Flaxseed metabolism

LUCAS E A, WILD R D, HAMMOND L J, KHALIL D A, JUMA S, DAGGY B P, STOECKER B J and ARJMANDI B H (2002) Flaxseed improves lipid profile without altering biomarkers of bone metabolism in postmenopausal women. J Clin Endocrinol Metab. 87 (4) 1527-32. 

Brooks, J.D., Ward, W.E., Lewis, J.E., Hilditch, J., Nickell, L., Wong, E., and Thompson, L.U., Supplementation with flaxseed alters estrogen metabolism in postmenopausal women to a greater extent than does supplementation with an equal amount of soy. Am. J. Clin. Nutr., 79, 318,... 

Cunnane, S.C. (1995) Metabolism and function of a-linolenic acid in humans, in Flaxseed in Human Nutrition (eds. S.C. Cunnane and L. Thompson), AOCS Press, Champaign, Illinois, USA, pp. 99-127. 

Teoh, K.H., Ford, J.D., Kim, M.R., Davin, L.B. and Lewis, N.G. (2003) Delineating the metabolic pathway(s) to secoisolariciresinol diglucoside hydroxymethyl glu-tarate oligomers in flaxseed (Linum usitatissimum), in Flaxseed in Human Nutrition (eds L.U. Thompson and S.C. Cunnane), 2nd edn. AOGS Fress, Ghampaign, pp. 41-62. 

TD Shultz, WR Bonorden, WR Seaman. Effect of short-term flaxseed comsumption on lignan and sex hormone metabolism in men. Nutrition Res 11 1089-1100, 1991. 

When, however, 13(S)-HPOD was incubated with an ammonium sulphate precipitate of defatted com germ, the resulting 12-oxo-PDA was not optically pure but a mixture of enantiomers in a ratio of 82.18 [35]. The 12-oxo-PDA obtained by incubation of 13(S)-HPOT with flaxseed extracts was found to be a racemic mixture [36]. These results may be due to low or absent allene oxide cyclase activity in the preparations used [34]. The allene oxide cyclase, a novel enzyme in the metabolism of oxygenated fatty acids was partially characterised and found to be a soluble protein with an apparent molecular weight of about 45 kDa which catalysed specifically the conversion of allene oxide into 12-oxo-PDA [34]. The allene oxide was very unstable and was rapidly hydrolysed in aqueous media into stable 12-oxo-13-hydroxy-9(z),15(z)-octadecadienoic acid (a-ketols) [34]. 

Germination is effective in lowering the content of phytic acid in flaxseed. After 8 days of germination, flax seedlings contained 27% lower phytic acid than that present in ungerminated seeds (Wanasundara, 1995). Degradation of phytic acid for the release of phosphorus for metabolic requirements may account for this observation. 

Toure A, Xueming X. Flaxseed lignans source, biosynthesis, metabolism, antioxidant activity, bio-active components, and health benefits. Compr Rev Food Sci Food Saf. 2010 9 261-269. 

Nesbitt PD, Lam Y, Thompson LU. Human metabolism of mammalian lignan precursors in raw and processed flaxseed. Am J Clin Nutr. 1999 69 549-555. 

Eujisawa M, Watanabe M, Choi S-K, Teramoto M, Ohyama K, Misawa N (2008) Enrichment of carotenoids in flaxseed (Linum usitatissimum) by metabolic engineering with introduction of bacterial phytoene synthase gene crtB. J Biosci Bioeng 105 636-641... 

Toure, A. and Xueming, X. Flaxseed Lignans Source, Biosynthesis, Metabolism, Antioxidant Activity, Bio-Active Components, and Health Benefits. Comprehensive Reviews in Food Science and Food Safety 9, (3), 261-269. 

Ford, T.D., Davin, L.B., and Lewis, N.G., Chemopreventive flaxseed lignans Toward bioengineering the metabolic pathways, Proc. 58th Flax Inst. United States, March 23-25, Fargo, ND, 39 8, 2000. 

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