Degradation of phenol by a bacterial consortium under methanogenic conditions

1990 ◽  
Vol 36 (8) ◽  
pp. 573-578 ◽  
Author(s):  
G. Béchard ◽  
J.-G. Bisaillon ◽  
R. Beaudet ◽  
M. Sylvestre
Keyword(s):  
Key Words ◽  
Culture Medium ◽  
Degradation Products ◽  
Phenol Degradation ◽  
Bacterial Consortium ◽  
Energy Sources ◽  
Gram Negative ◽  
Proteose Peptone ◽  
Large Numbers ◽  
Anaerobic Consortium

An anaerobic bacterial consortium was shown to carboxylate phenol to benzoate under methanogenic conditions. Benzoate accumulated in the culture medium and was completely degraded when the incubation period was prolonged. Two potential intermediates of phenol metabolism, namely cyclohexanol and cyclohexanone, were not accumulated or transformed by the consortium. Proteose peptone must be added to the culture medium for the carboxylation of phenol to occur and glucose could not replace proteose peptone. Inhibition of methanogenesis did not affect the carboxylation of phenol and the presence or absence of hydrogen in the gaseous atmosphere did not prevent the accumulation of benzoate. The consortium was composed of various microbiological forms dominated by Gram-negative rods. Phenol-carboxylating microorganisms were evaluated to about ≥ 1 × 108 cells/mL by using diluted inocula. These results suggest that the carboxylation of phenol is accomplished by co-metabolism and that proteose peptone or some degradation products serve as carbon and energy sources for the growth of the carboxylating bacteria, which appear to be present in large numbers in the consortium. Key words: phenol, degradation, anaerobic, consortium, methanogenesis.

Removal of phenolic compounds from a petrochemical effluent with a methanogenic consortium

1999 ◽  
Vol 45 (3) ◽  
pp. 235-241 ◽  
Author(s):  
A Charest ◽  
J -G Bisaillon ◽  
F Lépine ◽  
R Beaudet
Keyword(s):  
Phenolic Compounds ◽  
Phenol Degradation ◽  
Ammoniacal Nitrogen ◽  
Hydraulic Residence Time ◽  
Batch Cultures ◽  
Proteose Peptone ◽  
Effluent Toxicity ◽  
Anaerobic Consortium ◽  
Very High ◽  
Methanogenic Consortium

A methanogenic consortium was used to degrade phenol and ortho- (o-) cresol from a specific effluent of a petrochemical refinery. This effluent did not meet the local environmental regulations for phenolic compounds (178 mg/L), oils and greases (61 mg/L), ammoniacal nitrogen (75 mg/L) or sulfides (3.2 mg/L). The consortium, which degrades phenol via its carboxylation to benzoic acid, was progressively adapted to the effluent. Despite the very high effluent toxicity (EC50 of 2% with Microtox), the adapted consortium degraded 97% of 156 mg/L phenol in the supplemented effluent after 13 days in batch cultures (serum bottle). The addition of proteose peptone to the effluent is essential for phenol degradation. o-cresol was also transformed but not meta- or para-cresols. A continuous flow fixed-film anaerobic bioreactor was developed with the consortium. Treating the effluent with the bioreactor reduced phenol and phenolic compounds concentrations by 97 and 83%, respectively, for a hydraulic residence time of 6 h. This treatment also reduced by about half the effluent toxicity. Oils and greases and ammoniacal nitrogen were not affected. Similar microbiological forms were observed in serum bottles and in the bioreactors with or without the petrochemical effluent. These results indicate that this methanogenic consortium can treat efficiently the phenolic compounds in this specific petrochemical effluent.Key words: phenolic compounds, anaerobic consortium, petrochemical effluent, biodegradation, methanogenic conditions.

