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Figure 7. Correlation between the degradation of Cyd-3-glc and the
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ture, pH, and chemical composition (25-27): for example,
2
21, 472–478.
(
(
(
(
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´
2þ
3þ
the release of Fe /Fe from stainless steel electrodes (25, 28),
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hydrogen peroxide caused by a lower pH value of sample
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D
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4
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0
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benzofuran and protocatechuic acid. According to Hrazdina and
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2
at the 2-carbon of the molecule, the heterocyclic ring was cleaved
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´
2
3
of the malvone type. These esters were further hydrolyzed under
alkaline conditions to the B-ring acid, the sugar substituent of the
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3-position, and the elusive 2,4,6-trihydroxyphenylacetic acid (8).
(
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e
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