Aerobic biodegradation of benzene, toluene and ethylbenzene in liquid medium by a bacterial consortium, isolated from non-history clay soil, and their interrelation effect

2000 ◽  
Vol 42 (1-2) ◽  
pp. 25-30
Author(s):  
R. Armon ◽  
T. Arbel ◽  
N. Narkis ◽  
H. Rubin
Keyword(s):  
Liquid Medium ◽  
Aqueous Phase ◽  
Soil Bacteria ◽  
Clay Soil ◽  
Tween 80 ◽  
Bacterial Consortium ◽  
Aerobic Biodegradation ◽  
Second Stage ◽  
Benzene Toluene ◽  
Monoaromatic Hydrocarbons

The present study was carried out in order to investigate the ability of isolated subsurface bacteria, from a non-history clay soil, to biodegrade the non-aqueous phase-liquids (NAPLs), monoaromatic hydrocarbons: benzene, toluene and ethylbenzene. First stage of the study was focussed on stand-alone biodegradation of each contaminant under described conditions. Benzene (100, 260 and 500 mg/l) exposed to isolated soil bacteria for 14 days, was biodegraded 100, 70 and 50%, respectively, ethylbenzene (100, 260 and 500 mg/l) at 85, 87 and 90%, respectively and toluene (100, 260 and 500 mg/l) revealed the lowest rate of 45, 50 and 52%. Toluene and ethylbenzene showed a direct increase in biodegradation associated with increase in their concentration. The second stage was the biodegradation of benzene, toluene and ethylbenzene admixture (all three compounds at the very same concentrations, w/v) in glucose absence and supplemented with Tween 80 (10 and 15 mg/l). The overall biodegradation improved when contaminants were mixed together.

Anaerobic/aerobic biodegradation of pentachlorophenol using GAC fluidized bed reactors: optimization of the empty bed contact time

1997 ◽  
Vol 36 (6-7) ◽  
pp. 107-115 ◽  
Author(s):  
Gregory J. Wilson ◽  
Amid P. Khodadoust ◽  
Makram T. Suidan ◽  
Richard C. Brenner
Keyword(s):  
Fluidized Bed ◽  
Oxygen Demand ◽  
Aerobic Biodegradation ◽  
Fluidized Bed Reactors ◽  
Reactor Performance ◽  
Reactor Operation ◽  
Significant Cost ◽  
Second Stage ◽  
Primary Substrate ◽  
Chlorinated Phenolic Compounds

An integrated reactor system has been developed to remediate pentachlorophenol (PCP) containing wastes using sequential anaerobic and aerobic biodegradation. Anaerobically, PCP was degraded to predominately equimolar concentrations (>99%) of monochlorophenol (MCP) in two GAC fluidized bed reactors at Empty Bed Contact Times (EBCTs) ranging from 18.6 to 1.15 hours. However, at lower EBCTs, MCP concentrations decreased to less than 10% of the influent PCP concentration suggesting mineralization. The optimal EBCT was determined to be 2.3 hours based on PCP conversion to MCPs and stable reactor operation. Decreasing the EBCT fourfold did not inhibit degradation of PCP and its intermediates, thus allowing removal of PCP at much lower detention time and resulting in a significant cost advantage. Analytical grade PCP was fed via syringe pumps into two fluidized bed reactors at influent concentrations of 100 mg/l and 200 mg/l, respectively. Acting as the primary substrate, ethanol was also fed into the reactors at concentrations of 697 and 1388 mg/l. Effluent PCP and chlorinated phenolic compounds were analyzed weekly to evaluate reactor performance. Biodegradation pathways were also identified. 3-chlorophenol (CP) was the predominant MCP and varied simultaneously with 3,5-dichlorophenol (DCP) concentrations. Likewise, 4-CP concentrations varied simultaneously with 3,4-DCP concentrations. A second stage aerobic GAC fluidized bed reactor was added after the anaerobic reactor to completely mineralize the remaining MCP and phenols. Data show no presence of phenol and MCP in the effluent or on the GAC. Overall, the chemical oxygen demand (COD) fed to the system was reduced from 75 g/d in the influent to less than 1.5 g/d in the effluent.