Study of the methanogenic degradation of phenol via carboxylation to benzoate

1991 ◽  
Vol 37 (7) ◽  
pp. 573-576 ◽  
Author(s):  
Jean-Guy Bisaillon ◽  
François Lépine ◽  
Réjean Beaudet
Keyword(s):  
Fatty Acids ◽  
Sodium Bicarbonate ◽  
Key Words ◽  
Yeast Extract ◽  
Volatile Fatty Acids ◽  
Bacterial Consortium ◽  
Proteose Peptone ◽  
Benzoate Degradation ◽  
Dead End ◽  
Cyclohexane Carboxylate

An anaerobic bacterial consortium carboxylating phenol to benzoate by cometabolism in the presence of proteose peptone under methanogenic conditions was studied. Yeast extract or a mixture of tryptophan and lysine could replace proteose peptone without affecting the carboxylating activity, whereas glucose, glycerol, pyruvate, volatile fatty acids, and sodium bicarbonate could not. The carboxylating microorganism could not be obtained pure from the phenol culture supplemented with tryptophan and lysine; six different morphological types of microorganisms were able to grow in this medium. The results obtained with potential intermediates of benzoate degradation given as substrates to the consortium suggest that benzoate is transformed to 1-cyclohexene carboxylate and to heptanoate. Part of 1-cyclohexene carboxylate was transformed to an apparent dead-end product identified as cyclohexane carboxylate. Key words: phenol, carboxylation, benzoate, methanogenic conditions.

Nitrification: an old process, a new concern

1971 ◽  
Vol 24 ◽  
Author(s):  
W. H. Verstraete
Keyword(s):  
Culture Medium ◽  
Nitrogen Sources ◽  
Living Cells ◽  
Factors Affecting ◽  
Inhibiting Effect ◽  
Proteose Peptone ◽  
Asparaginase Activity

Some  factors affecting the L-asparaginase activity of E.  aroideae were investigated. Increasing  concentrations of glucose in the culture medium had an inhibiting effect on  the production of L-asparaginase by this microorganism. Buffering of the  culture medium in order to stabilize the pH during growth resulted in a decrease  of the L-asparaginase activity. From the different nitrogen sources examined,  tryptone, proteose peptone nr 2 and nr 3 stimulated the L-asparaginase  production. Toluene treatment of the cells practically destroyed the  L-asparaginase. Acetone dried cells showed an L-asparaginase activity  comparable with the activity of living cells.

In Vitro Removal of Ochratoxin A by Wine Lactic Acid Bacteria

2007 ◽  
Vol 70 (9) ◽  
pp. 2155-2160 ◽  
Author(s):  
VINCENZO DEL PRETE ◽  
HECTOR RODRIGUEZ ◽  
ALFONSO V. CARRASCOSA ◽  
BLANCA de las RIVAS ◽  
EMILIA GARCIA-MORUNO ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Ochratoxin A ◽  
High Performance ◽  
Culture Medium ◽  
Degradation Products ◽  
Cell Binding ◽  
A Cell ◽  
In Vitro Interaction

A study was carried out to determine the in vitro interaction between ochratoxin A (OTA) and wine lactic acid bacteria (LAB). Fifteen strains belonging to five relevant oenological LAB species were grown in liquid synthetic culture medium containing OTA. The portion of OTA removed during the bacterial growth was 8 to 28%. The OTA removed from the supernatants was partially recovered (31 to 57%) from the bacterial pellet. Cell-free extracts of three representative strains were produced by disrupting cells in a French pressure cell. The ability of crude cell-free extracts to degrade OTA was studied. OTA was not degraded by cell-free extracts of wine LAB strains, and no degradation products of OTA were detected in the high-performance liquid chromatograms of the methanol extract of the bacterial pellet. On the basis of these results, we conclude that OTA removal by wine LAB is a cell-binding phenomenon. The chemistry and the molecular basis of OTA binding to wine LAB remains unknown.

