Hydroxyl Free Radical-Mediated Oxidative Degradation of Quercetin and Morin: A Preliminary Investigation

Makris, Dimitris P.; Rossiter, John T.

doi:10.1006/jfca.2001.1030

Cited by 83 publications

(61 citation statements)

References 23 publications

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“…The same products were isolated in the result of quercetin oxidation by hydrogen peroxide under the same pH conditions. The formation of the aforementioned products is in complete agreement with literature data on the oxidation of quercetin under different conditions [14][15][16][17][18][19][20][21][22][23][24][25][26][27]. To date the oxidative decarbonylation of 1 was considered the likely process which could take place preferably in non-aqueous solvents in the presence of strong bases and often at above-ambient temperatures (in pyridine during 14 h [14], in dimethylformamide with additives of potassium tert-butoxide at 37 °C during 3 h [16], etc.).…”

Section: Analysis Of Oxidation Productssupporting

confidence: 87%

“…Similar processes of oxidative destruction of 3-hydroxyflavones (including quercetin) by air oxygen with the formation of the same products were observed under catalysis by the enzymes quercetinase [16] and tyrosinase [17], in the presence of radical initiators like azodiisobutyronitrile [18][19][20] or the CuSO 4 /H 2 O 2 system [21], and in the complexes of flavonols with Cu 2+ ions [22,23]. The same degradation products were detected as a result of γ-irradiation of quercetin solutions [24,25] and even heating of its solutions at the presence of oxygen [26,27].…”

Section: Introductionmentioning

confidence: 54%

“…This allows us to classify 1 as more unstable than the well-known ascorbic acid, which is inert to contact with air under the same conditions. Of course, there is a high probability that the products of this reaction should be the same as established previously [14][15][16][17][18][19][20][21][22][23][24][25][26][27], but this should be confirmed independently. In addition there is the problem is the origin of gaseous products formed in this reaction (CO or CO 2 ), because the oxidative state of carbon in these oxides determines the possible mechanism of the process.…”

Section: Introductionmentioning

confidence: 56%

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Identification of the Products of Oxidation of Quercetin by Air Oxygenat Ambient Temperature

Зенкевич

Eshchenko²,

Makarova³

et al. 2007

Molecules

136

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Oxidation of quercetin by air oxygen takes place in water and aqueous ethanol solutions under mild conditions, namely in moderately-basic media (pH ∼ 8-10) at ambient temperature and in the absence of any radical initiators, without enzymatic catalysis or irradiation of the reaction media by light. The principal reaction products are typical of other oxidative degradation processes of quercetin, namely 3,4-dihydroxy-benzoic (protocatechuic) and 2,4,6-trihydroxybenzoic (phloroglucinic) acids, as well as the decarboxylation product of the latter -1,3,5-trihydroxybenzene (phloroglucinol). In accordance with the literature data, this process involves the cleavage of the γ-pyrone fragment (ring C) of the quercetin molecule by oxygen, with primary formation of 4,6-dihydroxy-2-(3,4-dihydroxybenzoyloxy)benzoic acid (depside). However under such mild conditions the accepted mechanism of this reaction (oxidative decarbonylation with formation of carbon monoxide, CO) should be reconsidered as preferably an oxidative decarboxylation with formation of carbon dioxide, CO 2 . Direct head-space analysis of the gaseous components formed during quercetin oxidation in aqueous solution at ambient temperature indicates that the ratio of carbon dioxide/carbon monoxide in the gas phase after acidification of the reaction media is ca. 96:4 %. Oxidation under these mild conditi- Molecules, 2007, 12 655ons is typical for other flavonols having OH groups at C 3 (e.g., kaempferol), but it is completely suppressed if this hydroxyl group is substituted by a glycoside fragment (as in rutin), or a methyl substituent. An alternative oxidation mechanism involving the direct cleavage of the C 2 -C 3 bond in the diketo-tautomer of quercetin is proposed.

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Section: Analysis Of Oxidation Productssupporting

confidence: 87%

Section: Introductionmentioning

confidence: 54%

Section: Introductionmentioning

confidence: 56%

See 1 more Smart Citation

Identification of the Products of Oxidation of Quercetin by Air Oxygenat Ambient Temperature

Зенкевич

Eshchenko²,

Makarova³

et al. 2007

Molecules

136

View full text Add to dashboard Cite

show abstract

“…The interactions of atmospheric plasma reactive species with secondary plant metabolites in lamb's lettuce by Grzegorzewski et al (2011) suggested that OH, O and O2 species may lead to the erosion of the epidermal layer of lettuce where flavonoids and other compounds accumulated in the central vacuoles of guard cells and epidermal cells are released and degraded. Moreover, the reduction in TPC and TFC at higher treatment times might be due to reactive species which were scavenged by phenolic compounds in the blueberries and also cleavage of the central heterocycle in the polyphenolic skeleton and oligomerization (Makris & Rossiter, 2002).…”

Section: Physical Quality Parametersmentioning

confidence: 99%

Atmospheric cold plasma dissipation efficiency of agrochemicals on blueberries

Sarangapani¹,

O'Toole²,

Cullen

et al. 2017

Innovative Food Science & Emerging Technologies

231

120

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“…The accumulation of resorcinol and some of its derivatives is considered to be a defensive response of the plants against bacterial infection [40,41]. In addition, resorcinol could be a degradation product of flavonoids such as quercetin and morin [42].…”

Section: Resorcinolsmentioning

confidence: 99%

Total antioxidant capacity and content of flavonoids and other phenolic compounds in canihua (Chenopodium pallidicaule): An Andean pseudocereal

Peñarrieta

Alvarado

Åkesson

et al. 2008

Molecular Nutrition Food Res

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Total antioxidant capacity (TAC), total phenolic compounds (TPH), total flavonoids (TF) and individual phenolic compounds were determined in canihua collected at approx. 3850 m altitude. The TAC values varied among samples from 2.7 to 44.7 by the ferric reducing antioxidant power (FRAP) method and from 1.8 to 41 by the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) method expressed as micromol of Trolox equivalents/g dw. The content of TPH was 12.4-71.2 micromol gallic acid equivalents/g dw and that of the TF ranged between 2.2 and 11.4 micromol of catechin equivalents/g dw. The data obtained by the four methods showed several significant correlations. Prior to analysis by HPLC, the samples were subjected to acid hydrolysis and in the water-soluble extracts this led to an up to 20-fold increase in the TAC values in comparison with the values of the nonhydrolysed samples. HPLC analysis showed the presence of eight major compounds identified as catechin gallate, catechin, vanillic acid, kaempferol, ferulic acid, quercetin, resorcinol and 4-methylresorcinol. Their estimated contribution to the TAC value (FRAP method) indicated that resorcinols contributed most of the antioxidant capacity of the water-soluble extract. The results show that canihua is a potential source of natural antioxidant compounds and other bioactive compounds which can be important for human health.

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Hydroxyl Free Radical-Mediated Oxidative Degradation of Quercetin and Morin: A Preliminary Investigation

Cited by 83 publications

References 23 publications

Identification of the Products of Oxidation of Quercetin by Air Oxygenat Ambient Temperature

Identification of the Products of Oxidation of Quercetin by Air Oxygenat Ambient Temperature

Atmospheric cold plasma dissipation efficiency of agrochemicals on blueberries

Total antioxidant capacity and content of flavonoids and other phenolic compounds in canihua (Chenopodium pallidicaule): An Andean pseudocereal

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