反相高效液相色谱法测定苹果中槲皮素的含量

采用反相高效液相色谱法测定了苹果肉和苹果皮中槲皮素的含量。将样品于-80 ℃冷冻24 h后,在2,6-二叔丁基对 甲酚的保护下加入6 mol/L盐酸制成匀浆,于90 ℃恒温水浴中回流水解2 h。水解液在反相ODS柱上分离,以甲醇-水(体积 比为55∶45,乙酸调pH值为3.3)为流动相,在波长370 nm处进行测定。结果表明:苹果肉中槲皮素的平均含量为3.11～10.78 μg/g;苹果皮中槲皮素的平均含量为253.57～744.59 μg/g;苹果肉中槲皮素的平均加标回收率为100.4%。该法操作简 便易行、结果准确可靠。

Determination of Quercetin in Apples by Reversed-Phase High Performance Liquid Chromatography

A method for the determination of quercetin in pulp and peel of apples by reversed-phase high performance liquid chromatography with internal standard was developed. Samples were frozen at -80 degrees C for 24 h, then added 6 mol/L hydrochloride under the protection of antioxidant 2,6-di-tert-butyl-p-cresol. The slurry was hydrolyzed thermostatically at 90 degrees C for 2 h and centrifugated for 10 min. The separation was performed on an ODS column (150 mm x 6.0 mm i.d., 5 microm). Methanol-water (55:45, v/v) (pH adjusted to 3.3 with acetic acid) was used as the mobile phase with a flow rate of 1.0 mL/min. The injection volume was 20 microL. The detection wavelength was 370 nm. The results showed that the quercetin content in pulp and in peel were 3.11-10.78 microg/g and 253.57-744.59 microg/g, respectively. The mean recovery of quercetin in apple pulp was 100.4%. The method is simple, accurate, and reliable.