UPLC-MS/MS法测定食品中的4种木酚素

建立超高效液相色谱-串联质谱法同时测定食品中4种木酚素(包括亚麻木酚素、芝麻素、芝麻林素和芝麻酚)的分析方法。试样采用含1 mol/L氢氧化钠(NaOH)的70%乙醇水溶液提取,盐酸调节pH至4~4.5,用70%乙醇水定容。以甲醇和0.1%甲酸水为流动相梯度洗脱,经C18色谱柱分离;采用电喷雾电离源,正离子模式(ESI+),选择反应监测模式扫描(SRM),外标法定量。结果表明:4种木酚素在0.040~10μg/mL浓度范围内线性关系良好,相关系数R在0.9995~0.9999之间;相对标准偏差(RSD)为1.0%~3.1%;在50~2.00×103 mg/kg的加标浓度范围内,回收率为95.0%~101%。亚麻木酚素、芝麻酚、芝麻素、芝麻林素的检出限分别为0.1,0.1,0.03和0.1 mg/kg。该方法分离效果好,灵敏度和准确度高,简单快速,适用范围广。     

冷饭团化学成分及其活性研究进展

对国内外冷饭团化学成分及其生物活性研究现状作了综述。冷饭团主要含有木脂素类成分,这类化学成分具有保护肝脏、抗氧化、抗HIV病毒、拮抗血小板活化因子等活性,并对后续的研究方向进行了展望。     

Separation of 4’-demethyldeoxypodophyllotoxin from Sinopodophyllum emodi by medium-pressure LC and high-speed counter-current chromatography guided by HPLC-MS

A minor lignan, 4ˊ-demethyldeoxypodophyllotoxin, was isolated from Sinopodophyllum emodi. First, a crude extract of S. emodi was analyzed by high performance liquid chromatography-mass spectrometry (HPLC-MS) to confirm the presence of the target compound. Then, the target lignan was successfully enriched in the crude extract precipitate by medium-pressure LC (MPLC) with high recovery (85%). Finally, an efficient separation was achieved by high-speed counter-current chromatography (HSCCC) using a two-phase solvent system of n-hexane-ethyl acetate–methanol–water (1:1:1:1, v/v/v/v). These results clearly demonstrate that the combination of HPLC-MS, MPLC, and HSCCC could be a powerful technique for the rapid screening, enrichment, and separation of minor compounds from complex natural products.     

芝麻萌发工艺条件及抗氧化成分含量变化研究

以芝麻为原料,V_E、芝麻木酚素为评价指标,采用单因素实验、正交实验及相关性分析方法,对芝麻最佳萌发工艺条件及萌发过程中芝麻主要抗氧化成分含量变化进行研究。结果表明,芝麻最佳萌发工艺条件为芝麻∶水=50∶50 g/g、萌发温度35℃、萌发时间8 h。工艺优化后芝麻木酚素含量达到748.83 mg/100 g,较优化前提高了5.39%;芝麻木酚素和V_E含量呈正相关,工艺优化后V_E含量达到546.3 mg/kg,较优化前提高了4.50%。     

碳酸钾催化合成芳基萘内酯类木脂素

以二氯乙烷作溶剂,炔酸烯丙酯在K2CO3催化下,可以顺利发生分子内串联环化反应得标题化合物,产率65％ ～88％.产物经1HNMR、13CNMR和GC-MS确证.     

Comparison of lignans and phenolic acids in different varieties of germinated flaxseed (Linum usitatissimum L.)

