ABSTRACT
OBJECTIVE: To optimize extracting parameters of flavonoids from Humulus lupulus. METHOD: Based on the single factors test on ethanol concentration, material and solvent ratio, extracting temperature and extracting time, orthogonal test was performed and the best combination was confirmed. RESULT: With the optimized technology, the maximal extracting amount of flavonoids from H. lupulus was 78 mg x g(-1). CONCLUSION: The optimal techniques obtained are 45% ethanol extracting at 60 degrees C with material and solvent ratio 1:25 for 90 min.
Subject(s)
Flavonoids/isolation & purification , Humulus/chemistry , Plants, Medicinal/chemistry , Technology, Pharmaceutical/methods , Ethanol , Flowers/chemistry , Temperature , TimeABSTRACT
Waste hops are good sources of flavonoids. Extraction of flavonoids from waste hops (SC-CO(2) extracted hops) using supercritical fluids technology was investigated. Various temperatures, pressures and concentrations of ethanol (modifier) and the ratio (w/w) of solvent to material were tested in this study. The results of single factor and orthogonal experiments showed that at 50 degrees C, 25 MPa, the ratio of solvent to material (50%), ethanol concentration (80%) resulted in maximum extraction yield flavonoids (7.8 mg/g). HPLC-MS analysis of the extracts indicated that flavonoids obtained were xanthohumol, the principal prenylflavonoid in hops.
