Figure 2. Activity of antioxidant enzymes in the midguts of bees challenged by N. ceranae.

Differences in enzymatic activity of A) superoxide dismutase (SOD), B) glutathione reductase (GR), C) glutathione peroxydase (GP) and D) glutathione-S-transferase (GST) were estimated by a Mann-Whitney U test. Means±SE are shown for 4 pools of 3 midguts per replicate (n = 3 replicates, 36 bees total/treatment). * and ** denote significant differences at p<0.05 and p<0.01, respectively.