## 3 Results and Discussion
### Solid-State Production of Lignin-Modifying Enzymes by A. olivimuriae  
A further purpose of this work was to verify the presence of ligninolytic enzymes in _A. olivimuriae_ 6C2 solid-state cultures and determine their activity. This strain, mistakenly identified in a previous study as _A. fumigatus_ 6C2, based on ITS sequences and morphological characters, underwent a battery of agar plate tests that indicated the presence of lignin-modifying enzymes (formation of a brown halo in the [PERSON]'s test with tannic acid, decolorization of Poly-R478, formation of ABTS oxidation halos using the underlay agar technique) [65]. In the same study, the strain produced detectable lactose and peroxidase activities in the same work, albeit at low levels. Following the correct identification of this species and sequencing of its genome, this study assessed the presence of putative genes coding for ligninolytic enzymes. Therefore, it was reasonable to expect these enzymes' presence under a cultural condition, such as solid-state fermentation on lignocellulosic-based substrates, which reproduces those encountered in natural habitats. As shown in Table 6, activity levels were very low and in line with those found in the previously mentioned work [65]. Among the non-amended cultures, the best lacase and peroxidase production levels were found in RTB and SCG; in these growth substrates, the presence of WB led to significantly increased lacase and peroxidase activities. However, on the tested substrates, the production levels of these enzymes were markedly lower than those observed in solid-state cultures of other _Aspergillus_ species, such as _A. fumigatus_ SCBM6 and _A. niger_ SCBM1 and ATCC 1004 conducted on different residues [64; 66]. For instance, solid-state cultures of _A. niger_ ATCC \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Culture** & \begin{tabular}{c} **PMG** \\ **(IU g\({}^{-1}\) Substrate)** \\ \end{tabular} & \begin{tabular}{c} **PE** \\ **(IU g\({}^{-1}\) Substrate)** \\ \end{tabular} & \begin{tabular}{c} **PG** \\ **(IU g\({}^{-1}\) Substrate)** \\ \end{tabular} & \
\begin{tabular}{c} **Pectin Lyase** \\ **(IU g\({}^{-1}\) Substrate)** \\ \end{tabular} &
\begin{tabular}{c} **Pectate Lyase** \\ **(IU g\({}^{-1}\) Substrate)** \\ \end{tabular} \\ \hline RTB & 2.30 \(\pm\) 0.18 c & 1.24 \(\pm\) 0.20 c & 1.27 \(\pm\) 0.21 c & 0.33 \(\pm\) 0.08 bc & 0.11 \(\pm\) 0.03 a \\ RTB + WB & 2.99 \(\pm\) 0.27 d & 2.16 \(\pm\) 0.33 d & 1.93 \(\pm\) 0.09 d & 0.31 \(\pm\) 0.01 b & 0.08 \(\pm\) 0.01 a \\ SCG & 0.66 \(\pm\) 0.05 a & 0.39 \(\pm\) 0.03 ab & 0.54 \(\pm\) 0.06 a & 0.17 \(\pm\) 0.05 a & 0.12 \(\pm\) 0.06 ab \\ SCG + WB & 0.73 \(\pm\) 0.08 a & 0.53 \(\pm\) 0.08 b & 0.56 \(\pm\) 0.11 a & 0.15 \(\pm\) 0.01 a & 0.10 \(\pm\) 0.02 a \\ BS & 0.99 \(\pm\) 0.13 a & 0.10 \(\pm\) 0.01 a & 0.74 \(\pm\) 0.11 ab & 0.19 \(\pm\) 0.04 a & 0.20 \(\pm\) 0.04 ab \\ BS + WB & 1.49 \(\pm\) 0.13 b & 0.06 \(\pm\) 0.02 a & 0.91 \(\pm\) 0.11 b & 0.31 \(\pm\) 0.02 b & 0.25 \(\pm\) 0.04 b \\ DSF & 0.49 \(\pm\) 0.12 a & 0.14 \(\pm\) 0.05 ab & 0.52 \(\pm\) 0.07 a & 0.19 \(\pm\) 0.04 a & 0.22 \(\pm\) 0.02 b \\ DSF + WB & 0.71 \(\pm\) 0.09 a & 0.09 \(\pm\) 0.02 a & 0.73 \(\pm\) 0.11 a & 0.46 \(\pm\) 0.05 c & 0.26 \(\pm\) 0.04 b \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Specific activities, referred to unit mass of the solid substrate, of polymethylgalacturonase (PMG), pectin esterase (PE), polygalacturonase (PG), pectin lyase, and spectase lyase in _A. olivimuriae_ solid-state cultures conducted for 14 days at 301.15 K on residual thistle biomass (RTB), spent coffee rounds (SCG), barley straw (BS) e digestate solid fraction (DSF) in the absence and presence of wheat bran (WB). Data are the means \(\pm\) standard deviation of 4 replicates. Multiple pair-wise comparisons were made with [PERSON]’s test, and identical letters denote that column means were not statistically different (\(p\) 0.05). 1004, grown on palm cactus husk, yielded lactose activity, which was around 173-fold higher than the best production achieved with _A.