Influence of the Extraction Mode on the Yield of Hyperoside, Vitexin and Vitexin-2"-O-Rhamnoside from Crataegus monogyna Jacq. (Hawthorn)

Introduction - The extract of Crataegus monogyna shows sedative, hypotensive, vasodilator and cardio-tonic actions. Although several papers dealing with the extraction of metabolites from Crataegus have been published the plant productivity in terms of bioactive compounds in not early understandable as yet. Objective - To investigate the influence of the extraction mode on the yield of bioactive compounds front Crataegus monogyna Jacq. in order to evaluate plant productivity. Methodology - Samples were prepared by extraction of powdered material obtained from top branches, flowers and leaves. Soxhlet extraction, maceration and ultrasound- and microwave-assisted extraction at different experimental conditions were investigated for the exhaustive extraction of hyperoside, vitexin and vitexin-2 ''-O-rhamnoside. The phytocomponents were identified and qualified by HPLC-UV/PAD, comparing HPLC retention times and UV spectra of individual peaks with those of the standards analysed under the same conditions. Results - An easy-to-use HPLC isocratic method suitable for the quantification of hyperoside, vitexin and vitexin-2 ''-O-rhamnoside in raw plant extracts was developed. The optimised HPLC methodology was applied to evaluate different extraction procedures. in raw plant extracts was developed. The optimised HPLC methodology was applied to evaluate different extraction procedures. The ultrasound and microwave-assisted extraction protocols showed higher extraction efficiency than the other. In particular, the optimised microwave protocol gave rise to the highest extraction efficiency with high reproducibility. Conclusions - A microwave protocol combined with isocratic HPLC analysis is proposed for the rapid screening of plant materials collected in different environmental conditions in order to evaluate the productivity of Crataegus monogyna Jacq. and to find out the best ecological conditions to cultivate hawthorn in Northern Italy. Copyright (C) 2008 John Wiley & Sons, Ltd.