高效液相色谱法测定食品中叶绿素a和叶绿素b的含量

Determination of chlorophyll a and chlorophyll b content in food by high performance liquid chromatography

中文关键词:  食品  叶绿素a  叶绿素b  高效液相色谱法

英文关键词:foods  chlorophyll a  chlorophyll b  high performance liquid chromatography (HPLC)

中文摘要:

      目的 建立高效液相色谱法测定食品中叶绿素含量的分析方法。方法 以提取溶剂、提取方式、提取时间为考察因素,设计正交试验,对绿宝石甜瓜、黑米和菠菜中叶绿素的提取条件进行选择,确定提取叶绿素最优条件为甲醇溶液,超声提取2 min。色谱条件：C₁₈色谱柱(150 mm×4.6 mm, 5 μm),柱温30℃,流动相为甲醇,等度洗脱,流速1.0 mL/min,叶绿素a吸收波长是665 nm,叶绿素b吸收波长是468 nm。结果 叶绿素a和叶绿素b在0.50～20.00 μg/mL范围内与峰面积有良好的线性关系。绿宝石甜瓜、黑米、菠菜和绿茶中叶绿素a和叶绿素b精密度的相对标准偏差均小于5%,加标回收率均在90.0%~100.0%之间,表明方法精密度好,添加回收率高。结论 实验建立的方法重复性好、准确度高,可以准确定量食品中叶绿素的含量。

英文摘要:

      Objective An analytical method was developed for determining chlorophyll in foods by high performance liquid chromatography (HPLC). Methods The extraction solvent, extraction method and extraction time were the investigation factors, and the extraction rate of chlorophyll was the evaluation index. The orthogonal test was designed to optimize the extraction conditions of chlorophyll in emerald melon, black rice and spinach. The optimal conditions were determined as methanol solution and ultrasonic extraction for 2 min.Taking the type of extraction solvent, extraction method and extraction time as the investigation factors and the extraction rate of chlorophyll as the evaluation index, the orthogonal test was designed to optimize the extraction conditions of chlorophyll in emerald melon, black rice and spinach. The optimal conditions were determined as methanol solution and ultrasonic extraction for 2 min.The separation of chlorophyll were achieved on C₁₈ column(150 mm×4.6 mm,5 μm)using methanol as the mobile phase isocratic elution at a flow rate of 1.0 mL/min. Chlorophyll a absorption wavelength 665 nm, chlorophyll b absorption wavelength 468 nm and column temperature were set at 30℃, respectively. Results The linear range of chlorophyll a and chlorophyll b was 0.50～20.00 μg/mL. The relative standard deviation(RSD) of chlorophyll a and chlorophyll b were all less than 5% in emerald melon, black rice, spinach, green tea. The average recovery rate of chlorophyll a and chlorophyll b were between 90.0% ~ 100.0%, indicating that the method had good precision and high spiked recoveries. Conclusion The established method has good repeatability and high accuracy, and can accurately quantify the content of chlorophyll in foods.