Clove essential oil was analyzed by gas chromatography-mass spectrometry (GC-MS) on an Agilent 7890 instrument with split stream injector at 270°C. The HP-5 capillary column was 30 m × 0.32 mm with a 0.25 mm film of a cross-linked methyl (95%) phenyl (5%) polysiloxane stationary phase. The initial oven temperature was held at 60°C for 1 min and increased at 10°C/min to 180°C held for 1 min and then ramped at 20°C/min to 280°C maintained for 15 min. The injection volume was 1µl (diluted 1:100 in acetone), and the split ratio was 1:10. The carrier gas was helium at a flow rate of 1.0 ml/min. GC-MS analysis was performed on a GC-MS 6890N gas chromatograph hooked to a 5973N mass selective detector. The GC conditions and capillary column were the same as earlier. The spectra were scanned from 20 to 550 m/z at two scans per second. Most constituents were identified by GC by comparison of retention indices with those found in the literature or those of authentic compounds. The retention indices were determined in relation to a homologous series of n-alkanes (C8-C24, Sigma-Aldrich, St. Louis, and MO) under the same operating conditions. Further identification was made by comparing their mass spectra with those stored in NIST 05 and Wiley 275 libraries or with mass spectra from the literature. Relative percentages of the individual components of the essential oil were obtained by averaging the GC-flame ionization detector peak area% reports (Zhao et al. 2013).