Glucosinolates – also known as sulfur glucosides or thioglucosides – are a group of glucosides composed of a sugar moiety linked, via a sulfur atom, to the aglycone moiety, derived from amino acids such as methionine , phenylalanine , tyrosine and tryptophan .
As long as they remain sequestered in the sub-cellular compartments of plant tissues, glucosinolates are chemically stable and biologically inactive. Conversely, tissue damage caused by parasites or any other factor that leads to tissue laceration, determines the contact of glucosides with endogenous enzymes called myrosinases. Thus a process of enzymatic hydrolysis (mediated by myrosinases) of glucosinolates is activated, with rupture of the b-thioglucoside bond and formation of unstable intermediaries which rearrange spontaneously into isothiocyanates, thiocyanates or nitriles.
Isothiocyanates are particularly known in the phytotherapeutic field for their lachrymatory, revulsive , rubefacient and vesicant action ; for this reason, some drugs particularly rich in glucosinolates, such as mustard, are traditionally used in the form of poultices and ointments against catarrhal affections, neuralgia and myalgia .
Isothiocyanates are also responsible for the pungent smell and spicy taste of the drugs that contain them, especially the creuciferous or brassicaceae ( turnip , savoy cabbage , cabbage , horseradish , horseradish, Brussels sprouts , mustard , mustard ). If in nature the glucosinolates discourage the aggression of the plant by insects and herbivores, in humans they seem to exert the same activity against tumor cells, as they inhibit some phases of carcinogenesis and induce the apoptosis of numerous cell lines.
To date, more than 130 glucosinolates are known, the concentration of which varies in the various vegetables and in the vegetable itself in relation to the age of the plant, the fertility of the soil, any diseases and the use of growth regulators.
Preserve the anticancer properties of foods rich in isothiocyanates
Among the most studied isothiocyanates for its antitumor properties, we mention sulforaphane , which – concentrated above all in broccoli sprouts – has proved to be active against neuroblastoma (a malignant embryonic tumor characteristic of children) and breast , colon and prostate cancers . Phenylisothiocyanate , originating from gluconasturzine, an aromatic glucosinolate, has shown similar properties, especially in the prevention of lung cancer in smokers.
From indole glucosinolates, such as those contained in mustard , unstable isothiocyanates are released which are rapidly deposited giving rise, among other things, to indole-3-carbinol , which according to various studies appears to have marked antitumor properties.
Glucosinolates, their hydrolysis products and myrosinases are easily inactivated by heat (it is no coincidence that the smell of cabbage becomes all the more intense the longer it is cooked, an indication of the release of sulphur), which justifies the use of fresh food or lightly steamed food . As anticipated, the myrosinase enzyme is released from the cellular vacuoles following wounds or shredding of the various parts of the plant (importance of correct chewing and avoiding excessive chopping of vegetables). It should also be remembered the presence of myrosinase at the level of the intestinal microflora , which contributes to making the isothiocyanates of food origin further available.
Isothiocyanates and thyroid
The high concentration of isothiocyanates in some vegetables has earned them the qualification of ” goitrous ” foods; in fact, these substances inhibit the incorporation of iodine and the formation of thyroxine, slowing down thyroid function . In any case, if the dietary intake of iodine is sufficient, there is no reason to exclude these foods from the diet, the consumption of which should rather be encouraged. In fact, due to the presence of certain glucosinolates, broccoli and cabbage are fully functional foods , considered useful in the prevention of some forms of cancer, such as bladder or breast cancer ., based on the correlation found in recent studies between Brassicacae consumption and reduced cancer risk.
Spicy pasta rings with clams and Roman cabbage – Alice’s Recipes
If it is true that “cancer hates cabbage”, even for many people the relationship with this vegetable is not exactly idyllic. In order for you to appreciate this precious food, it is important to find the right recipe. Alice, the official personalcooker of MypersonaltrainerTv, guides you step by step in the preparation of a tasty first course rich in antioxidants and omega-3 fats .
