Abstract

In the present study, volatiles from different organs (leaves, roots, and spikelets) of Cymbopogon schoenanthus L. Spreng were investigated. The samples were collected from Oued Sbaa, El-Menia (Algeria) and analyzed for the first time by headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). In addition to this green technique, cryogenic grinding using liquid nitrogen was performed on all samples to minimize the volatile loss. Results of HS-SPME (adsorption and affinity-based) were compared with those of essential oils extracted by hydrodistillation (heating-based) as a conventional extraction method and revealed remarkable variability. Findings showed also similarities in leaves and spikelets volatile mainly composed of monoterpene and sesquiterpene hydrocarbons; however, the volatile profile of the roots presented a specific composition dominated by sesquiterpene hydrocarbons and oxygenated sesquiterpenes. The effects of HS-SPME extraction parameters such as the temperature of headspace (45°C and 55°C), type of fiber coating (PDMS and PDMS/CAR), and the salting-out effect (sodium chloride at 20 %) were also studied. The results display that salt adding has considerably reduced the extraction efficiency of the analytes. Temperature presented two opposing effects on the composition. PDMS/CAR fiber revealed a great performance over PDMS. The multivariate statistical analysis including the hierarchical cluster analysis (HCA) and the principal component analysis (PCA) were used and showed many differences amongst the selected plant parts and the studied parameters. The results showed the possibility of HS-SPME-GC-MS application as a complementary tool for the characterization of the chemical composition of C. schoenanthus L. Spreng.

摘要

在本研究中，香茅不同器官（叶、根和小穗）的挥发物L. Spren 进行了调查。样品从埃尔梅尼亚（阿尔及利亚）的 Oued Sbaa 收集，并通过顶空固相微萃取 (HS-SPME) 与气相色谱-质谱联用 (GC-MS) 联用进行了首次分析。除了这种绿色技术外，还使用液氮对所有样品进行了低温研磨，以最大限度地减少挥发损失。将 HS-SPME（基于吸附和亲和）的结果与通过作为传统提取方法的水蒸馏（基于加热）提取的精油的结果进行比较，发现了显着的变异性。研究结果还表明，主要由单萜和倍半萜烃组成的叶片和小穗也有相似之处；然而，根的挥发性特征呈现出以倍半萜烃和氧化倍半萜为主的特定成分。HS-SPME 提取参数的影响，例如顶空温度（45°C 和 55°C）、纤维涂层类型（PDMS 和 PDMS/CAR）和盐析效应（20% 氯化钠）为也学过。结果表明，加盐显着降低了分析物的提取效率。温度对组合物呈现两种相反的影响。PDMS/CAR 纤维显示出优于 PDMS 的出色性能。使用了包括层次聚类分析（HCA）和主成分分析（PCA）在内的多变量统计分析，显示了所选植物部分和研究参数之间的许多差异。C. schoenanthus L. Spreng。