豆类食品中4种大豆异黄酮的含量分析

Determination of the Content of Four Isoflavones in Different Soybean Foods

检测并评估市场上主要豆类食品中大豆异黄酮的含量,进一步补充和完善大豆异黄酮含量数据库。选购日常豆类食品11类,共计51个样品,对样品进行真空干燥、正己烷脱脂、80%甲醇提取处理后,采用高效液相色谱法对其中的4种大豆异黄酮、染料木素、染料木苷、大豆苷元、大豆苷进行检测和分析。结果显示:豆干类为所选样品中大豆异黄酮含量最多的食品,平均含量>600μg/g,嫩豆腐、油豆腐、黄豆芽、绿豆芽、豆浆粉和腐乳类样品中大豆异黄酮含量范围100～600μg/g,豆浆类<100μg/mL,豆奶粉类<100μg/g,酱油和绿豆糕类样品中异黄酮含量低于检出限;腐乳类样品中苷元比例较高,说明该类食品中雌激素样活性成分比例较高。推断豆干、腐乳类食品的长期过度摄入,可能会引发较为明显的雌激素样生物效应。

The objective of the present study was to determine the content of isoflavones in different soybean foods. 11 categories of food samples（n 51） ,were selected from supermarkets that they were commonly eaten in China. After vacuum drying,degreasing with hexane,80% aqueous methanol extraction,4 isoflavones（genistein,genistin,daidzein,daidzin） were analyzed using high performance liquid chromatography（HPLC） . The results showed that the dried beancurd samples contained the highest amount of isoflavones,and the average value exceeded 600 μg/g dry weight,as for other samples,soybean milk contained less than 100 μg/mL,soy milk powder contained less than 100 μg/g dry weight,and the contents of isoflavones were lower than the detection limit in all of the soybean sauce samples and the bean paste cake samples. The remaining 6 samples contained 100～600 μg/g dry weight. Considering from isoflavone composition,the aglycone form occupied a large proportion in all the preserved tofu samples,and it was also showed that these samples have a high estrogenic activity. The result implied that a significant estrogen-like effects may be caused if intaking dried beancurd and preserved tofu for a long time.