The effect of olive (Olea europaea L.) phenolics and sugar on Drosophila melanogaster’s development

Abstract

Abstract Olive leaves (Olea europaea L.) contain phenolics that are used for various aims and can also be utilized as free radical scavengers and as a powerful antioxidant source. In this study, our aim was to observe the effects of olive phenolics on the survival rate, development, sex ratio, and adult longevity of Drosophila melanogaster Meigen (Diptera: Drosophilidae) fed with sugar and with a sugar-free diet. The amount of malondialdehyde and the activity of glutathione S-transferase were examined with UV-VIS spectrophotometry in third-stage larvae, pupae and adults. For this purpose, dried olive fruit and leaf extracts were added at different concentrations to the insect’s sugary diets. The results reveal that 12 mg/L phenolic fruit extract and 4 M sucrose had a negative impact on the development and survival of these insects. It was also found that phenolic leaf extract and low sugar concentrations changed the sex ratio, leading to fewer females and more males. The use of phenolic fruit and phenolic leaf extracts with increased sugar-based diets raised the amount of oxidation as well as the detoxification activity in this model organism. These results demonstrate that low amounts of sugar and olive phenolics may be used as an adjunct to adult nutrients to improve the insect’s adult characteristics.