Study On The Extraction And Antioxidant Activity Of Gardenia Yellow Pigment

In order to obtain the optimal&suitable extraction technological routing and parameter of the gardenia yellow pigment, the different extraction technology, such as organic solvent extraction, supercritical-CO2extraction, microwave-assisted extraction and ultrasonic-microwave-assisted extraction were researched. The antioxidant activity of gardenia yellow pigment and its analogues were studied in the thesis. The main contents as following:1. The yield and color scale of gardenia yellow pigment are12.19%and44.89by thermal refluxing organic solvent extraction. the optimal technological parameter for extraction is based on watering bath for3h at70%ethanol as extractant in70℃, solid to liquid ratio of1:10.2. The microwave-assisted extraction of gardenia yellow pigment extraction was studied. Single factor and orthogonal experiments were investigated, such as the solid-liquid ratio, ethanol concentration, extraction temperature, extraction time. The optimum conditions are that solid to liquid ratio1:9, the concentration of ethanol was65%, extraction temperature of70℃, extraction time of9min, extraction of series2, gardenia yellow pigment is relatively extraction rate of12.96%, the color value of45.36with the optimum technology parameters.3. In addition, the ultrasonic-microwave synergistic extraction was studied, the optimum parameters are that liquid ratio1:12, the ethanol concentration60%, extraction power350W, the extraction time was110s, extraction of series2, gardenia yellow pigment is relatively extraction rate of13.38%, color value of45.97;4. the supercritical-CO2extraction was studied and the yield and color value were2.42%and3.09respectively. The Optimal conditions were using60%ethanol as entrainer. extraction temperature is40℃, extraction pressure is40MPa, extraction time of3h, CO2flow rate of12L/h, separated pressure8MPa, the separation temperature is35℃, separation Ⅱ temperature,20℃and other conditions;5. The antioxidant activity of gardenia yellow pigment is different with its analogues. IC50were calculated followed the fitting curves. The Gardenia yellow pigment is more excellent ability to restrain of free radical of DPPH and H2O2according to IC50of clearance.