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Extraction of Lignin with High β-O-4 Content by Mild Ethanol Extraction and Its Effect on the Depolymerization Yield
Published on: January 7, 2019
Two novel dicarboxylic Acid derivatives and a new dimeric hydrolyzable tannin from walnuts
Hideyuki Ito1, Takahiro Okuda, Toshiyuki Fukuda
1Department of Pharmacognosy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Tsushima, Okayama 700-8530, Japan. hito@cc.okayama-u.ac.jp
Abstract:
In addition to the 16 previously reported polyphenols including 3 new ellagitannins, 2 novel dicarboxylic acid derivatives, glansreginins A (1) and B (2), and a new dimeric hydrolyzable tannin, glansrin D (3), were isolated, together with 15 known compounds from walnuts, the seeds of Juglans regia. The structures of the new compounds were elucidated on the basis of 1D- and 2D-NMR analyses and chemical data. The antioxidant effect of these isolates was also evaluated by SOD-like and DPPH radical scavenging activities.
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