Extraction and purification of narirutin and hesperidin from green yuzu (Citrus junos) and evaluating their biological activities

This study examines how to obtain high levels of two major flavonoids, hesperidin and narirutin, from GY (green yuzu) powder and investigate their biological properties. We selected solvent extraction and enzyme treatment conditions before purification with an HP-20 Diaion column. We determined the appropriate extracted condition as 5 % GY with a 50 % ethanol solvent, and the enzyme treatment condition as 0.05 % RF enzyme for 24 h. Purification using 50 % ethanol as an eluent resulted in highly-enriched narirutin and hesperidin (50.78 % and 42.43 %, respectively). We also investigated the biological activities of extracts from each step, including the assessment of MMP-1 and tyrosinase inhibition activities, antibacterial properties, cytotoxicity, and anti-inflammatory activities. The extracts exhibited desirable properties such as skin elasticity, whitening effects, and anti-inflammatory effects in LPS-simulated RAW 264.7 cells. Highly purified extracts showed better antibacterial activity against food and dermatological pathogens. The results suggested that narirutin and hesperidin concentration and purity may influence the extracts' biological effects. Overall, this study provides valuable insights into the improved extraction and purification of narirutin and hesperidin from GY powder and their biological activities, highlighting their potential as a functional food and health product ingredients.