Characterization of the Volatile Components of Essential Oils of Selected Plants in Kenya

Abstract

Essential oils are secondary metabolites that plants produce for protection from pests and predators, attraction of pollinators, and seed dispersal. The oils are made up of a mixture of compounds that give a characteristic flavour and odour. Currently, essential oils are receiving great attention in research for their phytochemical and antimicrobial activities. However, there is scanty information on the chemical composition of many plants. This study provides a detailed analysis of the chemical composition of essential oils of ginger, garlic, tick berry, and Mexican marigold in Kenya. The essential oils were extracted by steam distillation and analysed by gas chromatography–mass spectrometry. The study identified a total of 52 different chemical classes from the essential oils of the four different plants that were analysed. Their percentage composition was also found to vary between the test plants. The essential oils of Mexican marigold constituted the highest composition of the identified chemical classes at 71.2%, followed by ginger at 55.8%, while both tick berry and garlic oils constituted 53.8% of the total classes identified. Terpenes constituted the highest composition in the essential oils of all the four test plants. Other major chemical classes included esters, ketones, organosulfurs, alkanes, cycloalkanes, steroids, aromatic hydrocarbons, and alkanols. Some of these chemical compounds have been shown to have a huge utility potential in biopesticides, pharmaceutical, and food industries, and hence, their industrial extraction and purification from the essential oils of these plants are recommended.

Ethnomedical uses, chemical constituents, and evidence-based pharmacological properties of Chenopodium ambrosioides L.: extensive overview

“…Around 330 compounds (including their isomers) have been placed in other extracts/fractions, mainly in essential oil (59.54%). The majority of them were monoterpenes (43.16%) followed by flavonoid [191]. Monoterpenes and sesquiterpenes are natural products and essential oils' main constituents [192,193].…”

Essential Oils as Biocontrol Agents of Early and Late Blight Diseases of Tomato under Greenhouse Conditions

“…Mexican marigold leaves were collected from the field while garlic cloves and ginger rhizomes were bought from the open air market. Five (5) kg each of the raw plant products were prepared for essential oil extraction following the procedure described by Mugao et al [11,22]. e essential oils were extracted following the vertical steam distillation procedure described by Adams [28] as modified by Mugao et al [11,22].…”

“…Five (5) kg each of the raw plant products were prepared for essential oil extraction following the procedure described by Mugao et al [11,22]. e essential oils were extracted following the vertical steam distillation procedure described by Adams [28] as modified by Mugao et al [11,22]. e essential oils were put in air tight bottles and stored in the refrigerator at 4 °C awaiting the greenhouse experiment.…”

“…ey contain different compounds [22] which have fungicidal, nematicidal, insecticidal, acaricidal, and bactericidal properties [23]. Essential oils are becoming popular because they are safe to use and more acceptable by consumers and they potentially have a multipurpose functional use [24].…”

Component Analysis of White Ginger (Zingiber officinale Roscoe) Extract and Red Ginger (Zingiber officinale Rubra) Extract

“…2 The characteristics of essential oils are; easily evaporated at room temperature, have a bitter taste, pleasant smell according to the aroma of the plant that produces them, and are generally soluble in organic solvents. 3 In a fresh and pure state, essential oils are generally colourless. Essential oils are produced from certain plant parts such as the roots, stems, bark, leaves, flowers, or seeds.…”