The study aimed to evaluate the biosynthesis and accumulation of lignans, phenolic acids and also the antioxidant activities in 15 varieties of flax sprouts. The differential contents of lignans (13.30–8987 μg g⁻¹) and phenolic acids (72.55–597.1 μg g⁻¹) among 15 varieties of flax sprouts were observed. The total antioxidant activities ranged from 147.2 to 332.8 μmol TE g⁻¹ in the flax sprouts. The expression levels of five genes in the lignin synthetic pathway were analysed using RT-qPCR, and the results showed dramatical differences among different flax sprouts. Relatively dispersed analysis was showed by principal component analysis (PCA), and 15 flax sprouts were grouped by hierarchical cluster analysis (HCA) based on their phenolic acids, lignan compounds, length, gene expression and antioxidants after germination, primarily in relation to variety specificity. Present results would be instructive guidance for bio-fortification breeding and functional foods innovation in flaxseeds.     

索氏法提取五味子中木脂素

采用索氏提取法提取水浸预处理后的五味子中的木脂素,考察了虹吸次数、液固比、颗粒粒径及乙醇浓度对萃取率的影响,采用响应面法进行优化. 结果表明,五味子醇甲的最佳提取条件为：乙醇浓度98.05%(j),液固比67.20 mL/g,颗粒平均粒度0.33 mm,该条件下理论萃取率为80.90%,实际萃取率为77.17%;五味子甲素的最佳提取条件为：乙醇浓度96.38%(j),液固比72.52 mL/g,颗粒平均粒度0.21 mm,该条件下五味子甲素理论萃取率为77.11%,实际萃取率为74.31%;五味子乙素的提取最佳条件为：乙醇浓度96.38%(j),液固比72.52 mL/g,颗粒平均粒度0.21 mm,该条件下理论萃取率为77.13%,实际萃取率为74.23%. 各因素对木脂素提取率影响的显著性顺序为乙醇浓度>液固比>颗粒粒径.     

亚麻籽木酚素粗提物纯化工艺优化和评价

从榨油后的亚麻籽饼中提取木酚素,并对纯化工艺进行了研究.在乙醇提取和碱水解同步进行后,选用AB -8大孔树脂进行纯化,并对其纯化步骤进行了优化和评价.实验结果表明:得到的粗提物木酚素干物质得率为(7.78 ±0.31 )mg/g,使用AB -8大孔树脂,选择60％乙醇作为洗脱溶剂对粗提物进行纯化,得到纯度为41.9％、得率为6.50 mg/g(干物质得率)的木酚素纯化物,说明亚麻籽在榨油后有进一步提取木酚素的利用价值.     

亚麻籽和亚麻籽油理化特性及组成分析

以5个品种亚麻籽为原料,分析和研究不同品种亚麻籽油的基本理化指标、脂肪酸分布、甘三酯组成,测定了亚麻籽及油中木脂素含量以及亚麻籽油中维生素E含量。结果表明:亚麻籽中粗脂肪质量分数为45%左右,油中不饱和脂肪酸含量较高,主要为亚麻酸(C18∶3/Ln),相对质量分数为49.20%~55.43%,其次是油酸(C18∶1/O),相对质量分数18.69%~28.21%,亚油酸(C18∶2/L)相对质量分数为10.85%~16.73%,总不饱和脂肪酸质量分数达到88%以上;亚麻籽油中主要的甘三酯为OLn Ln(17.27%~20.50%)和Ln Ln Ln(11.91%~17.02%);高效液相色谱法测定亚麻籽油中维生素E含量均达到6.59 mg/100 g以上;采用紫外可见分光光度计法分析测定亚麻籽和亚麻籽油中木脂素(SDG)的质量分数,分别为1.53%~3.69%和0.03%~0.22%。     

亚麻籽有效成分的提取及其综合利用研究进展

亚麻是一年或多年生草本植物,在我国北方干旱半干旱地区大面积种植。亚麻籽是亚麻的种子,目前国内外对亚麻籽的开发主要侧重于对亚麻籽油的提取,而亚麻籽其他功能活性物质未得到有效开发利用。综述了亚麻籽油、亚麻籽胶、亚麻籽蛋白、亚麻籽木脂素4种天然有效成分的含量、组成、生理功能、提取技术以及在相关领域的应用等研究进展,旨在为亚麻籽有效成分的提取和综合开发利用提供技术参考。