气相色谱质谱法分析大叶和小叶迷迭香香气成分

Analysis of aroma compounds in large leaf and small leaf Rosmarinus officinalis by gas chromatography-mass spectrometry

目的分析大叶和小叶迷迭香的香气成分差异。方法应用混合水平均匀试验优化顶空固相微萃取(headspace solid-phase microextraction,HS-SPME)条件,采用二次多项式逐步回归分析,确定最优固相微萃取条件。气相色谱质谱法(gas chromatography-mass spectrometry,GC-MS)分析大叶迷迭香和小叶迷迭香香气成分,采用偏最小二乘判别式法(partial least squares-discriminate analysis,PLS-DA)分析不同迷迭香的香气成分。结果HS-SPME最佳条件为饱和度10.0%的氯化钠溶液、平衡时间为13.0 min、萃取时间为42.0 min、装液量为3.2 mL、萃取温度为80.0℃。通过GC-MS分析共检测到123种挥发性物质,其中11种酯类、22种烯类、8种烷类、3种酸类、20种醛酮类、39种醇类、2种醚类、5种酚类、9种芳香烃、4种其他物质。大叶迷迭香中检测出91种物质,小叶迷迭香中检测出86种物质。基于迷迭香香气成分的相对含量建立PLS-DA模型,可区分大叶和小叶迷迭香。结论本研究成功建立了鉴别大叶和小叶迷迭香的方法,分析了大叶和小叶迷迭香的香气成分差异,为迷迭香品质评价提供一定的理论依据。

Objective To analyze the difference of aroma components between large leaf and small leaf Rosmarinus officinalis,and establish a method for discriminating them.Methods The headspace solid-phase microextraction(HS-SPME)conditions were optimized by mixed level uniform experiment.The optimal conditions of HS-SPME were determined by quadratic polynomial stepwise regression analysis.The aroma compounds of large leaf and small leaf Rosmarinus officinalis were analyzed by gas chromatography-mass spectrometry(GC-MS).The aroma components of different Rosmarinus officinalis were analyzed by partial least squares-discriminate analysis(PLS-DA).Results The optimum conditions of HS-SPME were sodium chloride solution with 10.0%saturation,equilibration time of 13.0 min,extraction time of 42.0 min,liquid loading of 3.2 mL and extraction temperature of 80.0℃.One hundred and twenty-three kinds of volatile compounds were detected by GC-MS,including 11 kinds of esters,22 kinds of alkenes,8 kinds of alkanes,3 kinds of acids,20 kinds of aldehydes and ketones,39 kinds of alcohols,2 kinds of ethers,5 kinds of phenols,9 kinds of aromatic hydrocarbons and 4 kinds of other substances.Ninety-one kinds of substances were detected in large leaf Rosmarinus officinalis and 86 kinds of substances were detected in small leaf Rosmarinus officinalis.PLS-DA model was established based on the relative content of Rosmarinus officinalis aroma components,which could distinguish large leaf and small leaf Rosmarinus officinalis.Conclusion The identification method of large leaf and small leaf Rosmarinus officinalis is successfully established,and the difference of aroma components between large leaf and small leaf Rosmarinus officinalis is analyzed,which provids a certain theoretical basis for the quality evaluation of Rosmarinus officinalis.