气相色谱-质谱/选择离子监测模式检测食用菌多糖中单糖组成方法的建立与质谱解析

Establishment of gas chromatography-mass spectrometry/selected ion monitoring mode method for the detection of monosaccharide composition in edible fungus polysaccharides and mass spectrometry analysis

中文关键词:  食用菌  多糖  单糖  气相色谱-质谱连用/选择离子监测模式(GC-MS/SIM)  质谱解析

英文关键词:edible fungi  polysaccharides  monosaccharide  gas chromatography-mass spectrometry/selected ion monitoring mode  mass spectrometry analysis

中文摘要:

      目的 建立一种适用于食用菌多糖中单糖组成准确定性定量分析的高灵敏检测方法。方法 选用了香菇、杏鲍菇、海鲜菇和木耳4种食用菌多糖, 经三氟乙酸水解、乙酸酐衍生化后, 采用气相色谱-质谱/选择离子监测模式(gas chromatography-mass spectrometry, GC-MS/SIM)进行分析。用7种单糖混合标准品考察方法的专属性、精密度、线性范围、检出限和定量限, 在不同的m/z下以线性关系最佳为标准选择出各单糖最适宜的定量离子, 并用食用菌多糖样品考察了SIM模式下方法的稳定性和加标回收率。结果 结果表明, 分别选用m/z 115、m/z 103、m/z 115、m/z 115、m/z 115、m/z 115和m/z 103作为核糖、鼠李糖、阿拉伯糖、木糖、甘露糖、葡萄糖、半乳糖对应衍生物的特征定量离子, 各单糖之间分离度均大于1.2, SIM模式下各单糖在10.00~50.00 μg/mL之间线性关系良好, 相关系数(r2)大于0.998, 各单糖的检出限和定量限分别为5.75~22.23 ng/mL和17.26~66.67 ng/mL。以单糖混合标准品、香菇多糖为样品基质, 得出本方法精密度、稳定性良好, 在不同的加标水平下, 各单糖的平均回收率在94.4%~101.3%之间, 并通过质谱解析讨论了五碳糖、六碳糖和鼠李糖的电子轰击离子源质谱的裂解规律, 佐证了选择以上特征离子的合理性, 表明对不同结构的单糖选择不同的定性定量离子, 可达到良好的分离度、提高分析方法的检出限。结论 本研究所建立方法具有良好的分离度、精密度和稳定性, 其灵敏度高于目前已报道的多数同类检测方法, 适用于各类食用菌多糖中单糖组成的检测。

英文摘要:

      Objective To develop a highly sensitive detection method suitable for accurate qualitative and quantitative analysis of monosaccharide composition in edible fungi polysaccharides. Methods Four kinds of edible fungus polysaccharides samples: Lentinus edodes, Pleurotus eryngii, Hypsizygus marmoreus and Auricularia auricula were selected, after hydrolyzing with trifluoroacetic acid, and deriving with acetic anhydride, the sample was analyzed by gas chromatography-mass spectrometry (GC-MS/SIM). The specificity, precision, linear range, limits of detection (LOD) and limits of quantification (LOQ) of this method were investigated with mixed standards of 7 kinds of monosaccharides. At different m/z, the best linear relationship was used as the standard to select the most suitable quantitative ion for each monosaccharide. The stabilities and recoveries of the method under selected ion monitoring (SIM) mode were investigated using edible fungus polysaccharide samples. Results The results showed that m/z 115, m/z 103, m/z 115, m/z 115, m/z 115, m/z 115 and m/z 103 were selected as the characteristic quantitative ions of the corresponding derivatives of ribose, rhamnose, arabinose, xylose, mannose, glucose and galactose, respectively. The separation of each monosaccharide was greater than 1.2, and the linear relationship between each monosaccharide in SIM mode was good between 10.00–50.00 μg/mL, and the correlation coefficient (r2) was greater than 0.998. The LOD and LOQ were 5.75–22.23 ng/mL and 17.26–66.67 ng/mL, respectively. Using monosaccharide mixed standard and lentinan as sample matrix, it was proved that this method had good precision and stability, and the average recovery of each monosaccharide was between 94.4% and 101.3% under different standard adding levels. And the rationality of selecting the above characteristic ions was discussed by mass spectrometry analysis. Conclusion This method has good separation, precision and stability, and its sensitivity is higher than most similar detection methods reported so far. It is suitable for the detection of monosaccharide composition in various edible fungi polysaccharides.