ABSTRACT
The Cymbopogon genus comprises 56 species, and most of them produce essential oil (EO) by hydrodistillation or steam distillation of aerial parts. Various Cymbopogon species, such as C. nardus (L.) Rendle, C. winterianus Jowitt, C. citratus Stapf, C. flexuosus Stapf and C. martinii (Roxb.)
8.1 Introduction .......................................................................................................................... 195 8.2 Methods for EO Analysis: A Summary ................................................................................ 196
8.2.1 Chemical Methods and Fractional Distillation......................................................... 196 8.2.2 Chromatographic Techniques ................................................................................... 197
8.2.2.1 Thin-Layer Chromatography (TLC) .......................................................... 197 8.2.2.2 Gas Chromatography ................................................................................. 197
8.2.3 Hyphenated Techniques ............................................................................................ 198 8.2.3.1 GC-MS and GC-MS Combined with GC(RI) ........................................... 198 8.2.3.2 GC×GC-MS ............................................................................................... 199 8.2.3.3 GC-MS-MS ................................................................................................ 199 8.2.3.4 GC-FTIR, GC-MS-FTIR ...........................................................................200 8.2.3.5 HPLC-MS, HPLC-1H NMR, and HPLC-GC-MS .....................................200 8.2.3.6 Essential Oil Analysis by 13C NMR ..........................................................200 8.2.3.7 Enantiomeric Differentiation ..................................................................... 201 8.2.3.8 Two-Step Procedure ...................................................................................202
