Gas Chromatographic-Mass Spectrometric Analysis of Chemical Components of Oils from Allium sativum L., and Allium cepa L.

Abstract

Garlic (Allium sativum) and onion (Allium cepa) are herbaceous monocotyledonous plants of the Genus Allium and are used the world over for culinary, medicinal and agricultural activities. This study investigated the constituent chemical compounds in the extracted oils of fresh garlic bulbs, and fresh onion bulbs. The fresh garlic and onion bulbs used in this study, were bought at Yankura market in Kano, Kano State, Nigeria. The oils of garlic, and onion were extracted using cold maceration. Constituent chemical compounds of the oils of garlic, and onion were identified using the gas chromatography-mass spectrometry (GC-MS) and the database of the National Institute of Standards and Technology (NIST). Thirty-three chemical compounds, with varying area percentages, were identified in the oil of garlic with retention time ranging from 5.96 to 36.27 minutes. Also, thirty-three chemical compounds with varying area percentages, were identified in the oil of onion, with retention time ranging from 8.3 to 36.49 minutes. Eight chemical compounds namely 9-Octadecenoic acid, N-Hexadecanoic acid, Dodecanoic acid, Tetradecanoic acid, Bromoacetic acid, 9-Oxabicyclo[6.1.0]nonane, Eicosene (E)-, and Carboxylic acid were identified to be common to both the garlic oil, and the onion oil. However, the onion oil had more compound concentration of these chemical compounds common to them both in most cases, than the garlic oil. This factor may confer more bioactivity on the onion oil than on the garlic oil.