Aerobic Biodegradation of Benzene, Toluene, and Xylene in a Sandy Aquifer-Data Analysis and Computer Modeling

Ground Water ◽  
1989 ◽  
Vol 27 (6) ◽  
pp. 823-834 ◽  
Author(s):  
C. Y. Chiang ◽  
J. P. Salanitro ◽  
E. Y. Chai ◽  
J. D. Colthart ◽  
C. L. Klein
Keyword(s):  
Data Analysis ◽  
Computer Modeling ◽  
Aerobic Biodegradation ◽  
Benzene Toluene ◽  
Sandy Aquifer

Influence of Surfactants on Biodegradation of Chlordane by Wood-Rotting Fungus

2013 ◽  
Vol 361-363 ◽  
pp. 908-911
Author(s):  
Peng Fei Xiao ◽  
Tie Xue You ◽  
Yu Zhen Song ◽  
Shan Ying ◽  
Jian Qiao Wang
Keyword(s):  
Liquid Medium ◽  
Degradation Rate ◽  
Solid Medium ◽  
Fungal Growth ◽  
Tween 80 ◽  
Positive Effects ◽  
Lower Effect ◽  
Triton X

Wood-rotting fungus,Phlebia lindtneriGB 1027, was tested in toxicity assays with three surfactants in order to select surfactants for degradation assays of chlordane. Tween 80 and Triton X-100 appeared to have lower effect on the fungal growth on solid medium, while higher effect of fungal growth was observed in solid medium with SDS. Tween 80 had positive effects both on the chlordane degradation and the fungal growth. When fungus was incubated on PDB liquid medium with Tween 80 of 10 CMC after 20 d, 78.6% of chlordane was removed. In the treatments with Triton X-100, this strain showed comparatively greatest degradation rate (70.8%) of chlordane at a concentration of 2 CMC. However, when Triton X-100 concentration was higher than 2 CMC (5 and 10 CMC), the enhancement for the biodegradation of chlordane decreased.

Carbon Microspheres Prepared by High Internal Phase Emulsion Polymerization

2011 ◽  
Vol 239-242 ◽  
pp. 3105-3108
Author(s):  
Ming Xian Liu ◽  
Li Hua Gan ◽  
Jun Hu ◽  
Hong Lai Liu ◽  
Long Wu Chen
Keyword(s):  
Electron Microscopy ◽  
Specific Surface ◽  
Aqueous Phase ◽  
Apparent Density ◽  
Tween 80 ◽  
Carbon Microspheres ◽  
High Internal Phase Emulsion ◽  
Surface Areas ◽  
Internal Phase ◽  
Specific Surface Areas

In this paper, we present a novel approach for the synthesis of carbon microspheres via the polymerization of a high internal phase emulsion (HIPE). By using Span 80 and Tween 80 as emulsifiers, 1iquid paraffin as oil phase, and the mixture of resorcinol/formaldehyde (R/F) solution as aqueous phase, an O/W emulsion was obtained. This emulsion phase inverted to a W/O HIPE induced by ammonia which served as the polymerization catalyst. Carbon microspheres (CMs) were prepared by polymerization of the HIPE, followed by drying and carbonization. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) analyzer were used to characterize as-prepared CMs. The results indicate that, in case of 0.25 wt% ammonia of the HIPE, the diameters of CMs decreased from about 2 to 1 μm when the mass fraction of aqueous R/F decreased from 0.714 to 0.357; the apparent density and the specific surface areas of the CMs, however, did not change obviously, which are about 0.6 g/cm3and 200 m2/g, respectively. The dosage of ammonia has a significant influence on the morphology and properties of CMs. With increasing of the ammonia mass to 1 wt% of the HIPE, the resultant carbon materials comprise not only CMs, but also some carbon sheets; the apparent density of which increased to 0.9 g/cm3and the specific surface areas of which decreased to below 100 m2/g. In addition, the other parameters for CMs preparation were also investigated. It was found that the proper conditions were controlling the temperature of 303-333 K and the oil/aqueous phase mass ratio of 2.5:7.

scholarly journals Pyrene and Chrysene Tolerance and Biodegradation Capability of Pleurotus Sajor-Caju

2018 ◽  
Vol 12 (1) ◽  
pp. 24-35 ◽  
Author(s):  
Giuliano Saiu ◽  
Stefania Tronci ◽  
Massimiliano Grosso ◽  
Enzo Cadoni ◽  
Nicoletta Curreli
Keyword(s):  
Liquid Medium ◽  
Copper Sulphate ◽  
Negative Impact ◽  
Fungal Growth ◽  
Tween 80 ◽  
White Rot ◽  
White Rot Fungus ◽  
Polycyclic Aromatic ◽  
Pleurotus Sajor Caju

Introduction: The present work focused on the biodegradation capability of a white-rot fungus, the Pleurotus sajor-caju, when exposed to polycyclic aromatic hydrocarbons. Methods: The research was carried out by using in vitro systems developed on Petri dishes, to evaluate the fungal tolerance to pyrene and chrysene, followed by experiments in liquid medium. The first experimental campaign was necessary to evaluate the conditions promoting fungal growth and tolerance (presence of surfactants, peptone, copper sulphate and lecithin) and it was designed and analysed using statistical techniques. Results: It was found that the fungal population growth is strongly inhibited by chrysene presence. On the other hand, pyrene had a mild negative impact on the mycelia growth, which seemed to be positively influenced by the presence of Tween 80 and copper sulphate. Starting from these results, the behaviour of Pleurotus sajor-caju in presence of pyrene was investigated in liquid medium. Results showed that the depletion of pyrene was evident during a period of 20 days, and removal efficiency was greater than 90%.