Synthesis and action of nitric oxide in rat glomerular mesangial cells

1991 ◽  
Vol 261 (4) ◽  
pp. F600-F606 ◽  
Author(s):  
P. J. Shultz ◽  
M. A. Tayeh ◽  
M. A. Marletta ◽  
L. Raij
Keyword(s):  
Nitric Oxide ◽  
Culture Medium ◽  
Mesangial Cells ◽  
Culture Media ◽  
Degradation Products ◽  
Specific Inhibitor ◽  
Cgmp Level ◽  
Glomerular Mesangial Cells ◽  
Intracellular Cgmp ◽  
Stimulation Of

Macrophages and certain tumor cell lines can be induced to synthesize nitric oxide (NO) from L-arginine after stimulation with lipopolysaccharide (LPS) or cytokines. In the present study, we have found that culture medium collected after 24 h from unstimulated rat mesangial cells (MC) contains 6.3 +/- 1.2 microM of NO3-/NO2- (the degradation products of NO). These levels were significantly increased when MC were incubated with LPS (10 micrograms/ml) for 24 h (23.9 +/- 4.1, P less than 0.05). The specific inhibitor of NO synthesis, NG-monomethyl-L-arginine (L-NMMA) completely inhibited LPS-stimulated production of NO3-/NO2-, confirming that the NO3-/NO2- was derived from NO within the MC. Recent studies suggest that endothelium-derived relaxing factor (EDRF) produced by vascular endothelium is also NO, and we have previously shown that both EDRF and NO stimulate increases in MC guanosine 3',5'-cyclic monophosphate (cGMP). Thus we sought to determine whether NO synthesized by the MC could affect cGMP levels within the same cells. After 24-h incubation with LPS (10 micrograms/ml), intracellular cGMP level within the MC was 706.3 +/- 197 (SE) compared with 40.5 +/- 7 fmol/micrograms protein in control MC incubated in media alone (P less than 0.01). The changes in cGMP in response to LPS were inhibited by greater than 90% by L-NMMA. Similar to LPS, incubation of MC with the cytokine gamma-interferon also increased NO3-/NO2- in the culture media and increased cGMP levels within MC. The induction of NO synthesis within MC and the concomitant stimulation of MC cGMP may be important in the modulation of the effects of endotoxemia, as well as inflammation, within the glomerulus.

scholarly journals Glass beads load macromolecules into living cells

1987 ◽  
Vol 88 (5) ◽  
pp. 669-678
Author(s):  
P.L. McNeil ◽  
E. Warder
Keyword(s):  
Culture Medium ◽  
Small Volume ◽  
Cultured Cells ◽  
Cell Monolayer ◽  
Cell Loss ◽  
Living Cells ◽  
Glass Beads ◽  
Cell Type ◽  
Large Numbers ◽  
Micron Diameter

We describe and characterize an exceptionally rapid and simple new technique for loading large numbers of cultured cells with large macromolecules. The culture medium of the cell monolayer is replaced by a small volume of the macromolecule to be loaded. Glass beads (75–500 micron diameter) are then sprinkled onto the cells, the cells are washed free of beads and exogenous macromolecules, and ‘bead-loading’ is completed. The conditions for bead-loading can readily be modified to accommodate cell type and loading objectives: for example, the amount of loading per cell increases if bead size is increased or if beads are agitated after sprinkling onto the monolayer, but at the expense of increased cell loss. As many as 97% of a population of bovine aortic endothelial (BAE) cells were loaded with a 10,000 Mr dextran; and 79% with a 150,000 Mr dextran using bead-loading. Various cell lines have been loaded using glass beads. Moreover, bead-loading has the advantage of producing loaded cells that remain adherent and well-spread, thus minimizing recovery time and permitting immediate microscopic examination.

scholarly journals Biodegradation of two organic UV-Filters by single bacteria strains

2021 ◽  
Author(s):  
Florentina Laura Chiriac ◽  
Catalina Stoica ◽  
Iuiana Paun ◽  
Florinela Pirvu ◽  
Toma Galaon ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Emerging Contaminants ◽  
Degradation Products ◽  
Aquatic Organisms ◽  
Uv Filters ◽  
Bacterial Strains ◽  
Gram Negative ◽  
Biodegradation Process ◽  
Salmonella Thyphimurium ◽  
Organic Uv Filters

