Pavel Musil

Seasonal Variation of Bioactive Alkaloid Contents in Macleaya microcarpa (Maxim.) Fedde

Macleaya microcarpa (Maxim.) Fedde belongs to the genus Macleaya, family Papaveraceae. Together with the better known and more frequently studied species M. cordata (Willd.) R. Br. it is a main source of quaternary benzo[c]phenanthridine alkaloids. Using HPLC we determined the content of eight isoquinoline alkaloids in the aerial and underground parts of 1-, 2-, 12- and 13-year old plants and followed their changes during the vegetative period. The dominant alkaloid of all samples collected in the end of this period was allocryptopine (3.8–13.6 mg/g for aerial parts, 24.2–48.9 mg/g for underground parts). Chelerythrine, sanguinarine and protopine were also present in both parts of the plant. Additionally, measurable concentrations of chelilutine (CL), chelirubine (CR), macarpine (MA) and sanguirubine (SR) were detected in underground parts. The most important finding was that contents of CR, CL, SR and MA in the 12- and 13-year old plant roots were significantly higher (approximately 3-fold for CR, 6-fold for CL, 5-fold for SR, and at least 14-fold for MA) than in 1- or 2-year old plants. The proportion of individual alkaloids in aerial and underground parts thus changed significantly during the vegetative period.

DETERMINATION OF GENTIOPICROSIDE IN EXTRACTS OF CENTAURIUM ERYTHREAE AND GENTIANA LUTEA BY MICELLAR ELECTROKINETIC CAPILLARY CHROMATOGRAPHY

Micellar electrokinetic capillary chromatography has been developed as a promising method for the determination of gentiopicroside in plant samples. The separation conditions have been optimised with respect to the different parameters including SDS concentration, pH, and ion strength of the background electrolyte, and temperature of capillary. A buffer consisting of 100 mM SDS in 20 mM sodium dihydrogen phosphate, 20 mM disodium tetraborate pH 8.6 was found to be the most suitable electrolyte for this separation. The applied voltage of 28 kV (positive polarity) and the temperature of capillary 20°C gave the best analysis of gentiopicroside. The linear detection range for concentration versus peak area for the assay is from 5 to 500 μg. mL−1 (correlation coefficient 0.9998) with a detection limit of 0.3 μg . mL−1. The inter-day reproducibility of the peak area was below 2.5% and the inter-day reproducibility of the migration time was below 0.16 %.