Glucosinolates release

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. 

Disease control by green manure is an artificial application of allelopathy. Isothiocyanates released from cruciferous plants are an example of this allyl isothiocyanate (166), which is derived from the glucosinolate sinigrin (167), is the most popular example.98 Application of Geranium carolinianum for the control of Ralstonia solanacearum, the cause of bacterial wilt of potato, and potato scab, which is induced by some Streptomyces spp., was reported.99 100 One of the antibacterial constituents was shown to be ethyl gallate (168).101... 

Oro was Canada s first B. napus low-erucic acid rapeseed cultivar, developed by Agriculture and Agri-Food Canada, Saskatoon, and released in 1968 (Stefansson and Downey 1995). Oro was developed by pedigree selection in the progeny from the cross of Nugget x Liho. It had an erucic acid concentration of less than 5% and a high glucosinolate concentration of over 150 pmol/g air-dried, oil-free meal. 

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