Nutritional and antioxidant properties of two species of edible scarab beetles (Cetonia aurata and Oryctes rhinoceros)

Abstract

Edible scarab beetles are important repositories for nutritive and bioactive compounds, but this information remains largely unexplored. This study explored the nutritional and therapeutic properties of two edible scarab beetles from three different locations (Embu, Murang’a and Nairobi Counties) in Kenya. Morphological and molecular characterization of the wild collected larvae revealed two important edible beetle species (Cetonia aurata L. and Oryctes rhinoceros L.). The larvae of both species are excellent source of crude proteins (44% for O. rhinoceros and 63% for C. aurata). The larvae of O. rhinoceros were rich in minerals, particularly calcium (15.75-22.65 mg/g) and potassium (13.62-22.88 mg/g). The anti-radical activity of C. aurata larvae ranged between 91% and 92% across the various target sites. Lysine was the most important and abundant amino acid in both larvae (>5 mg/g). The larvae of C. aurata and O. rhinoceros are a good source of unsaturated fatty acids like Methyl-8Z, 11Z, 14Z-eicosatrienoate (32 mg/g) and Methyl-9Z-octadecenoate (9.47-120.84 mg/g). The entomochemicals of phenolic nature derived from the beetle larvae portray a unique opportunity to supply and improve high quality nutritious food with enhanced ability to get-rid of free radicals, thus promoting good health and well-being of the consumers. Future development of foods supplemented with scarab beetle larvae derived products must consider the preservation of potential benefits of not only nutrients, but also nutraceuticals. However, in-depth research is still needed to guarantee the bioactivity in processed foods and ensure quality control test before the release of these products to the market.