The Role of Hydrogen Peroxide in Dioxygen Induced Hydroxylation of Salicylic Acid

Lang, Kamil; Wagnerová, D. M.; Brodilová, Jiřina

doi:10.1135/cccc19942447

Cited by 8 publications

(4 citation statements)

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“…These results are consistent with Lang et al (1996) who stated, "the effect ofpH on formation ofhydroxylation products is more profoundfor 2,5-DHB than for 2,3-DHB." The change in isomer ratio, [2,3-DHBA]:[2,5-DHBAJ, and absolute yield with pH is also consistent with trends observed by Jen et al (1998) and Lang et al (1994Lang et al ( , 1996 although a direct comparison is not possible due to differences in experimental conditions. The close correlation between 2,5-DHBA yield and the salicylate anion supports the theory that hydroxylation occurs via a hydroxycyclohexadienyl radical intermediate.…”

Section: Linear Response To Gas Phase Ohsupporting

confidence: 66%

Evaluation of the Salicylic Acid–Liquid Phase Scrubbing Technique to Monitor Atmospheric Hydroxyl Radicals

Salmon

Schiller

Harris

2004

Journal of Atmospheric Chemistry

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Abstract. A novel method has been examined for monitoring tropospheric hydroxyl radicals (OH), the most important oxidant in tropospheric chemistry. Aqueous phase salicylic acid reacts with atmospheric OH to produce 2,5-dihydroxy benzoic acid (2,5-DHBA) and other products. High Performance Liquid Chromatography (HPLC) is used to separate the post-reaction solution and the products are quantified using fluorescence detection. Unlike other methods, it has been reported to be inexpensive, portable and relatively simple. Although the sensitivity was sufficient to measure typical daytime OH concentrations of 0.04--0.4 ppt., the method was hindered by numerous interferences. Successive identification and elimination of these still resulted in a signal that was much larger than expected. Tests showed that this was not likely to be due to ozone, H0 2 , NOx, H 2 0 2 , aerosols, light or bacteria. Experimental and numerical studies suggest that the interference could be due to methyl peroxy radicals. The effect of many other components in the atmosphere, both individual and combined, must also be tested before the method can be used reliably in the field. The validity of previous reports of ambient hydroxyl measurements using this technique is therefore brought into question.

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Section: Linear Response To Gas Phase Ohsupporting

confidence: 66%

Evaluation of the Salicylic Acid–Liquid Phase Scrubbing Technique to Monitor Atmospheric Hydroxyl Radicals

Salmon

Schiller

Harris

2004

Journal of Atmospheric Chemistry

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“…Mason et al (1957) On the other hand, Groves et al (1974;1976) have used this mechanism to describe the hydroxylation of cyclohexanol, which is strongly supported by the formation of stereoselective hydroxylation products. These interactions have also been observed by Lunak et al (1994) and Lang et al (1994) during the photochemical hydroxylation of 2-HBA, where the formation of 2,3-DHBA was favored. In the Fenton reaction, the attack of • OH occurs because of its extremely high radical activity.…”

Section: +supporting

confidence: 77%

Degradation of 2-hydroxybenzoic acid by advanced oxidation processes

Zanta

Martínez‐Huitle

2009

Braz. J. Chem. Eng.

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-In this study, advanced oxidation processes (AOPs) such as the UV/H 2 O 2 and Fenton processes were investigated for the degradation of 2-hydroxybenzoic acid (2-HBA) in lab-scale experiments. Different [H 2 O 2 ]/[2-HBA] molar ratios and pH values were used in order to establish the most favorable experimental conditions for the Fenton process. For comparison purposes, degradation of 2-HBA was carried out by the UV/H 2 O 2 process under Fenton experimental conditions. The study showed that the Fenton process (a mixture of hydrogen peroxide and Fe 2+ ion) was the most effective under acidic conditions, leading to the highest rate of 2-hydroxybenzoic acid degradation in a very short time interval. This same process led to a six-fold acceleration of the oxidation rate compared with the UV/H 2 O 2 process. The degradation of 2-hydroxybenzoic acid was found to follow first-order kinetics and to be influenced by the type of process and the experimental conditions. The experimental results showed that the most favorable conditions for 2-HBA degradation by the

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“…The 2,3-DHBA/2,5-DHBA ratio has often been used as a measure of hROS, but the ratio of these two varies dependent on the chemical environment and thus a reliable quantification cannot be performed using this approach [see 28]. In vitro work also demonstrated that even in a simple Fenton system the ratio showed a time dependence, which again raised doubt on its reliability [28, [101][102][103]. Furthermore, salicylic acid may directly perturb the responses to hROS as it has been shown to affect inflammatory responses [104][105][106][107].…”

Section: Salicylate (Sa)mentioning

confidence: 99%

Highly reactive oxygen species: detection, formation, and possible functions

Freinbichler

Colivicchi

Stefanini

et al. 2011

Cell. Mol. Life Sci.

141

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The so-called reactive oxygen species (ROS) are defined as oxygen-containing species that are more reactive than O(2) itself, which include hydrogen peroxide and superoxide. Although these are quite stable, they may be converted in the presence of transition metal ions, such as Fe(II), to the highly reactive oxygen species (hROS). hROS may exist as free hydroxyl radicals (HO·), as bound ("crypto") radicals or as Fe(IV)-oxo (ferryl) species and the somewhat less reactive, non-radical species, singlet oxygen. This review outlines the processes by which hROS may be formed, their damaging potential, and the evidence that they might have signaling functions. Since our understanding of the formation and actions of hROS depends on reliable procedures for their detection, particular attention is given to procedures for hROS detection and quantitation and their applicability to in vivo studies.

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The Role of Hydrogen Peroxide in Dioxygen Induced Hydroxylation of Salicylic Acid

Cited by 8 publications

References 0 publications

Evaluation of the Salicylic Acid–Liquid Phase Scrubbing Technique to Monitor Atmospheric Hydroxyl Radicals

Evaluation of the Salicylic Acid–Liquid Phase Scrubbing Technique to Monitor Atmospheric Hydroxyl Radicals

Degradation of 2-hydroxybenzoic acid by advanced oxidation processes

Highly reactive oxygen species: detection, formation, and possible functions

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