Alkaline electrolyzed water-assisted ultrasonic extraction of lutein from daylily (Hemerocallis spp.): Structural preservation and activity evaluation

During lutein extraction, isomerization from all-trans to cis form reduced stability and antioxidant capacity. Alkaline electrolyzed water (AEW), with its reduced-state and small molecular clusters, effectively extracted bioactive substances and inhibited oxidation. Thus, an AEW-assisted ultrasonic extraction method was used to extract lutein from daylily. Compared to ultrasonic extraction alone, AEW treatment increased the lutein yield by 60 %. Structural analysis confirmed the preservation of all-trans lutein by AEW. Assess AEW extraction's impact on lutein's bioactivity by examining its protection against blue light cell damage. The results showed that that lutein extracted using AEW exhibited enhanced antioxidant capacity, significantly boosting the viability of ARPE-19 cells and the activity of intracellular antioxidant enzymes, thereby mitigating oxidative stress damage to the retina caused by blue light exposure. This study provided an effective method for efficiently extracting bioactive substances and preventing the impact of the extraction process on their structure and function.