Of matairesinol

For example, yatein and podophyllotoxin are biosynthesized from matairesinol (Fig. 12.4) [11, 13, 49]. This conversion involves 5-hydroxylation of one of the 3-methoxy-4-hydroxylphenyl (guaiacyl) moieties of matairesinol to give rise to 5-hydroxymatairesinol (thujaplicatin) followed by dual methylation at the 4- and 5-hydroxyls, giving rise to a 3,4,5-trialkoxyphenyl moiety (Fig. 12.4) [11, 13,49],... 

Umezawa T, Davin LB, Lewis NG (1991) Formation of lignans (-)-secoisolariciresinol and (-)-matairesinol with Forsythia intermedia ceU-free extracts. J Biol Chem 266 10210-10217 Okunishi T, Sakakibara N, Suzuki S et al (2004) Stereochemistry of matairesinol formation by Daphne secoisolariciresinol dehydrogenase. J Wood Sci 50 77-81 XiaZ-Q, Costa MA, Pelissier HC et al (2001) Secoisolariciresinol dehydrogenase purification, cloning, and functional expression. J Biol Chem 276 12614-12623... 

Bannwart C, Adlercreutz H, Fotsis T, Wahala K, Hase T, Brunow G. 1984. Identification of o-desmethylangolensin, a metabolite of daidzein and of matairesinol, one likely plant precursor of the animal lignan enterolactone in human urine. Finn Chem Lett 4-5 120-125. 

SDH in crude protein preparations from Daphne species (Thymelaeaceae) showed the preferential NADP-dependent formation of (-)-matairesinol, although the (-l-)-enantiomer is accumulated in the plant (Okunishi et at, 2004). 

As indicated above, the methylenedioxy bridge of yatein is formed wifh 4, 5 -dimefhylfhujaplicatin as a substrate. The methylenedioxy bridge of bursehemin is, however, direcfly infroduced at the level of matairesinol prior to the methylation of the 4 -OH group (Sakakibara et al, 2003). 

Okunishi, T., Sakakibara, N., Suzuki, S., Umezawa, T. and Shimada, M. (2004) Stereochemistry of matairesinol formation by Daphne secoisolariciresinol dehydrogenase. /. Wood Sci, 50, 77-81. 

Carefully designed labeling experiments have conclusively established the biosynthetic origin of (-)-matairesinol in Forsythia spp. Cell-free enzyme preparations of F. suspensa stems catalyze the stereoselective coupling of two molecules of [8-14C]coniferyl alcohol to form (+)-pinoresinol in enantiomeric excess [24], This reaction likely involves the coupling of free radicals of coniferyl alcohol and is mediated by two enzymes an oxidase and a dirigent protein that controls the... 

Fig. 8.16. Biosynthesis of (— )-matairesinol and related lignans (based on data from Umezawa et al., 1990 a,b).

Biochanin A is degraded to genistein and further to dihydro-genistein, from which 4-ethylphenol and other simple products arise. The bacterial degradation products of matairesinol in the digestive tract are enterolactone (10-126) and lariciresinol. Secoiso-lariciresinol gives rise to enterodiol (10-127), which can be oxidised to the enterolactone. These compounds are excreted in the urine. 

Rather JA, Pilehvar S, De Wael K (2013) A biosensor fabricated by incorporation of a redox mediator into a carbon nanotube/nafion composite for tyrosinase inunobilization detection of matairesinol, an endocrine disrupter. Analyst 138(1) 204—210... 

From bark, valuable chemicals, such as betulinol, can be obtained [5]. Betulinol is used as a health-promoting agent. Recently Holmbom et al. [27, 28] discovered that hydroxymatairesinol (HMR) is concentrated in the stems and knots of Norway spruce Picea abies). It can be extracted and transformed catalytically to matairesinol (MAT), which is an antioxidant and anticarcinogenic agent [29-31]. 

Milder I E, Arts I C, van de Putte B, Venema D P and Hollman P C (2005), Lignan contents of Dutch plant foods a database including lariciresinol, pinoresinol, secoisolariciresinol and matairesinol , Br J Nutr, 93, 393-402. 

On the other hand, biosynthetic pathways that do not involve the conversion from coniferyl alcohol to matairesinol have been proposed for lignans composed of two syringyl (3,5-dimethoxy-4-hydroxyphenyl) groups (+)-syringaresinol formation in Liriodendron tulipifera [50] and (H-)-lyoniresinol biosynthesis in Lyonia ovalifolia var. elliptica [51]. Enantioselective coupling of two sinapyl alcohol units was proposed for the selective formation of (H-)-syringaresinol [50], On the other hand, a non-enantioselective dimerization of sinapyl alcohol was proposed for (+)-lyoniresinol biosynthesis and the enantioselectivity in the biosynthesis was ascribed... 

However, the enantiomeric control by DPs does not lead to the production of optically pure pinoresinol in plants, because the enantiomeric compositions of pinoresinol from various plant species vary widely and optically pure pinoresinol has not yet been isolated from plants [11,13, 53]. Downstream lignans in the lignan biosynthetic pathway, such as dibenzylbutyrolactone lignans including matairesinol, are optically pure [11, 13, 53]. These facts unequivocally indicate that not only was... 

The lignans are a large group of plant phenolics, biosynthesized from the union of two phenylpropane molecules e.g., both matairesinol (Centaurea species, family Asteraceae) and podophyllotoxin Podophyllum peltatum, family Berberidaceae) are formed from the phenylpropane coniferyl alcohol. Lignans are essentially cinnamoyl alcohol dimers, though further cyclization and other structural modifications result in various structural types, e.g. dibenzylbutyrolactone and epoxy lignan. 

Xia et al (2000) proposed a biosynthetic route starting coniferyl alcohol (3.79) and subsequent formation of (+)-pinoresinol (3.82), as shown in Figure 3-12. The enzyme pinoresinol/lariciresionol reductase converts this compound to (+)-lariciresinol (3.87), and then to (-)-secoisolariciresionol (3.88). The enzyme secoisolariciresinol dehydrogenase converts (3.88) into (-)-matairesinol (3.83). The conversion from (-)-matairesinol (3.83) to podophyllotoxin (3.86) is likely to be similar to the route shown in Figure 3-11. 

The main lignan in flaxseed is SDG (Figure 2). Also present are a number of other lignans, that is, matairesinol (MAT), lariciresinol, hinokinin,... 

The palatability of safflower meal to poultry tends to be low (Ravindran and Blair, 1992) due to the presence of two phenolic glucosides matairesinol-p-glucoside, which imparts a bitter flavour, and 2-hydroxyarctiin-p-glucoside, which also has a bitter flavour and has cathartic properties (Darroch, 1990). Both glucosides are associated with the protein fraction of the meal, and they can be removed by extraction with water or methanol, or by the addition of P-glucosidase. 

---