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PH Stability and Antioxidant Power of CycloDOPA and Its Derivatives.

ABSTRACT: CycloDOPA (leukodopachrome), a well known metabolite of tyrosine, is a precursor of melanine in mammalian organisms and of the pigment betalain in plants. However, the isolation of cycloDOPA from natural sources has not been widely reported. In the present work, the stabilities of cycloDOPA and cycloDOPA methyl ester at various pH levels were studied. Both compounds were stable under acidic conditions. By contrast, both compounds were unstable when the pH was shifted from neutral to basic to form indole derivatives as major products. Based on the pH stability, cycloDOPA and its derivatives were subjected to the DPPH radical scavenging assay for the first time.

SUBMITTER: Nakagawa S

PROVIDER: S-EPMC6222597 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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pH Stability and Antioxidant Power of CycloDOPA and Its Derivatives.

Nakagawa Shiori S Tachrim Zetryana Puteri ZP Kurokawa Natsumi N Ohashi Fumina F Sakihama Yasuko Y Suzuki Takeyuki T Hashidoko Yasuyuki Y Hashimoto Makoto M

Molecules (Basel, Switzerland) 20180803 8

CycloDOPA (leukodopachrome), a well known metabolite of tyrosine, is a precursor of melanine in mammalian organisms and of the pigment betalain in plants. However, the isolation of cycloDOPA from natural sources has not been widely reported. In the present work, the stabilities of cycloDOPA and cycloDOPA methyl ester at various pH levels were studied. Both compounds were stable under acidic conditions. By contrast, both compounds were unstable when the pH was shifted from neutral to basic to for ...[more]

PMID: 30081515

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