The secoiridoid glucoside secologanin is the terpenoid building block in the biosynthesis of terpenoid indole
alkaloids. A method for its determination in plant tissues and in cell suspension cultures has been developed.
This assay is based on the condensation of secologanin with tryptamine, yielding strictosidine, in a reaction
catalysed by the enzyme strictosidine synthase (STR; E.C. 4.3.3.2). Subsequently, the formation of
strictosidine is quantified by high performance liquid chromatography (HPLC). STR was isolated from
transgenic Nicotiana tabacum cells expressing a cDNA-derived gene coding for STR from Catharanthus
roseus. The high specificity of STR for secologanin, in combination with a sensitive and selective HPLC
system, allows a simple extraction of secologanin from plant tissue. The detection limit of this method is
15 ng secologanin. Using this assay, secologanin contents were determined in tissues of various plant species;
Lonicera xylosteum hairy roots were found to contain 1% of secologanin on a dry weight basis. # 1998 John
Wiley & Sons, Ltd.info:eu-repo/semantics/publishedVersio