Microwave and enzyme co-assisted aqueous two-phase extraction of polyphenol and lutein from marigold (Tagetes erecta L.) flower

Abstract

In this study, a novel method of simultaneous extraction and enrichment of total polyphenol (TP) and lutein from marigold flower was developed by microwave and enzyme co-assisted aqueous two-phase extraction (ATPE) (MEAATPE). In this study, ethanol/ammonium sulfate was chosen to construct aqueous two-phase system (ATPS) due to its fine partition and recycling behaviors. The optimal MEAATPE condition was obtained, that is, 28% (w/w), ethanol/20% (w/w) ammonium sulfate, 0.45 U/g enzyme concentration, enzymolysis time of 150 min, enzymolysis temperature of 45 °C, microwave time of 120 s, and microwave power of 270 W, by investigating the effects of ATPS composition and other factors on the yield of target products. Under this optimal condition, the yields of TP and lutein reached 84.61 and 7.32 mg/g with the corresponding recovery rates of 95.35% and 99.85%, respectively. Compared with enzyme-assisted ATPE, microwave-assisted ATPE, ATPE, and Soxhlet extraction (SE), the extraction yield of TP by MEAATPE was the highest, which is 71.14% higher than that of SE. Scanning electron microscopy analysis further showed an optative pretreatment effect of marigold flower powders. Thus, MEAATPE was an efficient, rapid, and environmental-friendly method used for the extraction of natural products.