Abstract:

For the purpose of obtaining a maximum extraction yield of gingerol in the ultrasonic-assisted extraction from ginger, crucial technological parameters including solvent variety, ethanol concentration, extraction time, ratio of material to liquid, extraction times, material particle size and pretreatment method were studied by single factor and orthogonal array design methods. The optimum preparation process of gingerol from fresh ginger was based on drying at less than 60 ℃, grinding, 60 mesh sieving, and once ultrasonic-assisted extraction with 60% ethanol (V/V) for 15 min with a ratio of material to liquid 1:12.5 (m/V). Under such conditions, the extraction yield of gingerol was up to 3.03%. Gingerol exhibited good scavenging effect to hydroxyl and DPPH free radicals in a good dose-dependent manner. Totally 22 compounds were identified in the extract by GC-MS, in which 4 compounds were gingerols and the relative content was up to 31.98%.

Key words: gingerol, ultrasonic, technique, antioxidant activity, gas chromatography-mass spectrometry (GC-MS)