Supercritical CO2 Fluid Extraction and Antioxidant Activity of Ginger Oleoresin
Ginger oleoresin was extracted from dried ginger powder using supercritical CO2 fluid with the addition of absoluteethanol as a colsolvent. The effects of extraction pressure, extraction temperature, extraction time, particle size of material andamount of absolute ethanol on extraction yields of ginger oleoresin and gingerols were investigated by single factor and orthogonalarray methods. The optimum conditions for ginger oleoresin extraction were determined as the follows: particle size of driedmaterial, below 120 mesh; extraction pressure, 35 MPa; extraction temperature, 35 ℃, and extraction time 2.5 h. Under theseconditions, the extraction yield of ginger oleoresin and gingerols reached 6.08% and 2.78%, respectively. Ginger oleoresin couldeffectively scavenge DPPH free radicals in a significant dose-dependent manner. GC-MS analysis indicated that there were 76compounds identified in ginger oleoresin, of which 16 ones might belong to the gingerol family and the relative content was33.95%. These results suggest that ginger oleoresin is rich in antioxidant components as gingerols.
ZHENG Jun-cheng ，GAO Zhao-jian1，LIU Hui ，JIANG Yong-hong ，HE Hai-yang1，WANG Ran1，TANG Shi-rong
Ginger oleoresin is mainly extracted by supercritical CO2 extraction and solvent extraction. Supercritical CO2 extraction technology is favored by researchers because of its simple process, high extraction efficiency, and no solvent residues.
At present, the research on supercritical CO2 extraction of ginger oleoresin is mostly limited to process discussion and composition analysis, but the relationship between function and composition is less discussed. This experiment mainly studies the supercritical CO2 extraction process and antioxidant activity of ginger oleoresin, and analyzes its chemical composition by gas chromatography-mass spectrometry (GC-MS) to explore the relationship between oxidation resistance and composition. It is ginger oil Further research on the resin provides a reference.
Materials and Methods
Materials, reagents and instruments
Ginger purchased from Xuzhou Farmers Market
Vanillin (purity> 99%) Sinopharm Chemical Reagent Co., Ltd .;
Reagents such as absolute ethanol are commercially available in analytical grade and are distilled on a rotary evaporator before use.
HP 6890/5973 GC-MS (equipped with electron bombardment ion source (EI) and MSD ChemStation data processing system) Hewlett-Packard Company, USA;
HA121-50-01 Supercritical Extraction Unit Nantong Huaan Supercritical CO2 Extraction System Co., Ltd .;
TU-1810 Ultraviolet Spectrophotometer Beijing General Analysis Co., Ltd.
The factors affecting the extraction of ginger oleoresin by supercritical CO2 were discussed through single-factor experiments and orthogonal experiments, and the optimal extraction process parameters were determined:
Fresh ginger was dried by far-infrared at 50 ℃, pulverized through a 120 mesh sieve, 35 MPa, and extracted at 35 ℃ for 2.5 h. The mass extraction rate was 6.08%, and the ginger curcumin extraction rate was 2.78%. Antioxidant activity experiments show that the extract has a strong ability to scavenge DPPH free radicals, and the scavenging ability has a clear dose-effect relationship with concentration. GC-MS analysis identified 76 substances, of which low-molecular-weight olefins were easily volatile 56.66% and gingerols were 33.95%, which fully demonstrated the advantages of supercritical CO2 extraction of flavor components.