" Cyanogenic glycosides: physiology and regulation of synthesis "
Flaxseed’s role as the "nutraceutical food of the 21st century" is enhanced by its potential effect on breast and colon cancer prevention, according to Dr. Lilian Thompson, Professor, Department of Nutritional Sciences, Faculty of Medicine, University of Toronto. Dr. Thompson was part of the symposium "Flaxseed in Human Nutrition" at the 16th International Congress of Nutrition in Montreal in July 1997. Dr. Thompson presented data on flaxseed and its effect on breast and colon cancer prevention. Flaxseed is the richest plant source of lignan precursors — important because the lignans that mammals produce from this food precursor have been shown to be protective against breast and colon cancer. In animal studies, Dr. Thompson found that flaxseed affects all three stages of cancer development — initiation, tumour development and tumor growth and spread. "Human studies are needed to confirm, but flaxseed has tremendous potential to positively affect our health," Dr. Thompson said.
Flaxseed contains Secoisolariciresinol diglucoside (SDG), a potent antioxidant and a known precursor of the mammalian lignans, enterolactone and enterodiol. These compounds have other pharmacological properties including phytoestrogen properties similar to isoflavones. Studies performed in the Department of Physiology, College of Medicine, University of Saskatchewan, have shown that SDG prevents the development of hypercholesterolemic atherosclerosis, reduces total cholesterol and LDL-cholesterol, and has a tendency to raise HDL-cholesterol in animal models. In addition, SDG has shown the ability to lower blood pressure, and has demonstrated that it is effective in preventing diabetes mellitus (Type I and Type II) and endotoxic shock.
New (soft) technologies (as pioneered by Gaia Research) can produce products that extend the nutraceutical properties ascribed to flaxseed while minimizing drawbacks associated with the consumption of whole flaxseed, which are usually consumed associated with baked goods, which damages the EFA’s and other healthful components. Correctly processed raw flaxseed can have reduced levels of the strong laxative/purgative effects normally associated with the high cyanogenic glycoside mucilage component of flaxseed, which otherwise releases toxic hydrogen cyanide via auto-hydrolysis in the presence of water in the gut. Although this is associated with a non-targeted additional laetrile-type of anti-cancer effect, it strongly limits the amount of the most healthful SDG, which could otherwise be consumed. A typical concentration of SDG in oil-free flaxseed is around 1.5%. Careful processing can concentrate the SDG, whilst reducing the glycosides, allowing for a much-reduced gastric challenging serving size suitable for an optimal daily dosage.
Cyanogenic glycosides and cyanohydrins in plant tissues.
Biosynthesis of cyanogenic glycosides.
Although ingestion of the cyanogenic glycoside was associated with a significant teratogenic response, the effects occurred only at doses that elicited signs of maternal intoxication (Frakes et al., 1985).
“A novel cytotoxic flavonoid glycoside from .” 2001 Aug.
During cassava starch production, large amounts of cyanoglycosides are released and hydrolysed by plant-borne enzymes, leading to cyanide concentrations in wastewater as high as 200 mg/litre (Siller & Winter, 1998).