OPTIMIZATION OF PROANTOCYANIDINE EXTRACTION PROCESS FROM FRAGARIA VESCA L. LEAVES

Wild strawberries Fragaria vesca L. have been traditionally used in herbal medicine in treating rashes, as well as internally for treating gastrointestinal catarrh (mucous), diarrhea, intestinal toning, liver health maintenance, catarrh of respiratory passages, rheumatism, nervousness, bladder health maintenance, gravel, fever, in support of vascular health and as a diuretic. The leaves of Fragaria vesca L. are natural source of biologically active substance, such as condensed tannins (epigallocatechins), ellagitannins (pedunculagin and agrimoniin), flavonoids (kampferol and quercetin glucosides) and proantocyanidins (catechin, procyanidin B1). The aim of the current investigation is connected with selection of the best conditions for proanthocyanidins extraction. The influence of the duration of the ultrasonic extraction and solvent system (acetone-water) in different concentration ratio over the extraction process was studied. The optimal conditions for the extraction of proantocyanidins from strawberries leaves were as follow 56% acetone-water solvent system, time of ultrasonic extraction 50 min in ultrasonic bath with frequency 35 kHz. Under these conditions the maximum amount of proantocyanidins 124.0 mg/100 g dry biomass were obtained.