Potential for carboxylation–dehydroxylation of phenolic compounds by a methanogenic consortium

1993 ◽  
Vol 39 (7) ◽  
pp. 642-648 ◽  
Author(s):  
Jean-Guy Bisaillon ◽  
François Lépine ◽  
Réjean Beaudet ◽  
Michel Sylvestre

An anaerobic consortium that carboxylated and dehydroxylated phenol to benzoate, and 2-cresol to 3-methylbenzoic acid, under methanogenic conditions was studied. Phenol induced this transformation activity. Addition of 4-hydroxypyridine or an increase in the concentration of proteose peptone to 0.5% (w/v) delayed the transformation. Phenol enhanced the rate of transformation of 2-cresol whereas 2-cresol delayed the transformation of phenol. Phenols with ortho-substitutions (chloro-, fluoro-, bromo-, hydroxyl-, amino-, or carboxyl-) were transformed to meta-substituted benzoic acids. However, meta- and para-substituted phenols (cresols, fluorophenols, and chlorophenols) were not transformed. Phenol was most rapidly metabolized, followed by catechol, 2-cresol, 2-fluorophenol, 2-aminophenol, 2-chlorophenol, 2-hydroxybenzoic acid, and 2-bromophenol. The consortium O-demethylated anisole to phenol and 2-methoxyphenol to catechol, and oxidized 2-hydroxybenzyl alcohol to 2-hydroxybenzoic acid. Aniline, 2-ethylphenol, 2-hydroxypyridine, 2-acetamidophenol, 2,6-dimethylphenol, 2-phenylphenol, and 1-naphthol were not metabolized.Key words: phenolic compounds, methanogenic consortium, carboxylation–dehydroxylation.

1999 ◽  
Vol 45 (3) ◽  
pp. 235-241 ◽  
Author(s):  
A Charest ◽  
J -G Bisaillon ◽  
F Lépine ◽  
R Beaudet

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.


1995 ◽  
Vol 41 (3) ◽  
pp. 266-272 ◽  
Author(s):  
L. Létouraeau ◽  
J.-G. Bisaillon ◽  
F. Lépine ◽  
R. Beaudet

A methanogenic consortium transforming phenol to benzoic acid was submitted to different treatments to characterize the carboxylating microorganisms and eventually to facilitate their isolation. Under aerobic conditions, phenol was not transformed by the consortium and no growth was observed on solid medium. The consortium from an inoculum that was treated with heat, or heat and ethanol, retained the ability to carboxylate phenol under strictly anaerobic conditions. Electron microscopic observations of the consortium from an inoculum that was heated for 15 min at 80 °C revealed only Gram-positive bacilli. In this culture, methane production was not detected and benzoic acid accumulated. Five colonies with distinct morphologies were isolated from this culture on solid medium. Four of these strains were identified as Clostridium spp. In contrast to the untreated culture, none of the strains isolated were able to carboxylate phenol in pure culture or in coculture, nor could they decarboxylate or dehydroxylate 4-hydroxybenzoic acid, or oxidize 2-hydroxybenzyl alcohol, or O-demethylate anisole or 2-methoxyphenol. Also, the consortium from a treated inoculum retained its ability to decarboxylate and dehydroxylate 4-hydroxybenzoic acid forming phenol and benzoic acid, respectively, but could not accomplish the other reactions. These results suggest that spore-forming microorganisms are involved in the carboxylation of phenol and in the decarboxylation and dehydroxylation of 4-hydroxybenzoic acid.Key words: spore-forming bacteria, phenol, benzoic acid, methanogenic conditions, carboxylation.


1994 ◽  
Vol 29 (1) ◽  
pp. 117-128 ◽  
Author(s):  
J.-G. Bisaillon ◽  
R. Beaudet ◽  
F. Lépine ◽  
M. Sylvestre

Abstract An anaerobic consortium was isolated for its ability to degrade phenolic compounds under methanogenic conditions. The addition of proteose peptone to the minimal salt medium was necessary in order to maintain its activity. The consortium was shown to degrade phenol via its carboxylation to benzoate. Potential intermediates of benzoate degradation given as substrates to the consortium suggest that benzoate is transformed to 1-cyclohexene carboxylate and to heptanoate. The carboxylating activity of the consortium is not restricted to phenol but efficiently transforms the ortho but not the meta and para isomers of cresol, fluorophenol and chlorophenol. The carboxylation occurs at the para position relative to the phenolic hydroxyl group. The consortium is composed of seven different morphological forms. Phenol carboxylating microorganisms were evaluated at 1 × l08 − 8 × l09 cells/ml. These microorganisms are probably nonsyntrophic since inhibition of methanogenesis and the presence of hydrogen in the gaseous phase did not prevent the carboxylation of phenol. The carboxylating microorganisms have not yet been isolated but an active consortium containing only five morphological forms has been obtained.


