Flaxseed extraction

NDFE, non-defatted flaxseed extract DFE, defatted flaxseed extract. 

FIG. 5 The antioxidant activity of non-defatted flaxseed extract (NDFE), defatted flaxseed extract (DFE), SDG, and tertiary-butylhydroquinone (TBHQ) in stripped corn oil observed by Hall and Shultz (2001). 

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]. 

A dose-dependent decrease in trophoblast tumor cell proliferation was observed in estrogen receptor-positive Jeg3 cells treated with flaxseed extract or certain flaxseed extract fractions, with two fractions producing a 58 to 86% decrease in the production of progesterone. Some extract fractions showed a stimulating effect on hormone production and cell proliferation (Waldschlager et al. 2005). 

Waldschlager, J., C. Bergemann, W. Ruth, U. Effmert, U. Jeschke, R.U. Richter, U. Kragl, B. Piechulla, and V. Briese. 2005. Flaxseed extracts with phytoestrogenic effects on a hormone recep>-tor-positive tumour cell line. Anticancer Res. 25(3A) 1817-1822. 

Flaxseed extract. See Linseed (Linum usitassimum) extract Flaxseed oil. See Linseed (Linum usitatissimum) oil... 

Linseed fatty acids. See Linseed acid Linseed (Linum usitassimum) extract Synonyms Flaxseed extract Linum usitatissimum Linum usitatissimum extract... 

Wanasundara JPD, Shahidi F. 1994. Alkanol-ammonia-water/hexane extraction of flaxseed. Food Chem 49 39-44. 

Various methods could be used to reduce the cyanogenic glycosides content in the seed. Wanasundara et al. (1993) investigated the use of solvents extraction as a means to reduce cyanogenic glycosides content of flaxseed meal. They found that extraction of flaxseed with alkanol-ammonia-water/ hexane resulted in enhanced removal of cyanogenic compounds from 41 to... 

Tocopherols consist of a, (3, y, and 8 isomers and are effective antioxidants. Oomah et al. (1997a) observed that y-tocopherol (9.04 mg/100 g seed) was the predominant isomer of Canadian flaxseed cultivars. Total tocopherol ( r = 0.42) and y-tocopherol (r = 0.41) values were correlated with seed oil content. Kamm et al. (2001) reported the distribution of tocopherols and tocotrienols in high and low linolenic flaxseed. Results were similar to the findings of Oomah et al. (1997a) in which y-tocopherol content was greater (430-575 mg/kg oil) in high ALA flaxseeds, whereas low linolenic flaxseed exhibited lower (170 mg/kg oil) values. Bozan and Temelli (2002) compared tocopherol levels in oil extracted by supercritical C02 fluid and soxhlet (Table XI). Soxhlet-extracted oil had greater tocopherol levels (76.4 mg/100 g oil). These authors speculated that the temperature-pressure combination may have influenced the tocopherol extraction by supercritical C02 fluid. 

In order to improve oxidative stability, supercritical C02 fluid extraction could be used for flaxseed oil extraction (Bozan and Temelli, 2002). This method demonstrated higher ALA content compared to soxhlet extraction. In contrast, tocopherol content was lower (Table XI). Temperature and pressure profiles did not alter the fatty add profile and exhibited similar results at 50 and 70°C and pressures of 35 and 55Mpa. Stability of oil was not reported, and since limited knowledge is available further research is required with regards to shelf life and comparisons to cold-pressing operation. 

FATTY ACID DISTRIBUTION OF LIPIDS EXTRACTED FROM ROASTED FLAXSEED 46... 

CONJUGATED DIENE CONTENT OF LIPID (%, DB ) EXTRACTED FROM SEMOLINA-FLAXSEED, UNCOOKED AND COOKED SPAGHETTI4 e... 

Cui, W., Mazza, G., Oomah, B.D., and Biliaderis, C.G. 1994b. Optimization of an aqueous extraction process for flaxseed gum by response surface methodology. Lebensm, Wiss. U. Technol. 27, 363-369. 

Eliasson, C., Kamal-Eldin, A., Andersson, R., and Aman, P. 2003. High-performance liquid chromatographic analysis of secoisolariciresinol diglucoside and hydroxycinnamic acid glucosides in flaxseed by alkaline extraction. J. Chromatogr. 1012, 151-159. 

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