Wheat bran phenols

Triticum vulgere Wheat bran phenol 5-nonadecylresorcinol N.W. Australia... 

Phenolic Acid or Aldehyde (mg g 1 cell walls) Maize Stem(6) Barley Stem(6) Wheat Bran(6) Italian Ryegrass Shoot(7)... 

Phenolic acids, and especially ferulic acid, which is abundantly present in cereals, is found esterified to the polysaccharides present in primary and secondary cell walls of plants. Ferulic acid is the major phenolic acid occurring in the cell walls of monocotyledons and appears as cis and the more abundant trans isomers (reviewed in [Klepacka and Forna, 2006]). Ferulic acid is found in wheat, maize, rye, barley [Sun et al., 2001], oats, spinach, sugar beet, and water chesnuts [Clifford, 1999], generally esterified, and rarely as free form, such as in barley [Yu et al., 2001]. It is esterified in primary cell walls to arabinoxylans (Fig. 2.4) in the aleurone layer and pericarp [Clifford, 1999], as in spinach [Fry, 1982] or in wheat bran [Smith and Hartley, 1983], Ferulic acid can also be found esterified to other hydroxycinnamic acids such as in Mongolian medicinal plants where it is found as feruloylpodospermic acid, which is... 

Esterases. Acetyl esterase (EC 3.1.1.6) removes acetyl esters from acetylated xylose and short-chain xylo-oligomers. It s polymeracting counterpart, acetyl xylan esterase (EC 3.1.1.72), has a similar activity, but prefers polymeric xylan.244 In addition to acetate-specific enzyme detection kits, HPLC or GC analysis of acetate release from native extracted xylan and chemically acetylated xylan, colorimetric substrates, such as p-nitrophenol acetate and /3-napthyl acetate, or the fluorometric substrate, 4-methylumbelliferyl acetate are also used to assay acetyl esterases.244,253 The third esterase, ferulic acid esterase (EC 3.1.1.73), hydrolyzes the ester bond between ferulic acid or coumaric acid and the arabinose side chain of arabinoxylan. Assays for this activity are usually carried out using starch-free wheat bran or cellulase-treated gramineous biomass as a substrate and monitoring ferulic or coumaric acid released by HPLC or TLC. When preparing enzyme-treated substrates, care must be taken to employ phenolic-acid-esterase-free cellulases.244 Other substrates include methyl and ethyl esters of the phenolic acids, as well as finely ground plant biomass.240,254,255... 

Kim, K. Tsao, R. Yang, R. Cui, S.W. 2006. Phenolic acid profiles and antioxidant activities of wheat bran extracts and the effect of hydrolysis conditions. Food Chem. 95 466 73. 

Zhou, K. Yin, J. Yu, L. 2005. Phenolic acid, tocopherol and carotenoid compositions, and antioxidant functions of hard red winter wheat bran. J. Agric. Food Chem. 53 3916-3922. 

Phenol/aceticth acid/water. PAW desorbs residual intracellular proteins, some starch, adsorbed deoxycholate, lipids, and pigments from the SDC-residue. The amount of cell wall polysaccharides solubilized is approximately 1% of the dry weight of the purified CWM for potatoes, runner beans, wheat bran, and oats. 

Jing W, Baoguo S, Yanping C, Yuan T, Xuehong L (2008) Optimisation of ultrasound-assisted extraction of phenolic compounds from wheat bran. Food Chem 106 804—810... 

In contrast to the previous examples, oxidative treatments may promote positive consequences in some other cases, as they decrease concentrations in phenolic acids (and other phenolics) and limit subsequent oxidations. Therefore, hyperoxidation of musts during wine processing has sometimes been proposed, and this process particularly affected HCA derivatives [27]. In addition, a peroxidasic treatment allowed the dimerization of ferulic acid in wheat bran tissues and consequently decreased arabinoxylan solubility and increased mechanical strength of the tissue [58]. 

The wheat bran, rich in dietmy fiber, is one of the most popular sources of feed-stuffs for ruminants (Chapter 18). Some of the wheat bran is used to produce whole wheat flour or ground to produce meals with different granulations. These products me used to produce high-fiber bakery products such as breads, cookies, and breakfast foods. Wheat bran is a rich somce of insoluble dietmy fiber and important antioxidants and phenolic compounds such as ferulic acid. Unfortunately, wheat bran contains negligible amounts of soluble dietmy fiber (Chapter 17). 

Matus-Cadiz MA, Daskalchuk TE, Verma B, Puttick D, Chibbar RN, Gray GR, Perron CE, Tyler RT and Hucl P. 2008. Phenolic compounds contribute to dark bran pigmentation in hard white wheat. J Agric Food Chem 56(5)1644-1653. 

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