Activity of superoxide dismutase in Galleria mellonella larvae infected with entomopathogenic nematodes Steinernema affinis and S. feltiae

Background. The influence of infection with two species of entomopathogenic nematodes of Steinernematidae family on the activity of superoxide dismutase (SOD) of the host was studied. Material and methods. Last instar larvae of Galleria mellonella were experimentally infected with Steinernema affinis and S. feltiae at 20 invasive juveniles per insect. At 6, 12, 18, 24 and 36 h after infection activity of SOD was determined in extracts from infected and control insects. Results. The activity of SOD decreased gradually in the controls during the experiment. The activity of enzyme was 2-4-times higher in insects from both infected groups than in the control. During the first 12 h of infection the activity of SOD in insects infected with S. feltiae was higher than in those infected with S. affinis, then the activity of enzyme in the insects of both infected groups stayed at a similar level. A significant decrease of SOD activity in infected was recorded in second day of the infection.