engleski

Effect of extraction conditions on extraction yield, total polyphenolic content and antioxidant capacity of yarrow (Achilea millefolium L.)

In search for novel, functional foods, the food industry is turning towards utilization of herbal extracts in food products. The use of medicinal plants, a widespread source of bioactive compounds with well documented functional properties is becoming more appealing for the food industry. Yarrow (Achilea millefolium L.) is widespread in a moderate climate regions of Europe, North America and Asia. It is rich in flavonoids, tannins, sterols, asparagine and salicylic acid. In order to obtain the highest possible amount of bioactives, efficient extraction procedures are required. To keep the extraction “green”, only water and ethanol can be used as solvents. The aim of this paper is to optimize and define the effect of extraction conditions on extraction yield, total polyphenolic content and antioxidant capacity of yarrow. Particle size, duration of the extraction process, mixing speed and temperature were taken into account as factors influencing the water extraction of bioactive compounds from yarrow. Taguchi orthogonal array was used as an experiment design method. Based on the obtained results, the following extraction conditions resulted in the highest extraction yield (0.82 % of dry mater): particle size less than 100 µm, 30 minutes extraction at 80 °C and 500 min-1 speed of the magnetic stirrer. These conditions also represent the optimal conditions for extraction of the antioxidant compounds (0.42 mmol/g of dry matter analyzed by the ABTS assay and 0.51 mmol/g of dry matter analyzed by the DPPH method) and total polyphenols (44.87 mg GAE/g dry matter). Based on the results of this study, temperature, duration, particle size and mixing speed have a simultaneous influence on the extraction yield, total polyphenolic content and antioxidant capacity of yarrow extracts.

extraction ; optimization ; particle size ; temperature ; yarrow

Ovaj rad doprinos je projektu "Primjena mikroreaktora u praćenju antioksidacijske aktivnosti samoniklog bilja (MICRO-AA)" projektni broj HR.3.2.01-0069, koji je financiran iz Europskog socijalnog fonda (ESF) putem operativnog programa Razvoj ljudskih potencijala.