Aerobic Biodegradation of Aromatic and Chlorinated Hydrocarbons Commonly Detected in Landfill Leachates

1988 ◽  
Vol 23 (3) ◽  
pp. 460-475 ◽  
Author(s):  
Della J. Berwanger ◽  
James F. Barker
Keyword(s):  
Hydrogen Peroxide ◽  
Surface Sediment ◽  
Chlorinated Hydrocarbons ◽  
Aerobic Biodegradation ◽  
Ethyl Benzene ◽  
Landfill Leachates ◽  
Toxic Level ◽  
Benzene Toluene ◽  
Hazardous Organics

Abstract Aromatic and chlorinated hydrocarbons are hazardous organics which persist in groundwater impacted by landfill leachate. Recent studies have indicated that the aromatics biodegrade readily under aerobic conditions. Similarly, methane-oxidizers are reported to metabolize trichloroethylene. This study investigates an in-situ biorestoration scheme involving stimulating aerobic biodegradation in a contaminated anaerobic, methane-saturated groundwater using hydrogen peroxide as an oxygen source. Batch biodegradation experiments were conducted with groundwater and core obtained from the Gloucester Landfill, Ottawa, Canada. Hydrogen peroxide, added at a non-toxic level, provided oxygen which promoted the rapid biodegradation of benzene, toluene, ethyl benzene, o-, m-, and p-xylene. Morphologically different methane-oxidizing cultures were obtained from Gloucester groundwater and a surface sediment. Both cultures degraded trichloroethylene in microcosms containing a mineral media and Gloucester core. Degradation was not observed when the mineral madia was replaced with Gloucester groundwater, or when other chlorinated hydrocarbons were added. Additional research is required to identify and overcome this inhibition to trichloroethylene biodegradation, before this remedial strategy can be employed.

Communal microaerophilic–aerobic biodegradation of Amaranth by novel NAR-2 bacterial consortium

2012 ◽  
Vol 105 ◽  
pp. 48-59 ◽  
Author(s):  
Giek Far Chan ◽  
Noor Aini Abdul Rashid ◽  
Lee Suan Chua ◽  
Norzarini Ab.llah ◽  
Rozita Nasiri ◽  
...  
Keyword(s):  
Bacterial Consortium ◽  
Aerobic Biodegradation

scholarly journals Development of a chemically defined liquid medium for growth of Legionella pneumophila

1979 ◽  
Vol 9 (5) ◽  
pp. 615-626
Author(s):  
L Pine ◽  
J R George ◽  
M W Reeves ◽  
W K Harrell
Keyword(s):  
Liquid Medium ◽  
Legionella Pneumophila ◽  
Ethylenediaminetetraacetic Acid ◽  
Fluorescein Isothiocyanate ◽  
Tween 80 ◽  
Antigen Production ◽  
Maximum Cell ◽  
Legionnaires Disease ◽  
Basal Salts ◽  
Rates Of Growth

A chemically defined liquid medium has been developed for the study of the physiology and antigen production of the Legionnaires disease bacterium. The medium contains basal salts, vitamins, alpha-ketoglutaric acid, pyruvate, 0.05% l-cysteine, 0.05% glutathione, and a mixture of 20 additional amino acids, each of 0.01% final concentration, except serine, which was at 0.1%. The medium in shake culture at 37 degrees C with increased CO2 at pH 6.5, supports the maximum rate of growth, the highest cell yields, and the maximum cell surface antigen as distinguished by specific fluorescein isothiocyanate-conjugated antibody. Studies during the development of this medium showed that CO2, pyruvate, and alpha-ketoglutarate strongly stimulated growth; that cysteine and methionine were required for growth; and that serine, threonine, histidine, tyrosine, and tryptophane were energy sources. Glutathione substituted for cysteine, but cystine did not. The organisms did not use glucose and polysaccharides, as judged by cell yields when these carbohydrates were present or absent. The chelators malate, citrate, and ethylenediaminetetraacetic acid totally inhibited growth. Beta-mercaptoethanol, thioglycolate, dithiothreitol, and Tween 80 (0.05%) inhibited growth strongly or completely. Catalase activity was extremely weak or absent. Morphology varied, depending upon conditions and phases of growth. In general, filamentous forms became chains of cigar-shaped bacilli fragmenting to pairs and becoming coccoidal in the late stationary pha-e of growth. The organism grew at 25, 30, and 37 degrees C. Although they varied in their growth characteristics, 10 isolates were passed for five transfers in the chemically defined broth, giving maximum rates of growth, cell yields, and antigen production.

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