Variations in antioxidant defense during the development of the solitary bee Osmia bicornis

An efficient antioxidant system is of particular importance for insects whose high metabolic rates promote increased formation of reactive oxygen species (ROS). The amount of ROS can be additionally increased by environmental factors. This study investigates the ability of red mason bees (Osmia bicornis L.) to inactivate free radicals during insect development. Both male and female bees were studied, from the larval to the active imago stage. The activity of four antioxidant enzymes, superoxide dismutase, catalase, peroxidase and glutathione S-transferase, was measured; and glutathione content and total antioxidant status were determined. The highest values of the examined parameters were found in feeding stages-in larvae and in active imagines of both genders. Significant differences between genders were noted mainly in catalase activity, which was lower in overwintering imagines and active females than in males. Most differences were observed between females and males after emergence.