Analysis of antioxidant enzymes and total antioxidant capacity in the midgut of Africanized Apis mellifera selected for tolerance to the neonicotinoid thiamethoxam

Abstract

Agrochemicals are considered one of the factors responsible for the decline of bee population in the world, causing a huge amount of losses. The organism of these insects seeks an alternative for their survival and adaptive factors can be triggered, such as the action of antioxidant substances, which can promote protection via the digestive system. This study aimed to evaluate the enzymatic activity and total antioxidant capacity in the midgut of adult Apis mellifera workers that had been selected since 2015 to be tolerant to the neonicotinoid insecticide thiamethoxam. For this, tolerant and non-tolerant honeybees were contaminated with thiamethoxam for 24 hours. Then the midgut was dissected for the enzymatic analysis. The results obtained showed that tolerant bees presented a significant result regarding the enzymatic activity and total antioxidant capacity for the reduction of damage caused by thiamethoxam when compared to the non-tolerant group.