Activity of ros metabolism enzymes and light emission level of Neonothopanus nambi myccelium under the action of salicylic acid

The metabolism enzymes activity of reactive ox-ygen species (ROS) - NADPH-oxidase, catalase, superoxide dismutase and peroxidase and the in-tensity of light emission in the mechanically dam-aged mycelium of the luminous fungus Neonothopanus nambi without and with addition of salicylic acid (SA) were studied. It was shown that in the conditions of acute experiment, after the me-chanical damage of mycelium samples and its sub-sequent incubation in a nutrient medium for a short time interval (6-7 hours), there was a significant (2 orders of magnitude or more) increase in the light emission of the fungus. A luminescence in-crease was registered against the background of a significant decrease of the superoxide dismutase (SOD) activity and total peroxidase activity in the mycelium. At the same time, the activity level of NADPH-oxidase in the fungus remained virtually unchanged throughout the experiment, but the ac-tivity level of catalase increased slightly. The addi-tion of SA in the incubation medium considerably inhibited the light emission of N. nambi mycelium. Wherein it was shown that the exogenous SA acti-vated all the studied ROS metabolism enzymes, except for catalase activity, which insignificantly decreased. The data obtained is consistent with our earlier hypothesis that the light emission of fungi is an additional mechanism of antioxidant protection against damaging effects of ROS. Significant in-crease in the light emission of the damaged myce-lium with a decrease in SOD activity was observed and especially, total peroxidase activity may indi-cate the start of this mechanism in the fungus for the protection against ROS, first of all H2O2 and other peroxide compounds.