## 3 Results and Discussion  
### Removal of CR and MG by Fresh Biomass of T. virens and T. viride  
The removal of CR (Figure 2A) showed no significant differences, from 24 h onwards, for the living mycelium of _T. viride_ (93%) and dead mycelium of _T. viride_ (95%) and _T. virens_ (94%). However, the percentage of CR removal by living _T. virens_ showed a constant increase during the experimentation time from 82.4% to 93%. In that respect, it has been reported that some species pre-adapted to azo dyes show better removal properties than untreated culture media [56]. The living mycelium in the two species of _Trichoderma_ had slightly lower removal capability of CR when compared to that described for _Tranetes versicolor_ (100%) and _Tielephora_ sp. (97%); however, the concentration of CR used in the present study (50 mg L\({}^{-1}\)) is higher than those reported for _T. versicolor_ or _Tielephora_ with 31 mg L\({}^{-1}\) and 35 mg L\({}^{-1}\), respectively [57] (Table 1). In contrast, when the CR concentration was 50 mg L\({}^{-1}\), the removal observed for _T. versicolor_, 82%, for _Aspergillus niger_, 9%, for _A. oryzae_, 52%, for _Penicillium chrysogenum_, 10%, for _Cladosporium rubrum_, 10%, and _Pleurotus ostreatus_, 12% [58; 59], were lower than that obtained in the present study. The removal percentages of CR by the dead mycelium of _T. virens_ (94%) and _T. viride_ (95%) are higher than those described for the mycelium of _T. versicolor_ under three conditions: (a) autoclaved (90%), (b) acidic (49%), and (c) alkaline (42%) [58] (Table 1). For MG dye (Figure 2B), the living and dead mycelium of _T. virens_ showed the highest removal percentages, 95% and 87%, respectively. For its part, the dead mycelium _T. viride_ showed 82% of MG removal, whereas the living mycelium showed the lowest removal (75%). Compared to other fungi, the percentage of MG removal showed by the living mycelium of _T. virens_ (95%) and _T. viride_ (75%) was higher than that reported for mycelium of the white rot fungus _Polyporus elegans_ (45%), _T. versicolor_ (43%), _Lenzites betulin_ (57%), _P. simplicissimum_ (89 and 57%), _P. ochrochloron_ (93%), and _Mucor_ (65%) [60; 61] (Table 1). It has been reported that the biomass of some other filamentous fungi shows a higher capacity for removing CR and MG (Table 1). However, _T. viride_ and _T. virens_ have the advantage of growing rapidly in conventional media and agri-food residues and produce, at low-cost, large quantities of biomass, compared to some strains of _Aspergillus niger_, _Polyporus elegans_, _T. versicolor_, and _Pleurotus ostreatus_[62; 63; 64]. It is worth to note that in this research, HgCl\({}_{2}\) was used to kill mycelium and prevent the synthesis of fungal enzymes, according to the methodology of [PERSON] et al. [55]. However, its use is not recommended because of its environmental implications. Another alternative to kill mycelium in an environmentally friendly way is autoclaving [58]. In addition, autoclaving mycelium has been found to increase the adsorption of fungal biomass [26]. To evaluate the adsorption rate, the data obtained from kinetic experiments were fitted using pseudo-first (Equation (4)) and pseudo-second-order (Equation (5)) reaction rate models. The results indicated that the adsorption rates of CR and MG by _T. virens_ and _T. viride_ could be more appropriately described using the pseudo-second-order rate model (correlation coefficient R\({}^{2}\) = 0.99). Figure 3A (CR) and 3B (MG) show plots of experimental data fitted to the pseudo-second-order rate model. Table 2 gives the parameters determined from the linear regression plots (\(t/q_{\text{r}}\) vs. \(t\)) using the pseudo-second-order model and the experimental values of \(q_{\text{e}}\) (\(q_{\text{e,exp}}\)) for both dyes. Figure 2: (**A**) Removal of Congo red (50 mg L\({}^{-1}\)) and (**B**) malachite green (50 mg L\({}^{-1}\)) by fungal fresh biomass (living or dead), for eight days.