacterium and a quinoline-degrading bacterium) and modified zeolite was used for biodegradation and adsorption in two types of wastewater: sterile synthetic and coking wastewater. The experimental results indicated that pyridine and quinoline could be degraded simultaneously by the mixed bacteria. Furthermore, NH 4 +-N transformed from pyridine and quinoline could be removed by the modified zeolite. In addition, the bacterial community structures of the coking wastewater and the bio-zeolite were monitored by the amplicon length heterogeneity polymerase-chain reaction (LH-PCR) technique. Both LH-PCR results and scanning electron microscope (SEM) observations indicated that the microorganisms, including BW001 and BW003, could be easily attached on the surface of the modified zeolite and that the bio-zeolite could be used in the treatment of wastewater containing pyridine and/or quinoline.

Electricity production from and biodegradation of quinoline in the microbial fuel cell

Quinoline has become one of the common contaminants in groundwater and soil, discharged from the process of coal tar distillation and creosote wood preservation, as well as fossil fuel facilities. The aim of this study was to investigate the feasibility of electricity production from and biodegradation of quinoline in the microbial fuel cell (MFC). Experiments were conducted in the MFC using an initial 500 mg/L quinoline with different glucose concentrations as substrates. Results showed maximum voltages of 558, 469, and 328 mV for the substrates with ratios of quinoline to glucose of 1:1, 5:3, 5:1, respectively. The MFC accomplished complete quinoline biodegradation within 6 h. Experiments were then conducted using 200 mg/L quinoline only as the MFC fuel, resulting in the maximal voltage of 145 mV and maximal power density of 16.4 mW/m2. GC/MS analyses showed that 2(1H)quinolinone accumulated in the anode solution and later disappeared. The results clearly demonstrated the feasibility to use quinoline as the MFC fuel to generate electricity and enhance quinoline biodegradation simultaneously.

Quinoline biodegradation and its nitrogen transformation pathway by a Pseudomonas sp. strain

A Pseudomonas sp. strain, which can utilize quinoline as its sole carbon, nitrogen and energy source, was isolated from activated sludge in a coking wastewater treatment plant. Quinoline can be degraded via the 8-hydroxycoumarin pathway. We quantified the first two organic intermediates of the biodegradation, 2-hydroxyquinoline and 2,8-dihydroxyquinoline. We tracked the transformation of the nitrogen in quinoline in two media containing different C/N ratios. At least 40.4% of the nitrogen was finally transformed into ammonium when quinoline was the sole C and N source. But addition of an external carbon source like glucose promoted the transformation of N from NH3 into NO3(-), NO2(-), and then to N2. The product analysis and gene characteristics indicated that the isolate accomplished heterotrophic nitrification and aerobic denitrification simultaneously. The study also demonstrated that quinoline and its metabolic products can be eliminated if the C/N ratio is properly controlled in the treatment of quinoline-containing wastewater.

Nitrate-dependent biodegradation of quinoline, isoquinoline, and 2-methylquinoline by acclimated activated sludge

The anaerobic degradation of quinoline, isoquinoline and 2-methylquinoline was investigated under nitrate-reducing conditions with acclimated activated sludge. Quinoline was completely transformed during degradation with an optimum COD/NO(3)-N ratio of 7. Isoquinoline and 2-methylquinoline were also completely transformed; however, nitrate consumption was much lower with the optimum COD/NO(3)-N ratios being in the ranges of 83-92 and 21-26, respectively. GC-MS analyses showed that during degradation, quinoline and isoquinoline were transformed by hydroxylation into 2(1H)-quinolinone and 1(2H)-isoquinolinone, respectively. While quinoline was completely mineralized, only 92% of isoquinoline was mineralized, and 1(2H)-isoquinolinone remained in the effluent. 2-Methylquinoline was transformed by hydrogenation to 1,2,3,4-tetrahydro-2-methyl-quinoline, and further degradation resulted in cleavage of the heterocyclic ring leaving 4-ethyl-benzenamine. Both the metabolites remained in the effluent, resulting in the low mineralization of 2-methylquinoline (58%). This is the first time that 2-methylquinoline is observed degradable under denitrifying conditions, and its metabolites are identified.

Simultaneous biodegradation of pyridine and quinoline by two mixed bacterial strains

Experiments were conducted to provide data on the effectiveness of bioaugmentation in the removal of pyridine and quinoline from different wastewaters. A pyridine-degrading bacterial strain (Paracoccus sp. BW001) and a quinoline-degrading strain (Pseudomonas sp. BW003) were isolated from the activated sludge of a coking wastewater treatment plant. In this study, a consortium of these two bacterial strains was used as inoculum to simultaneously degrade pyridine and quinoline in three types of wastewaters: sterile synthetic, domestic, and industrial. In addition, variation of the bacterial community structures during degradation was monitored by denaturing gradient gel electrophoresis and amplicon length heterogeneity polymerase chain reaction techniques. The results of our experiments indicate that pyridine and quinoline can be removed efficiently using this inoculum but that the degradation process results in the production of ammonium as a by-product. Also, in the two actual wastewaters investigated, we observed that several autochthonous strains of bacteria in both the domestic and industrial wastewater were tolerant of pyridine and quinoline and grew rapidly.

고정화된 Bacillus Brevis에 의한 큐놀린 분해의 증가

유리 및 고정화된 Bacillus brevis에 의한 큐놀린의 분해를 조사하였다. 코코넛 껍질 탄소에 고정화된 Bacillus brevis에 의한 큐놀린 분해 속도는 폼조각에 고정화되었거나 유리된 미생물에 의한 속도보다 빠르다. 시료에 존재하는 큐놀린 100 ppm을 완전히 제거하기 위해서는 코코넛 껍질 탄소에 고정화된 Bacillus brevis로 만든 생촉매를 물속에서 20시간 유지시키면 되었다. 이 생촉매는 꽤 긴 보존기간과 적절한 재생력을 가지고 있었다. Biodegradation of Quinoline by free and immobilized Bacillus brevis has been investigated. The rate of quinoline degradation by immobilized Bacillus brevis on coconut shell carbon is faster than the rate by the microorganism immobilized on foam pieces and free cells. A complete removal of 100 ppm of Quinoline in the sample was achieved at a hydraulic retention time of 20 hours with the biocatalyst prepared by immobilizing Bacillus brevis onto coconut shell carbon. The biocatalyst had a reasonable shelf life and desirable recycle capacity.