摘 要：建立一种鸡蛋中光黄素(lumiflavin, LF)与光色素(lumichrome, LC)的高效液相色谱检测方法。鸡蛋全蛋及蛋清样品经甲醇超声、离心、正己烷脱脂脱色处理后，下层清液经0.22 μm有机滤膜过滤上机。以甲醇-水（1:1）为流动相，流速为0.8 mL/min等度洗脱，进样量20 μL，柱温30 ℃，在紫外吸收波长260 nm条件下检测。结果表明，在优化条件下LF与LC出峰时间分别为6.10 min与11.61 min，在0.05~5.00 μg/mL浓度范围内，相关系数分别为1.0000与0.9998，加标平均回收率为82.23%~102.07%，检出限分别为0.035 μg/mL与0.043 μg/mL。所建立的方法样品前处理简单、分离速度快、灵敏度高，满足鸡蛋中LF与LC的测定。
关键词 高效液相色谱法；鸡蛋；光黄素；光色素
Determination of Lumiflavin and Lumichrome in Eggs by
High Performance Liquid Chromatography
Xiong Zhi-yu, Zhao Yan-sheng, Chen Li-hong, Dong Ying※
School of Food and Biological Engineering，Jiangsu University (Zhenjiang 212013)
Abstract An analytical method for the determination of lumiflavin(LF) and lumichrome(LC) in eggs by high performance liquid chromatography (HPLC) was established. LF and LC in egg samples were ultrasound extracted with methanol. The solution was treated with centrifuge and n-hexane, and then spare liquor was passed through a 0.22 μm organic filter for HPLC analysis. The HPLC isocratic elution method was used with methanol-water (1:1) as the mobile phase with a flow rate 0.8 mL/min. The injection volume was 20 μL, the column temperature was 30 ℃ and the detection wavelength was 260 nm. The retention times of LF and LC were 6.10 min and 11.61 min, and the correlation coefficients were 1.0000 and 0.9998 in the range from 0.05~5.00 μg/mL. The average recovery rates ranged from 82.23% to 102.07%, and the detection limits were 0.035 μg/mL and 0.043 μg/mL, respectively. This method was simple, fast, sensitive and suitable for the determination of LF and LC in eggs.
Keywords high performance liquid chromatography; egg; lumiflavin; lumichrome
核黄素又名维生素B2，呈橘黄色结晶针状[1]，是人和动物维持机体正常结构与功能的必需营养物质，易因日光和紫外线的照射破坏。其降解物主要成分为与其结构类似的光黄素(lumiflavin, LF)与光色素(lumichrome, LC)物质[2-4]。光黄素又名三甲基异咯嗪，分子式为C13H12N4O2，光色素又名二甲基异咯嗪，分子式为C12H10N4O2。其结构式如图1所示。迄今关于LF与LC化合物的研究报道并不多见。KINDACK D G等人[5] 曾在猪肾和猪饲料中分离出一种未知物，并鉴定其为LC，认为饲料中LC的来源为核黄素降解产生；TUBEROSO C I等人[6]在蜂蜜中检出LC物质，把其作为鉴别蜂蜜种类的标记物；此外，也有一些关于根际微生物产生LC作为信号因子刺激植物生长，在生物循环中发挥重要作用的报道[7-8]。
鸡蛋由蛋黄、蛋白及蛋壳三部分组成，含有蛋白质、脂类、维生素、矿物质等多种营养素，其中核黄素含量为0.3mg/100g左右[9]，是人类已知的营养最为丰富的食物之一。早期有学者报道日本科学家在鸡蛋中分离出能抑制致癌病毒（EB病毒）的增殖和防止正常细胞发生癌变的成分LF与LC[10]，然而对LF与LC的分离、鉴定方法则未提供相关的信息，后续至今也未见对LF与LC抑制致癌病毒等生物活性研究的进一步报道。曾有学者用液相色谱对豆浆[11]、蜂蜜[8]等样品中LF与LC进行了测定，尚未见对禽蛋类样品中LF与LC的检测报道。
作者：熊治渝，赵延胜，陈力宏，董英