Degradation of benzoic acid and

Wolterink AFWM, E Schiltz, P-L Hagedoorn, WR Hagen, SWM Kengen, AIM Stams (2003) Characterization of the chlorate reductase from Pseudomonas chloritidismutans. J Bacterial 185 3210-3213. Ziegler K, K Braun, A Bdckler, G Fuchs (1987) Studies on the anaerobic degradation of benzoic acid and 2-aminobenzoic acid by a denitrifying Pseudomonas strain. Arch Microbiol 149 62-69. 

Elder DJ, Kelly DJ. The bacterial degradation of benzoic acid and benzenoid compounds under anaerobic conditions unifying trends and new perspectives. FEMS Microbiol Rev 1994 13(4) 441-468. 

The Sensitizing Effect of N20 on X-ray Induced Degradation of Benzoic Acid and Anthranilic Acid... 

Biological. Benzoic acid may degrade to catechol if it is the central metabolite whereas, if protocatechuic acid (3,4-dihydroxybenzoic acid) is the central metabolite, the precursor is 3-hydroxybenzoic acid (Chapman, 1972). Other compounds identified following degradation of benzoic acid to catechol include cis,c/5-muconic acid, (+)-muconolactone, 3-oxoadipate enol lactone, and 3-oxoadipate (quoted, Verschueren, 1983). Pure microbial cultures hydroxylated benzoic acid to 3,4-dihydroxybenzoic acid, 2- and 4-hydroxybenzoic acid (Smith and Rosazza, 1974). In activated sludge, 65.5% mineralized to carbon dioxide after 5 d (Freitag et al., 1985). 

The photoreactivity results showed that the reactor reaches steady state conditions after a long period of time (ca. 70 h) from the beginning of the irradiation. At steady state conditions the main photooxidation product was benzaldehyde but also benzyl alcohol and traces of benzoic acid and phenol were detected at all the experimental conditions used. During the transient period, benzene together with CO2 were also produced. No significant evidence of CO2 production was observed at steady state conditions. These results obviously indicate that at the experimental conditions used the photoprocess does not give rise to a complete degradation of toluene. 

Aromatic compounds can also be degraded anaerobically, via reductive pathways, which have been reviewed. The best-characterized example is the degradation of benzoic acid in Rhodopseudomonas palustris and Thauera aromatica via the pathway shown in Figure 8. Benzoyl-CoA is formed, and then a reductase enzyme is able to reduce the aromatic ring to a cyclohexadiene. Following two consecutive additions of water, and oxidation to a /3-keto ester, hydrolytic cleavage gives a linear 7-carbon CoA thioester, which can then be broken down via fatty acid /3-oxidation. 

In the present paper radiation chemical studies are presented on the x-ray induced degradation of anthranilic acid and hydroxylation of benzoic acid. The effect of the electron scavenger N20 is compared with that of NO3", H0O0, and 02. The results suggest that N20" (or N2OH) radicals do not spontaneously give rise to OH radicals in solutions of benzoic acid or anthranilic acid. 

Thus, the sensitizing effect of N20 on x-ray induced degradation of benzoic acid, anthranilic acid and p-aminobenzoic acid (34) gives no evidence for a conversion of hydrated electrons into OH radicals by N20. 

Effects of 02, N20, and H202. The finding that the G-value for degradation of benzoic acid in Oo is 2.45 (27), whereas dimers are found in extremely small yields, may be explained if nearly all intermediate benzoic acid radicals interact with 02 according to Equations 12 or 13. 

The effect of N20 on x-ray induced hydroxy la tion and degradation of benzoic acid could be explained by suppression of Reaction 10 and thus of Reaction 14 ... 

Oil-soluble resin is not as popular as it once was but still has occasional application. Oil-soluble resin application is limited because its melting point is more than 300°F. Therefore, removal must be entirely from dissolution in produced oil. If that is not accomplished, a separate solvent treatment must be pumped to remove the diverter. Therefore, other degradable diverters, such as forms of benzoic acid and wax beads, are preferable because of their lower melting points (see table 6-9). 

In general,. alkoxy- or silyloxy-isoxazolidines when treated with acid produce 2-isoxazo-lines <77AHC(2i)207, 74MIP41601). Other isoxazolidines are cleaved at the N—O bond with further degradation then following <77AHC(2i)207). The treatment of (182) with HCl generated cinnamic acid and a small amount of benzoic acid, whereas treatment of (182) with... 

Hickey WJ, DD Focht (1990) Degradation of mono-, di-, and trihalogenated benzoic acids by Pseudomonas aeruginosa JB2. Appl Environ Microbiol 56 3842-3850. 

Phenolic acids can be allelopathic but their presence in soil is ephemeral due to rapid degradation and/or sorption by soil particles (Inderjit 2004). Sorption of benzoic acid onto soil particles increased with concentration and it may explain the reason for the limited allelopathic effect of benzoic acid at concentrations often recorded in natural soil (Inderjit 2004). Microorganisms help to generate allelochemicals, but they may also modify toxic compounds into nontoxic compounds (Khanh et al. 2005). Allelochemicals are changed in composition and quantity during the residue decomposition. Allelopathy plays an important function in nutrient recycling (Rice 1984). 

Benzoic acid, a common food preservative, may be a suitable substrate to achieve biostimulation. It is a relatively inexpensive, harmless aromatic compound that has been previously used in analogue enrichment1 schemes to enhance biodegradation of the aromatic herbicide, 2,3,6-trichlorobenzoic acid (2,3,6-TBA) [336]. Benzoate ion is also an intermediate in the toluene pathway and it can induce related enzymes involved in the degradation of toluene and m-and p-xylenes [336]. In addition, the anionic nature of benzoic acid would minimize its retardation and facilitate its distribution when injected into an... 

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