The important substances of secondary metabolism include flavonoids and isoflavonoids. The Trifolium pratense L. (Fabaceae) suspension culture's yield of these metabolites is low, thus an attempt was made to increase the production by elicitation. The endogenous signal substances of the plants' defensive responses include jasmonic acid that also functions as a biotic elicitor in the case of exogenous application. In the experiment the authors monitored the impact of 4 different concentrations of jasmonic acid on the Trifolium pratense L. (variety DO-8 and variety DO-9) suspension culture's yield. The culture was cultivated in Gamborg medium to which 2 mg.l(-1) of 2,4-dichlorophenoxyacetic acid and 2 mg.l(-1) of 6-benzylaminopurine were added. The maximum increase in the production of flavonoids was achieved, when compared with the control samples, with both varieties of the 500 micromol concentration (DO-9, 6-hour application by 140%; DO-8, 24-hour application by 65%). The production of isoflavonoids (genistin, daidzein, genistein, and formononetine) was best stimulated in both varieties by the 50 micromol concentration (in the case of DO-9 variety, the 48-hour application increased the content of genistin by up to 845%).

Charles University Prague Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy Heyrovského 1203 500 05 Hradec Králové Czech Republic

New synthetic pyridine derivate as potential elicitor in production of isoflavonoids and flavonoids in Trifolium pratense L. suspension culture