Glucosinolates hydrolysis products

Effects of Isolated Glucosinolate Hydrolysis Products on Insects. 105... 

Natural Variation in Glucosinolate Hydrolysis Products among A. thaliana... 

A major proportion of the glucosinolate hydrolysis products formed upon myrosinase cleavage in some plants are nitriles. In vitro, nitrile formation associated with myrosinase-catalyzed hydrolysis is enhanced at low pH (pH<3) and in the presence of ferrous ions. In vivo, protein factors in addition to myrosinase may be responsible for nitrile formation. If the glucosinolate side chain has a terminal double bond, the sulfur released from the thioglucosidic bond may be captured by the double bond and an epithionitrile is formed.9 This reaction takes place only in plants that possess a protein factor known as epithiospecifier protein (ESP). ESP activities have been identified in several species of the Brassicaceae and shown to influence the outcome of the myrosinase-catalvzed hydrolysis reaction although they have no hydrolytic activity by themselves.10 12 The mechanism by which ESPs promote epithionitrile formation is not known. 

EFFECTS OF ISOLATED GLUCOSINOLATE HYDROLYSIS PRODUCTS ON INSECTS... 

The glucosinolate hydrolysis products most frequently demonstrated to be toxic to insects are the isothiocyanates (Table 5.1). In fact, isothiocyanates have been... 

Table 5.1 Examples of studies showing toxic effects of isolated glucosinolate-hydrolysis products on insects. NCS, isothiocyanate SCN, thiocyanate CN, cyanide (= nitrile).

BENDING, G.D., LINCOLN, S.D., Inhibition of soil nitrifying bacteria communities and their activities by glucosinolate hydrolysis products., Soil Biol. Biochem., 2000, 32, 1261-1269. 

ATTIEH, J., KLEPPINGER-SPARACE, K. F NUNES, C., SPARACE, S. A., SAINI, H. S., Evidence implicating a novel thiol methyltransferase in the detoxification of glucosinolate hydrolysis products in Brassica oleracea L., Plant Cell Environ., 2000,23,165-174. 

Gene Regulation by Glucosinolate Hydrolysis Products from Broccoli... 

The glucosinolate hydrolysis products consist of many complex compounds, two of which are of particular importance isothiocyanates and oxozolodinethiones, both of which are oil soluble. Since the oil comes into contact with the hydrogenation catalyst prior to the admission of hydrogen and since in any event these culprits are adsorbed preferentially by the catalyst, excess catalyst is required solely for their immobilization. Reactor turn around time may be lengthened as well. Some of the glucosinolate derivatives may also remain in the meal and produce unwanted dietary effects in animals and poultry. No method has been found to date that is both practical and economical for the removal of these compounds from the meal. 

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