Extraction And Characterization Of Insect Repelling Essential Oil From Plants.A Case Study Chamomile, Garlic And Custard

Abstract

Plant-based repellents have been used for generations in traditional practices as a personal

protection measures against host seeking insects like mosquitoes. Knowledge on traditional

repellent plants obtained through ethnobotanical studies, is a valuable resource for the

development of natural and environmental safe products. Recently, commercial repellents

containing plant based ingredients have gained increasing popularity among customers. These

are commonly perceived as ‘safe’ in comparison to long-established synthetic repellents,

although this is sometimes misconceptions. To the date insufficient studies have followed

standard with pesticides evaluation scheme guideline for repellent testing. There is need for

further standardized studies in orders to better the evaluation repellent compounds and develop

new product that offer high repellence as well as good customers safety. In this study, essential

oils were extracted from chamomile, garlic and custard apple as insect repellent. The plants

samples were randomly collected from the market places where they are available, packaged

and brought to the laboratory ready for extraction and analysis. The essential oils as insect

repellents was extracted from camomile, garlic and custard apple using hydro distillation, the

essential oils was characterised and quantified using FTIR. Also, the insect repelling properties

of the extracted oils was determined using a double choice method. The percentage yield for

the essential oils from the three species was calculated from the relation between the essential

oil mass obtained and the raw material used. FTIR analysis of the extracted essential oils

showed the presence of various functional groups. The field repellent results indicated

difference in susceptibility of volatile chemicals among the species of the tested insects.