柱前衍生-反相高效液相色谱法检测富硒米曲霉中有机硒形态

建立高效液相色谱法测定富硒米曲霉中有机硒形态的分析方法。采用6 mol/L HCl溶液,50℃水解富硒米曲霉48 h,提取样品中的有机硒,4-氯-3,5-二硝基三氟甲苯柱前衍生,C18反相色谱柱(4.6 mm×250 mm,5μm)分离,以乙腈-水(1∶1,V/V)和p H 6.8乙酸-乙酸钠缓冲液为流动相进行梯度洗脱,紫外检测波长:240 nm,测得富硒米曲霉中有机硒化合物主要是硒代胱氨酸,检出限(RSN=3)为0.680 mg/L,定量限(RSN=10)为2.244 mg/L,线性范围为5.0~100 mg/L,加标回收率为94.8%~105.8%,硒代胱氨酸的含量为1.25 mg/g。本方法简单、灵敏、重复性好,可适用于富硒米曲霉及相关产品中有机硒形态的检测分析。

Determination of Organic Selenium Compounds in Selenium-Enriched Aspergillus oryzae by Pre-Column Derivatization-RP-HPLC Method

A reversed phase-high performance liquid chromatography (RP-HPLC) method for the determination of organic
selenium compounds in selenium-enriched Aspergillus oryzae was established. The extraction of organic selenium compounds
from samples was performed through hydrolysis with 6 mol/L HCl solution for 48 h at 50 ℃. After pre-column derivatization
with 4-chlorine-3,5-dinitrobenzotrifluoride (CNBF), the derivatives were separated on a C18 reversed-phase column through
gradient elution with acetonitrile-water and pH 6.8 acetic acid-sodium acetate buffer solution. UV detection was carried
out at 240 nm. The organic selenium compound in selenium-enriched A. oryzae was mainly selenocystine (SeCys2).
The limit of detection (LOD) (RSN = 3) was 0.680 mg/L and the limit of quantitation (LOQ) (RSN = 10) was 2.244 mg/L.
The linear range was 5.0–100 mg/L. The recoveries were in the range of 94.8%–105.8% and selenium-enriched A. oryzae
contained 1.25 mg/g selenocystine. This method is simple, sensitive and accurate, and could be used to determine organic
selenium compounds in selenium-enriched A. oryzae and related products.