Diferulic acids

Garcia-Conesa, M.T., Wilson, P.D., Plnmb, G.W., Ralph, ., and Williamson, G. Antioxida nt properties of 4,4 -dihydroxy-3,3 -dimethoxy-p,p -bicinnamic acid (8-8-diferulic acid, non-cyclic form), / Sci. Food Agric., 79 379-384, 1999. 

Ferulic acid has often been reported as a model compound for the investigation of bioavailability of phenolic acids, as free or esterified forms (Table 2.3), since it is abundantly present in food. Absorption via the gastrointestinal tract has also been found for dimers of ferulic acid, or diferulic acids, released from cereal brans [Andreasen et al., 2001b]. 

Andreasen MF, Kroon PA, Williamson G, Garcia-Conesa MT. 2001b. Intestinal release and uptake of phenolic antioxidant diferulic acids. Free Radio Biol Med 31 304-314. 

Beet pectin and wheat-flour pentosans undergo an oxidative gelation (Neukom, 1976 Neukom and Markwalder, 1978) instigated by ferulic acid peroxidase through diferulic acid crosslinking. Crowe (1989) and Thibault et al. (1991) effected the same crosslinking with persulfate and chlorine, respectively. 

Yamamoto, H., Hoshino, T, and Uchiyama, T., Convenient preparation and quantification of 5,5 -diferulic acid. Biosci. Biotechnol. Biochem., 63, 390, 1999. 

On its own, DMD is too powerfnl an electrophilic reagent to be considered for lignin-retaining bleaching. Bnt, in carefnl conjunction with alkaline peroxide, it has been found useful in bleaching the ferulic acid-linked lignins in wheat straw mechanical pulps. Pan et al. [112] evaluated DMD for its ability to oxidize ferulic acid (IVa), ferulic acid ethyl ester and diferulic acid (IVb). All these model compounds were completely oxidized at room temperature. 

The characterisation of the crosslinking of the pectic network is still a matter of research. In some plant families, e.g. the Chenopodiaceae, of which the most investigated is the sugar beet (Beta vulgaris L.), the potential for covalent crosslinking through phenolic residues, such as diferulic acid, has been demon-... 

Ferulic acid is dimerized in the plant cell wall by peroxidases to several neolignans. In fact, class III plant peroxidases, such as that purified from barley, are able to oxidize ferulic acid with fa values of 2.9 pM-1 s 1 at pH 3. 96 [34], The main products of ferulic acid dimerization by peroxidase are 5,8 -diferulic acid (XX), 5,5 -diferulic acid (XXI), 8-0-4 -diferulic acid (XXII) and a dihydrobenzofuran dimer /rans-5-[( T)-2-carboxyvinyl]-2-(4-hydroxy-3-methoxyphenyl)-7-methoxy-2,3-dihydrobenzofuran-3-carboxy-lic acid (XXIII) derived from a 5-8 coupling mechanism (Scheme X) [100],... 

MarkwALDER, H. U., and H. Neukom Diferulic acid as a possible cross-link in hemicelluloses from wheat germ. Phytochemistry 15, 836—837 (1976). 

HARTLEY R.D. and JONES E.C. 1976. Diferulic acid as a component of cell /alls of Lolium multiflorum. Phytochemistry, 15, 1157-1160. 

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