Mosquito-borne diseases such as malaria, filariasis, chikunguniya, yellow fever, dengue
and Japanese encephalitis are the major cause of remarkable morbidity and mortality in livestock
and humans worldwide. Since ancient times, aromatic plants are used for their medicinal value.
Essential oils derived from these plants may be used as effective alternatives/adjuvants in
pharmaceuticals, biomedical, cosmetic, food, veterinary and agriculture applications. These oils
have also gained popularity and interest for prevention and treatment of various disorders.
However, several reports on adverse effects including skin eruption, contact artricaria or toxic
encephalopathy in children are available for synthetic repellent in the literature. Thus, natural insect
repellents like essential oils have been explored recently as an alternative. One such essential oil
studied widely, is citronella oil, extracted mainly from Cymbopogon nardus. This essential oil has
exhibited good efficacy against mosquitoes. It is a mixture of components including citronellal,
citronellol, geraniol as major constituents contributing to various activities (antimicrobial,
anthelmintic, antioxidant, anticonvulsant antitrypanosomal and wound healing), besides mosquito
repellent action. Citronella essential oil is registered in US EPA (Environmental protection agency)
as insect repellent due to its high efficacy, low toxicity and customer satisfaction. However, poor
stability in the presence of air and high temperature limits its practical applications. Since specific
knowledge on properties and chemical composition of oil is fundamental for its effective
application, the present review compiles and discusses biological properties of citronella oil. It also
sheds light on various formulations and applications of this essential oil.
Insect GPCRs and TRP Channels: Putative Targets for Insect Repellents
