Ultrasound extracting and determination of capsaicin and dihydrocapsaicin in capsicum
HAN Xiao-lan1, HU Yun-feng1, ZHAO Xue-zhi2, QIU Yang3, LI Xi-xiang3, HE Hong-ju2* (1.College of Food Engineering and Biotechnology, Tianjin University of Science and Technology, Tianjin 300457; 2.National Engineering Research Center for Vegetables, Beijing 100097; 3.Chinese Academy of Agricultural Sciences, Institute of Vegetables and Flowers, Beijing 100081)
Capsaicin and dihydrocapsaicin in capsicum were extracted by ultrasonic method and methanol as solvent. The best way of extracting capsaicin and dihydrocapsaicin: solid- liquid ratio of 1 ∶14, power 150 W, extraction tine 50 min, mentioned tree times. Then analyzed by high performance liquid chromatog -raphy (HPLC) using Shimadzu C18(250 mm×4.6 mm, 5 μm), mobile phase: methanol-distilled water(4∶1), total flow: 0.8 mL/min, wavelength: 280 nm, oven temperature: 30 ℃, injection volume: 10 μL. Good linear relationship between peak area and concentration of capsaicin(in the range of 0.0094～34.99 mg/g) or dihydrocapsaicin (in the range of 0.0011～24.68 mg/g) exists was obtained. The regression equation of Capsaicin standard curve is Y =8333309X +464.34, the correlation coefficient is 0.9999. The regression equation of Dihydrocapsaicin standard curve is Y=6386890X+2962.65, the correlation coefficient is 0.9999. The recovery rates are in the range of 91.34%～95.94%. This method is accurate, convenient and reproducible.