1967 ◽  
Vol 45 (5) ◽  
pp. 585-593 ◽  
Author(s):  
Bruce A. Bohm ◽  
Rolla M. Tryon

Forty-six ferns, representing 28 genera and 8 families, were examined for hydroxylated cinnamic acids and benzoic acids. In most plants examined the "basic complement" of cinnamic acids, p-coumaric, caffeic, and ferulic, was present. In these plants p-hydroxybenzoic acid, protocatechuic acid, and vanillic acid were generally also present. Of much more limited distribution were sinapic acid, syringic acid, and o-coumaric acid. Coumarin was shown to be present in Dennstaedtia punctilobula, the only fern tested which possessed this type of compound. The data available from three ferns reported in the literature are also included in this survey; one represents an additional family and one represents an additional genus.An experiment with DL-phenylalanine-1-14C and DL-phenylalanine-3-14C and Cyathea arborea showed the incorporation of label into p-coumaric acid, caffeic acid, and ferulic acid.


1994 ◽  
Vol 59 (9) ◽  
pp. 2029-2041
Author(s):  
Oldřich Pytela ◽  
Taťjana Nevěčná

The kinetics of decomposition of 1,3-bis(4-methylphenyl)triazene catalyzed with 13 substituted benzoic acids of various concentrations have been measured in 25 vol.% aqueous methanol at 25.0 °C. The rate constants observed (297 data) have be used as values of independent variable in a series of models of the catalyzed decomposition. For the catalytic particles were considered the undissociated acid, its conjugated base, and the proton in both the specific and general catalyses. Some models presumed formation of reactive or nonreactive complexes of the individual reactants. The substituent effect is described by the Hammett equation. The statistically best model in which the observed rate constant is a superposition of a term describing the dependence on proton concentration and a term describing the dependence on the product of concentrations of proton and conjugated base is valid with the presumption of complete proton transfer from the catalyst acid to substrate, which has been proved. The behaviour of 4-dimethylamino, 4-amino, and 3-amino derivatives is anomalous (lower catalytic activity as compared with benzoic acid). This supports the presumed participation of conjugated base in the title process.


2009 ◽  
Vol 74 (1) ◽  
pp. 29-42 ◽  
Author(s):  
Vilve Nummert ◽  
Mare Piirsalu ◽  
Signe Vahur ◽  
Oksana Travnikova ◽  
Ilmar A. Koppel

The second-order rate constants k (in dm3 mol–1 s–1) for alkaline hydrolysis of phenyl esters of meta-, para- and ortho-substituted benzoic acids, X-C6H4CO2C6H5, have been measured spectrophotometrically in aqueous 0.5 and 2.25 M Bu4NBr at 25 °C. The substituent effects for para and meta derivatives were described using the Hammett relationship. For the ortho derivatives the Charton equation was used. For ortho-substituted esters two steric scales were involved: the EsB and the Charton steric (υ) constants. When going from pure water to aqueous 0.5 and 2.25 M Bu4NBr, the meta and para polar effects, the ortho inductive and resonance effects in alkaline hydrolysis of phenyl esters of substituted benzoic acids, became stronger nearly to the same extent as found for alkaline hydrolysis of C6H5CO2C6H4-X. The steric term of ortho-substituted esters was almost independent of the media considered. The rate constants of alkaline hydrolysis of ortho-, meta- and para-substituted phenyl benzoates (X-C6H4CO2C6H5, C6H5CO2C6H4-X) and alkyl benzoates, C6H5CO2R, in water, 0.5 and 2.25 M Bu4NBr were correlated with the corresponding IR stretching frequencies of carbonyl group, (ΔνCO)X.


Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1810
Author(s):  
Monika Kędzierska-Matysek ◽  
Małgorzata Stryjecka ◽  
Anna Teter ◽  
Piotr Skałecki ◽  
Piotr Domaradzki ◽  
...  

The study compared the content of eight phenolic acids and four flavonoids and the antioxidant activity of six Polish varietal honeys. An attempt was also made to determine the correlations between the antioxidant parameters of the honeys and their polyphenol profile using principal component analysis. Total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity (ABTS) and reduction capacity (FRAP) were determined spectrophotometrically, and the phenolic compounds were determined using high-performance liquid chromatography (HPLC). The buckwheat honeys showed the strongest antioxidant activity, most likely because they had the highest concentrations of total phenols, total flavonoids, p-hydroxybenzoic acid, caffeic acid, p-coumaric acid, vanillic acid and chrysin. The principal component analysis (PCA) of the data showed significant relationships between the botanic origin of the honey, the total content of phenolic compounds and flavonoids and the antioxidant activity of the six Polish varietal honeys. The strongest, significant correlations were shown for parameters of antioxidant activity and TPC, TFC, p-hydroxybenzoic acid, caffeic acid and p-coumaric acid. Analysis of four principal components (explaining 86.9% of the total variance), as a classification tool, confirmed the distinctiveness of the Polish honeys in terms of their antioxidant activity and content of phenolic compounds.


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