不同干燥方式下测定华美牛肝菌中麦角甾醇的含量

Determination of Ergosterol in Neoboletus Magnificus by Different Drying Methods

试验在不同干燥方式下华美牛肝菌中麦角甾醇的含量变化.麦角甾醇大量存在于牛肝菌中,是一种重要的植物甾醇,受到紫外线照射时可转化为维生素D_2,但其含量易受干燥方式的影响.本实验将十八烷基三甲氧基硅烷(ODTMS)修饰过的磁性纳米粒子用作磁分散固相萃取(MDSPE)的吸附剂,并利用HPLC对不同干燥处理方式下华美牛肝菌提取液中的麦角甾醇含量进行测定.对影响萃取效果的条件,包括皂化条件、吸附与解吸附时间、吸附剂用量及解吸附条件进行了考察.在最优萃取条件下,本方法的日间精密度和日内精密度RSD分别为2.1%和3.2%,麦角甾醇在0.027～1.08 mg/mL范围内呈良好线性关系,加样回收率为98.02%.结果显示不同干燥方式对华美牛肝菌中麦角甾醇含量影响差别较大,其中冷冻干燥对麦角甾醇保存程度最好,含量为7.92 mg/g,微波干燥对其破坏程度最大,含量为1.05 mg/g.

In this experiment,the contents of ergosterol in different drying methods were investigated.Ergosterol,an important plant sterol,can be converted into vitamin D2 when exposed to ultraviolet light,and abounds in Neoboletus magnificus,but its content is susceptible to drying method.In this experiment,iron magnetic nanoparticles assembled with octadecyltrimethoxysilane(ODTMS)are used as an adsorbent for magnetic dispersive solid phase extraction(MDSPE).The content of ergosterol in N.magnificus treated with different drying methods was determined by HPLC.The principal influence factors during MDSPE,including saponification conditions,extraction and desorption time,amount of magnetic adsorbent and desorption conditions were investigated.Under the optimum conditions,the inter-day precision and intra-day precision for ergosterol were 2.1%and 3.2%,respectively.The results showed a good linear relationship in the range of 0.027-1.08 mg/mL,and the recovery was 98.02%.Distinctively,the content of ergosterol under different drying methods differs from each other,and freeze-dried could better preserve the ergosterol with the content of 7.92 mg/g,while the microwave damaged most of the ergosterol with the content of 1.05 mg/g.