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Characterization of Essential Oils and Fatty Acids Composition of Stored Ginger ( Zingiber officinale Roscoe)
OFORMA, CC; UDOURIOH, GA & OJINNAKA, C M
Abstract
The essential oils and fatty acids composition of stored Zingiber officinale Roscoe (Ginger) were
characterized using Gas chromatographic-Mass Spectrometric (GC/MS) method. The ginger rhizomes sample was
procured from spices store at Bwari main market, Abuja, Nigeria. It was pretreated and the proximate analysis was carried
out. The essential oils and fatty acids were extracted using Hydro-distillation unit. It was then analyzed using GC/MS.
From the results obtained, the proximate composition showed 8.50% protein content, 3.80% crude fibre, 5.10% fat, 3.60%
ash content, 10.20% moisture and 68.80% carbohydrate content. 38 essential oil components were found and the essential
oil was dominated by the compound class Sesquiterpenes (64.83%) followed by Esters (13.29%), aldehydes (9.16%),
Sesquiterpenols (6.46%) and monoterpenes (5.71%). Monoterpenols constituted 3.35% while ketones and oxides were
seen in trace amounts. The specific dominant constituents were zingiberene (28.57%), Arcurcumene (14.22%) and
Geranyl Acetate (13.28%). There was a decrease in the number of sesquiterpenes and monoterpenes in the stored ginger
compared to the number earlier reported on freshly harvested and dried samples but the reduction did not affect the overall
average percentage composition. The fatty acid comprised 50% saturated acids and 50% unsaturated acids and was
dominated by Linoleic Acid (23.92%) followed by palmitic acid (22.18%), oleic acid (20.40%) and Lauric Acid (8.34%).
The composition of the Zingiber officinale essential oil and fatty acid has shown that the plant contains true essential oils,
implying that the medicinal and flavouring strength of the plants may be attributed to its essential oil composition.
Keywords
Essential Oil; Fatty acids; Ginger; Zingiber officinale
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