The Wall-Bound Phenolics of Chinese Water Chestnut (Eleocharisdulcis)

✍ Scribed by Parr, Adrian J; Waldron, Keith W; Ng, Annie; Parker, Mary L

• Book ID: 102648749
• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 621 KB
• Volume: 71
• Category: Article
• ISSN: 0022-5142
• DOI: 10.1002/(sici)1097-0010(199608)71:4<501::aid-jsfa608>3.0.co;2-l

✦ Synopsis

Chinese water chestnut (CWC) is a vegetable in which the edible storage parenchyma exhibits thermal stability to texture. This property has been attributed to the presence of large quantities of simple phenolics which exhibit pH-dependent autofluorescence. The identities of the major phenolic components were assessed by reverse-phase HPLC after sequentially extracting them with increasing strengths of alkali from purified CWC cell wall material. The levels of cold-alkali-liberated phenolics were very high (12.2 mg g-' cell wall material).

Ferulic acid dominated the monomeric phenol fraction (7.2 mg g-'), although small quantities of aldehydes were also released. A number of different diferulic acids were also identified, of which the 8-0-4-linked form was the major component (2.8 mg g-' ), with 8,S-diferulic acid and the familiar 5,5'-form also present in smaller quantities (910 and 988 pg g-', respectively). Hence, approximately 40% of the ferulic acid in the wall was present as dimers which are potentially available to form extensive, heat-resistant cross-links between polysaccharides within the wall, and between cells.