title: The glucosinolate-myrosinase system in nasturtium (Tropaeolum majus L.): variability of biochemical parameters and screening for clones feasible for pharmaceutical utilization.
abstract: Leaves of Tropaeolum majus L. contain high amounts of the glucosinolate glucotropaeolin. They are used in traditional medicine to treat infections of the urinary tract. When Tropaeolum leaves are consumed, glucotropaeolin is hydrolyzed to yield mustard oils, which are absorbed in the intestine and excreted in the urine, exhibiting their antimicrobial activity. For a corresponding phytopharmacon, a sufficiently high glucotropaeolin concentration is required and any degradation of glucosinolates while drying must be minimized, i.e. the post mortal cleavage by myrosinases, which are activated by ascorbic acid. In extensive screenings, the dominant parameters determining the glucotropaeolin content in the dried leaves were quantified. It turned out that the glucotropaeolin concentration in the dried leaves represented the most suitable screening parameter. The screening of several hundred Tropaeolum plants resulted in the selection of eight high-yield varieties, from which in vitro plants had been generated and propagated as a source for large field trials.
authors.affiliation: Institute for Plant Biology, TU Braunschweig, Germany.
authors.forename: Maik
authors.initials: M
authors.lastname: Kleinwächter
authors.forename: Ewald
authors.initials: E
authors.lastname: Schnug
authors.forename: Dirk
authors.initials: D
authors.lastname: Selmar
mesh_terms: D001205:Ascorbic Acid / Q000378:metabolism; D004345:Drug Industry; D005961:Glucosinolates / Q000032:analysis / Q000378:metabolism*; D006026:Glycoside Hydrolases / Q000378:metabolism*; D017879:Isothiocyanates / Q000032:analysis / Q000378:metabolism; D018515:Plant Leaves / Q000737:chemistry / Q000201:enzymology / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism*; D032388:Tropaeolum / Q000737:chemistry / Q000201:enzymology / Q000378:metabolism*
chemical_list: D005961:Glucosinolates; D017879:Isothiocyanates; D010940:Plant Proteins; C060321:glucotropeolin; D006026:Glycoside Hydrolases; C022739:thioglucosidase; D001205:Ascorbic Acid