EXTRACTION AND CHARACTERIZATION OF INSECT REPELLING ESSENTIAL OIL FROM PLANTS.A CASE STUDY CHAMOMILE, GARLIC AND CUSTARD

Abstract

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.