四种食用菌菌丝体富集有机钙能力的研究

目的:从硫磺菌、茯苓、红曲和蜜环菌中筛选富钙率和钙有机化程度高的食用菌,并研究富钙高的硫磺菌液体培养时富钙对主要活性成分齿孔酸含量的影响。方法:采用生物富集方法研究无机钙的添加对四种食用菌生长的影响,采用静置浸出法分析菌丝体钙有机化程度,并用高效液相色谱法（High Performance Liquid Chromatography, HPLC）分析硫磺菌主要活性成分齿孔酸的含量。结果:固态培养时,在适宜的加钙量下,硫磺菌的生长均优于茯苓、蜜环菌、红曲。液态培养在加钙量为100 mg/L时,硫磺菌的富钙率显著高于茯苓、蜜环菌和红曲。硫磺菌液态培养加钙量为100 mg/L时,可以达到93.51%的富钙率、85.85%的钙有机化程度和18.34 mg/g的齿孔酸含量,因此硫磺菌具有成为功能性新型补钙产品开发利用的潜质。     

LC-ICP-MS联机技术与同位素稀释质谱法精确测定小麦粉中硒代蛋氨酸

The precise determination of selenomethionine (SeMet) in wheat flour has been performed by species specific isotope dilution mass spectrometric analysis (IDMS) using an inductively coupled plasma mass spectrometer as detector after liquid chromatography (LC-ICP-MS). A labeled ⁷⁶SeMet species-specific isotope enriched spike solution was used for these determinations. The experiment procedure included spiking, extraction, and a simultaneous separation and detection procedure. The method gave yield to good precision (＜2%). The accuracy of the method has been validated on the certified reference materials. The result obtained was in good agreement with the certified reference value. And this method was used to do the international comparison CCQM-K60.     

高纯浓缩硒同位素样品的纯化与分析

利用硒元素的易挥发性,研制了一个用于微量硒样品的蒸发提纯装置,用所建立提纯流程纯化了购买的76Se、78Se和82Se3个浓缩同位素试剂。对比样品分离前后的电感耦合等离子体质谱(ICP-MS)半定量方法测定结果,该方法能够有效地将钠、钾、铁和钨等为主的干扰元素去除,纯化后样品中硒的纯度可以达到99.99%以上,样品回收率约为90%。经多接收电感耦合等离子体质谱(MC-ICP-MS)分析样品纯化前后的硒同位素丰度,整个纯化过程没有改变硒的同位素组成。