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Seventeen different samples of Passiflora incarnata were screened for harman alkaloids by a reversed‐phase high performance liquid chromatographic (HPLC) method. Only one sample yielded a possible harman content of approximately 0.1 ppm which was just above the level of detection limit. The method comprises extraction of the plant material, purification and concentration of the alkaloid fraction by combined solid‐phase extractions on Extrelut and cation‐exchange cartridges, and subsequent HPLC analysis using diode‐array and fluorescence detection. The method was found to be sensitive and selective and revealed good recovery. The efficiency of the method was demonstrated with Peganum harmala seeds.

Roman chamomile [Chamaemelum nobile (L.) All. (syn.: Anthemis nobilis L.) (Asteraceaeil is a perannual herb cultivated in Western Europe and in Northern Africa. In traditional medicine the chamomile flowers are used as an anti-inflammatory and spasmolytic tea for stomach problems. The most characteristic constituents are the essential oil, sesquiterpene lactones, and phenolics including flavonoids. Flavonoids are suitable for qualitative and quantitative analysis by . The main flavonoids of Chamaemelum nobile var. plena are apigenin, apigenin 7-0glucoside (6, 7), and apigenin 7-(6",3"-hydroxy-3"-methylglutaroyl)-fi-o-glucoside (8). Some commercial chamomille preparations (e.g. Kamillosan® Asta Medica, FRG) are standardized as apigenin 7-0-glucoside, because of the spasmolytic activity of apigenin derivatives. It is therefore important to have a precise and reproducible method to determine the content of the above-mentioned compounds.Two methods have been developed: the first one is suitable to determine the total amount of apigenin after acid hydrolysis and the second one to quantify the apigenin and apigenin 7-0-glucoside content after alkaline cleavage of the acyl group of apigenin 7-(6",3' ' -methylglutaroyl)-fl-o-glucoside (9, 10).Sample preparation: 0.50 g pulverized flowers were extracted twice with 40 ml of 80% methanol for two minutes with a Polytron® and filtered through a glass filter G4. The plant material was then washed with 10 ml methanol and the liquid extract completed to 100.0 ml with methanol. 1) 10.0 ml of this solution were submitted to acid hydrolysis with 3.0 ml HCI 25% during 2 hours. 2) Another 10.0 ml were mixed with 10.0 ml 1 N NaOH under nitrogen at ambient temperature and neutralized with HC1 25% after 30 minutes.Both solutions were evaporated under reduced pressure to dryness. The residues were dissolved in 5 ml of 70 % methanol and filtered through a C-18 cartridge (e.g. Bond Elut® Varian) preequilibrated with methanol. The cartridges were then washed with 4 ml methanol and the solutions completed to 10.0 ml with methanol. lOpl of each solution were analyzed by HPLC. Chromatographic System: Hewlett Packard HP G1300 Workstation 1090 LC, 1040 DAD; column: Hypersil ODS II, 5pm, 4 x 100 mm; mobile phase: acetonitrile tetrahydrofuran : water: orthophosphoricacid= 14: 14: 71.5 0.5; flow rate: 1.Oml/min; temperature: 25°C; detection: 335 nm, 254 nm. (Results, see Table 1).The acid hydrolysis has the disadvantage of a bad recovery, whereas the alkaline hydrolysis showed a good one. The later is normally done at elevated temperatures (4). As flavonoids are partially destroyed under these conditions, the method used for qualitative analysis (9, 10) carried out at Table 1 Results of RP-HPLC analysis of C. nobile var. p/ens. Method 1 Apigenin Apigenin Method 2 Apigenin 7-0. glucoside Average(n=6) 1.67% 0.43% 2.39% Rel. standard deviation 6.25% 2.99% 6.11 % Recovery rate (n = 3) 83.0 % 94.3 % 89.4 % Rel. standard deviation 7.0 % 7.4 % 3.1 % ambient temperature under nitrogen was adapted for quant...

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