Optimization of extraction procedure and determination by high performance liquid chromatography of flavonols and phenolic acids from Hypericum Perforatum L

Hypericum perforatum is a medicinal plant which has been known in traditional medicine as an antiinflammatory and healing agent. Nowadays the use of Hypericum extracts is concerned mainly with antidepressive applications. In the present work, HPLC – RPC18 column chromatography with photodiode array detection was applied for the determination of the derivatives of cinnamic and benzoic acid (e.g., caffeic, chlorogenic, ferulic, sinapic, gallic acids) (Fig.1.) and flavonols quercetine derivatives (quercetine, rhamnetine, quercitrin, mirycetine, keampferol and rutin) in Hypericum Perforatum. Phenolic compounds were extracted from the sample matrix with ethanol and ethanolwater mixture in different ratios solvent (3:7; 8:2; v/v) at 30°C and 60°C in water-bath shaker and by ultrasonic extraction and then analyzed before and after acid and basic hydrolysis. The total amount of studied flavonols and phenolic acids were compared with the total flavonoids content (TFC) and with total polyphenols content (TPC). UV-Vis spectrometry was used to investigate methods for qualitative and quantitative determination of these compounds.