全二维气相色谱-质谱顶空分析总状土木香精油成分OA北大核心

The essential oil of Inula racemosa Hook.f.from Sichuan Province was extracted by steam distillation.A comprehensive two-dimensional gas chromatography-mass spectrometry(GC × GC-MS)analysis method of essential oil of I.racemosa was established,and the GC × GC-MS analysis of volatile components was carried out by headspace sampling method.Based on single-factor experiments,the optimized process conditions of essential oil extraction were as follows:particle size of 0.850 mm,soaking time of 6 h,extraction time of 10 h,liquid-to-material ratio of 10∶1(mL∶g),with an essential oil yield of 1.02％under these conditions.GC × GC-MS was used to analyze the volatile components of I.racemosa under two different extraction methods.A total of 30 components were identified by steam distillation,while 82 components were identified by headspace sampling,with 8 common components,mainly sesquiterpenes.The volatile components and relative contents obtained from I.racemosa showed some differences.The main essential oil components and GC contents identified by steam distillation were 29.65％of alantolactone,at 28.11％of β-elemene,and 12.88％of β-selinene,respectively.In contrast,the main volatile components and relative contents identified by headspace sampling were at 46.34％of alantolactone and 41.17％of isoalantolactone,respectively.The optimized essential oil extraction process and headspace sampling method could be combined to obtain a more comprehensive volatile substances of I.racemosa.Utilizing GC × GC-MS technology for component analysis could serve as a rapid identification method for evaluating the quality of I.racemosa essential oil.