Glukosinolater

Glukosinolater are a diverse group of sulfur-containing secondary metabolites found primarily in the plant family Brassicaceae, which includes cabbage, broccoli, kale, mustard, and horseradish. They are glycosides composed of a glucose moiety linked to a sulfur- or nitrogen-containing aglycone with a side chain that is derived from amino acids such as methionine, valine, tryptophan, or phenylalanine. The side chain determines the specific glucosinolate name, such as glucoraphanin, sinigrin, and glucoerucin.

In intact plants, glukosinolater are relatively stable and stored in specialized cells. When plant tissue is damaged, the enzyme myrosinase catalyzes hydrolysis of the glucosinolate to produce a variety of breakdown products, most notably isothiocyanates (for example sulforaphane from glucoraphanin), but also nitriles and thiocyanates depending on conditions and proteins present. The composition of breakdown products is influenced by pH, temperature, metal ions, and the presence of specifier proteins.

Biological and health aspects: Some isothiocyanates are studied for potential anti-cancer properties, cellular defense, and anti-microbial effects. Others can act as goitrogens, potentially affecting thyroid function in iodine-deficient individuals; overall dietary impact depends on amount, preparation, and iodine status.

Dietary and culinary notes: Glukosinolater levels vary by species, cultivar, growing conditions, and storage. Cooking methods, such as heating, can reduce levels or alter breakdown products. Crunchy raw cruciferous vegetables tend to preserve myrosinase activity, while processing and extensive heating diminish it.