Abstract Organic UV-filters, including 4-hydroxybenzophenone (4-HBP) and 2,4-dihydroxybenzophenone (BP-1), are persistent emerging contaminants whose presence in the environment poses a threat to aquatic organisms due to their endocrine disruptor’s properties. For this reason, finding suitable technological processes for their safety and efficient removal from the environment represent a priority for the scientific community. To the author’s knowledge, until now, there are no studies reporting the biodegradation of 4-HBP and BP-1 by a single bacteria strain. In this paper, there were tested the 4-HBP and BP-1 biodegradation potential of two Gram-positive (Staphylococcus aureus and Enterococcus faecalis) and two Gram-negative (Salmonella typhimurium and Serratia rubidae). The 4-HPB biodegradation process was observed only in the presence of Gram-negative bacterial strains. Thus, the biodegradation rates of 4-HBP reached up to 12.7% after 24h of incubation in presence of Salmonella thyphimurium and up to 24.0% after 24h of incubation with Serratia rubidae. Staphylococcus aureus was able to biodegrade 26.7% of BP-1, while Salmonella thiphymurium was able to biodegrade 14.7% of BP-1 after 24h of incubation. Their biodegradation products generated during the 4-HBP biodegradation process by Serratia rubidae were analyzed through LC-MS/MS analysis. The (bio)degradation products were benzophenone and a multi-hydroxylated derivative of 4-HBP and the degradation pathways were proposed. The data obtained in this study gave important information regarding the 4-HBP and BP-1 potential biodegradation by single bacterial strains.

A New Approach of Rpf Addition to Explore Bacterial Consortium for Enhanced Phenol Degradation Under High Salinity Conditions

2018 ◽  
Vol 75 (8) ◽  
pp. 1046-1054 ◽  
Author(s):  
Ziqiao Li ◽  
Yunge Zhang ◽  
Yuyang Wang ◽  
Rongwu Mei ◽  
Yu Zhang ◽  
...  
Keyword(s):  
High Salinity ◽  
Phenol Degradation ◽  
Bacterial Consortium ◽  
New Approach

Isolation of Moraxella canis from an Ulcerated Metastatic Lymph Node

2000 ◽  
Vol 38 (10) ◽  
pp. 3870-3871 ◽  
Author(s):  
Mario Vaneechoutte ◽  
Geert Claeys ◽  
Sophia Steyaert ◽  
Thierry De Baere ◽  
Renaat Peleman ◽  
...  
Keyword(s):  
Lymph Node ◽  
Metastatic Lymph Node ◽  
Upper Airway ◽  
Blood Cultures ◽  
Human Isolate ◽  
Supraclavicular Lymph Node ◽  
Gram Negative ◽  
The Third ◽  
Terminal Patient ◽  
Large Numbers

Moraxella canis was isolated in large numbers from an ulcerated supraclavicular lymph node of a terminal patient, who died a few days later. Although the patient presented with septic symptoms and with a heavy growth of gram-negative diplococci in the lymph node, blood cultures remained negative. M. canis is an upper-airway commensal from dogs and cats and is considered nonpathogenic for humans, although this is the third reported human isolate of this species.

Métabolisme de l'acide indolyl-3-acétique dans les cultures de cellules d'Acer pseudoplatanus cultivés in vitro

1977 ◽  
Vol 55 (19) ◽  
pp. 2530-2534 ◽  
Author(s):  
F. Maillard ◽  
J.-P. Zrÿd
Keyword(s):  
Cell Wall ◽  
Acetic Acid ◽  
Culture Medium ◽  
Degradation Products ◽  
Cell Suspensions ◽  
The Other ◽  
Acer Pseudoplatanus ◽  
Kinetics Of

Incubation of cell suspensions of sycamore (Acer pseudoplatanus) with β-indoyl-3-acetic acid (IAA) first led to the formation of IAA-glycosides, then to that of IAA-aspartate. Great differences are observed between the kinetics of IAA transformed by two distinct strains: one, auxin dependent (S), the other, auxin independent (MB). Other degradation products are only found in the culture medium. The localization of IAA-degrading systems in the cell wall is postulated. The auxin requirement of the S strain is discussed.

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