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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。 相似文献
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冷饭团化学成分及其活性研究进展 总被引:3,自引:0,他引:3
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。 相似文献
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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. 相似文献
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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. 相似文献
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Yixin Wu Hong Wang Yufu Wang Charles Stephen Brennan Margaret Anne Brennan Caisheng Qiu Xinbo Guo 《International Journal of Food Science & Technology》2021,56(1):196-204
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. 相似文献
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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. 相似文献
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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%。 相似文献
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