Fig. 2

Different concentrations of Zn²⁺ influence the cellulase and xylanase synthesis of the Trichoderma reesei RUT-C30 strain. pNPCase activity (a), CMCase activity (b), xylanase activity (c), FPase activity (d), total protein concentrations (e), and biomass dry weight (f) of the RUT-C30 strain were determined after culturing for 2, 3, or 4 days in liquid MM containing different concentrations of Zn²⁺ (0–5 mM) and 1% (w/v) Avicel as the sole carbon source. The final values are presented as the means ± standard deviation (SD) of the three independent experimental results. Asterisks indicate significant differences compared with the control (*P < 0.05, according to Student’s t-test). MM, minimal medium