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Antioxidative polyphenols from walnuts (Juglans regia L.).

Toshiyuki Fukuda·Hideyuki Ito·Takashi Yoshida
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Abstract

Three hydrolyzable tannins, glansrins A-C, together with adenosine, adenine, and 13 known tannins were isolated from the n-BuOH extract of walnuts (the seeds of Juglans regia L.). Glansrins A-C were characterized as ellagitannins with a tergalloyl group, or related polyphenolic acyl group, based on spectral and chemical evidence. The 14 walnut polyphenols had superoxide dismutase (SOD)-like activity with EC(50) 21.4-190 microM and a remarkable radical scavenging effect against 1,1-diphenyl-2-picrylhydrazyl (DPPH) (EC(50) 0.34-4.72 microM).

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Biphenyl CompoundsFlavonoidsFree Radical ScavengersHydrazinesJuglansMagnetic Resonance SpectroscopyMolecular StructurePhenolsPicratesPolyphenolsSeedsSuperoxide DismutaseJournal Article

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Toshiyuki Fukuda, Hideyuki Ito, Takashi Yoshida. 2003. Antioxidative polyphenols from walnuts (Juglans regia L.).. https://doi.org/10.1016/s0031-9422(03)00333-9

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