Plant-derived medicinal entomochemicals: an integrated approach to biodiscovery in Australia

Abstract

Despite an ancient and well-established use of insects in traditional medicine, our understanding of their bioactive compounds (entomochemicals) lags far behind that of medicinal plants (phytochemicals). In this review, we focus particularly on insect–plant interactions, to examine the possible dependence of the medicinal properties of insects on phytochemicals that they bioaccumulate or chemically modify. We suggest that a cross-disciplinary approach including ethnobiology, insect ecology and phytochemistry can provide new opportunities in bioprospecting. Such opportunities lie not only in identifying medicinal entomochemicals that are based on phytochemical accumulation or modification but also on using insects as bioindicators of what plants may contain novel phytochemicals that have not yet been studied. Firstly, evidence is drawn from the international literature on the medicinal use of insects, many of which have pharmacological properties now well established in the Western scientific paradigm. Secondly, we highlight the value of a cross-disciplinary approach to bioprospecting in an Australian context, where records of traditional Aboriginal use of medicinal insects are scant. Particularly, we explore the Aboriginal use of Lepidoptera as a case study, including witchetty grubs, hawkmoths and processionary caterpillars. We conclude that opportunities remain to connect traditional, ecological and chemical knowledge for biodiscovery, in collaboration with Indigenous communities. Ultimately, the success of any such endeavour is dependent on the successful conservation management of insect biodiversity into the future.