Development of Extraction Method for Welsh Onion Root by Alliinase Activation

The objective of this study is to improve allicin extraction from Welsh onion root (Allium fistulosum L.) by adjusting various extraction conditions such as the composition of extraction solvent, extraction time, and alliinase activation. Welsh onion root was extracted at different temperatures, ethanol (EtOH)/water ratios, and extraction periods to collect alliin- and allicin-enriched extract. The extract was analyzed by High Pressure Lipid Chromatography (HPLC) to quantify alliin and allicin. As a result, content of alliin and allicin extracted at 70°C in 70% ethanol for 2 h was 75.992 mg/g and 1.371 mg/g, respectively. In addition, prior to extraction, powdery Welsh onion root was immersed in water shaken for 30 min to activate alliinase in it. The water-soaking treatment improved allicin extraction and resulted in 0.111 mg/g allicin content in the final extract.