Authors
Title
Abstract
Hawthorn is among the plants with a high content of biologically active compounds; their concentration in a ready-to-use extract depends, among other things, on the extraction parameters used. The objective of the research study was to optimise the extraction conditions (temperature, time duration and concentration of solvents) in order to provide the highest possible antioxidant potential of preparations produced from lyophilised anatomic parts of hawthorn (Crataegus × macrocarpa L.), i.e. from its flowers, leaves and fruits. The extraction was carried out at a temperature of 20 ± 2 ºC with the use of three solvents, each one of two concentrations, during 2- and 24-hour periods. The efficiency of ultrasoundassisted extraction was also compared. The antioxidant potential was determined using ABTS˙+, DPPH˙, FRAP and CUPRAC methods and a reducing power test. Additionally, the content of polyphenols and flavonoids was determined. For the purpose of getting extracts from hawthorn flowers, the most effective method was the 24-hour extraction with 70 % acetone and 1 % formic acid added. Those extracts were characterised by the highest value of ABTS˙+, CUPRAC and FRAP antioxidant potential. Then, as regards the extracts from hawthorn fruit and leaves, the highest antioxidant potential was found after the 24-hour extraction supported by double sonication. The highest values of the potential under determination were obtained in extracts from hawthorn fruit extracted with 50 % acetone when using the ABTS˙+ and CUPRAC methods. As for theextracts from hawthorn leaves, the highest values of the antioxidant potential were determined using the DPPH˙ and CUPRAC methods, and the reducing power test. As regards the antioxidant potential, the most effective solvent to extract hawthorn lyophilisates was 70 % acetone-water solution assisted by an ultrasound or 1 % formic acid.
Keywords
hawthorn, extraction, antioxidant potential, flavonoids, total polyphenols