Glucosinolates isothiocyanate metabolites

Organic isothiocyanates have been isolated from marine fauna and plants . Alkyl, allyl and benzyl isothiocyanates occur in nature as glucosinolates, in plants such as garden cress, horseradish and mustard. Their principal metabolite is a mercapturic acid (26) present in urine. It is analysed by decomposing at pH 5 according to reaction 41 the isothiocyanate is treated with -butylamine (reaction 39, X = S) and the resulting thiourea is extracted and analysed by HPLC. ... 

Pickett JA, Smiley DWM, Woodcock CM (1999) Secondary metabolites in plant-insect interactions dynamic systems of induced and adaptive responses. Adv Bot Res 30 91-115 Pickett JA, Rasmussen HB, Woodcock CM, Matihes W, Napier JA (2003) Plant stress signalling understanding and exploiting plant-plant interactions. Biochem Soc Trans 31 123 127 Pope TW, Kissen R, Grant M, Pickett JA, Rossiter JA, Powell G (2008) Comparative iimate responses of the aphid parasitoid Diaeretiella rapae to alken glucosinolate derived isothiocyanates, nitriles, and epithionitriles. J Chem Ecol 34 1302-1310... 

Among the most important volatile sulfur compounds are hydrogen sulfide (sulfan), various thiols, sulfides, isothiocyanates and heterocyclic sulfur compounds. Precursors of volatile sulfur compounds are usually non-volatile, sensory indifferent sulfur compounds, especially sulfur-containing amino acids cysteine, cystine, methionine and their derivatives, such as S-alk(en)yl cysteine sulfoxides, glucosinolates, thiamine and other compounds. An important sulfur compound is also sulfur dioxide, which is used as a preservative and an inhibitor of enzymatic browning reactions or the Maillard reaction. It also occurs in a small amount as a metabolite in fermentation processes. Sulfur compounds may be accompanied by their selenium analogues at very low concentrations. 

Glucosinolates are the main secondary metabolites found in cruciferous crops. Their presence is made known to us whenever we eat cruciferous vegetable and salad crops as they degrade immediately upon tissue damage to release a small number of products, of which isothiocyanates ( mustard oils ) are the most well known. The chemical structure and concentration to which humans are exposed can be considered a consequence of three processes First, the synthesis and accumulation of the glucosinolate molecule in the crop plants, which is dependent upon both genetic and environmental factors, second the hydrolysis of the glucosinolates to produce isothiocyanates and other products, which can... 

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