Fig. 6

Metformin reduces ROS levels. To measure intracellular ROS levels, the fluorescent probe DCFH-DA was utilized. Trichoderma reesei QM6a was grown in liquid MM with or without metformin and H₂O₂. (a) Hyphae were treated with DCFH-DA, and the fluorescence intensity was continuously monitored using automatic inverted fluorescence microscopy. (b) Higher green fluorescence intensity indicates increased levels of intracellular ROS. Differential interference contrast (DIC) microscopy was also employed (**p < 0.01)