Specific plant product
Information relating to Brassica
Relevance to Human Health
Refs
IsothiocyanatesUnderlying genetic variation has led these vegetables to produce higher amounts of particular compounds than do other plants in our diet.Particularly strong evidence obtained for the reduction in the risk of cancer of the gastro-intestinal tract and lung9, 10
>20 independent dietary epidemiological studies have provided evidence that Brassica consumption reduces risk of cancer.
As well as genetic differences between any particular brassica variety grown, the amounts of beneficial compounds entering our bloodstream from vegetables are affected.
Considerable effort at understanding and manipulation levels and metabolic pathways leading to delivery of brassica-specific anti-carcinogenic compounds in diet.
11, 12, 13, 14, 15, 1
The genes in brassicas uniquely enable the production of a particular class of biochemicals (glucosinolates) which break down to compounds (isothiocyanates such as sulphoraphane) known to provide some protection against a range of human cancers
Isothyocyanates are modulators of Phase 1 and 2 enzyme activity
Isothiocyanates neutralise cancer-causing chemicals that damage cells, and by interfering with tumour growth.
Protective effect of Brassica consumption and decrease in risk of cancer is related to Human GST genotype
Significant effects in cabbage and broccoli
Antiproliferative activities
17
FolatesBrassica contains folates ranging from Glu
4 to Glu
8 Nutritional demands for folates are particularly high during
pregnancy. Folate supplemenation prior to conception can significantly reduce the incidence of neural tube defects. Folate deficiencies has also been implicated in the etiology of
megalobastic anemia,
Spina bifida,
neuropsychiatric disorders and various forms of
cancer18,
19,
20
Consultation by the UK Health Departments and the Food Standards Agency on the Report of the Committee on Medical aspects of food and nutrition policy on Folic Acid and the prevention of disease
21
Trace elements SeleniumSupplementation studies on humans have demonstrated the efficacy of selenium (Se) for prevention of colon cancer. The metabolism of Se depends upon its chemical form, and that which occurs in broccoli appears to be particularly effective at protecting laboratory animals from cancer22
PhenolicsQuercetin occurs in relatively high concentration in some brassicas (100-450 mg kg-1) compared to other fruits and vegetables. However, many brassicas contain many other of phenolics, comprising both flavonol glycosides and hydroxycinnamic acid estersFlavonols are important antioxidants.17
Brassica OilsOilseed rape/Canola. Fatty acid compositionLipid profiles may have significant effects on obesity. There also is emerging evidence to show that lipid profiles improve on a controlled-carbohydrate diet23
Nervonic acid
Since nervonic acid is an important constituent of brain and membrane phospholipids, it is vital that the body has an adequate provision of this fatty acid. If, for any reason, the body cannot make this lipid, then a dietary source is indicated. Two such situations are under active investigation; multiple sclerosis (MS), where there are indications that there is inadequate provision of nervonic acid; and premature birth, where the infant no longer benefits from maternal nutrition.
24, 25, 26
Synthesis of Brassiodol utilises rapeseed oil as vehicle of iodination
A new iodised oil, called Brassiodol, is proposed to prevent or eradicate 127I-deficiency disorders inlcuding goitre.
27
Vitamin C Apes and humans require but cannot synthesise ascorbic acid (Vit C)due to lack of an enzyme gulonolactone oxidase. Ascorbic acid has to be supplemented mainly through fruits, vegetables and tablets34, 35, 36, 37
Vitamin EHRI has research focused on post-harvest levels of Vitamin C in broccoli (affecting bioavailability).Ascorbic acid esters have also been shown to have promising anticancer activity compared to ascorbic acid.
Considerable scope for increasing levels of Tocopherol (Vit E) in brassicas