## 3 Results and Discussion
### Anaerobic Digestion (AD) of OFMSW and Bio-Delignificated GW
Reduction in digestion time along with increased biogas production are yet more advantageous outcomes of bio-delignification of GW co-digested with OFMSW. Attaining the shortest digestion time is a key variable to using the smallest reactor volume and minimizing the cost of operation. Reduction in digestion time means increased substrate biodegradability and, therefore, it is an indicator of enhanced efficiency during anaerobic digestion. BMP values are also reported. The measured average methane content values in cumulative biogas were 55% from OFMSW and 54% from GW, in accordance with the values reported in the literature [76]. \begin{table}
\begin{tabular}{c c c} \hline \hline \multirow{2}{*}{**Substrate**} & **Productivity** & **BMP** \\  & **(Nm\({}^{3}\)/ton FM * day)** & **(Nm\({}^{3}\) CH\({}_{4}\)/ton VS)** \\ \hline OFMSW & 145 & 141 \\ Untreated GW & 102 & 95 \\ OFMSW + untreated GW & 125 & 146 \\ OFMSW + GW treated with BA & 283 & 289 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Parameters of the AD and anaerobic co-digestion processes considered in this study (OFMSW = organic fraction of municipal solid waste; GW = green waste; BA = _Bjerkandera adusta_; FM = fresh matter; BMP = biochemical methane potential; VS = volatile solids). Figure 2: Daily production of biogas from the co-digestion of OFMSW and GW, treated with BA and untreated, compared with AD of the sole OFMSW and untreated GW. Since biogas production was collected discontinuously, the conjunction lines have the sole function of helping with the comprehension of daily trends and do not correspond to continuous measurements. OFMSW = organic fraction of municipal solid waste; GW = green waste; BA = _Bjerkandera adusta_; AD = anaerobic digestion. It is worthwhile noting the difficulty of comparing these values with others found in the literature for BMP and those related to other GW pretreatments and co-digestion with OFMSW because of the great heterogeneity of the materials utilized. By comparing our results with those reported in the literature regarding different fungal pretreatments of agricultural residues and their effects on biogas yield improvements, we can see that _B. adusta_ could ensure a promising combination between biogas yield increase and time of treatment. Table 5 is a comparative evaluation describing the combination of biological treatment and biogas production with references to the published literature. Despite _B. adusta_ pretreatments of GW being eco-friendly, cost-effective, and seemingly not affected by sugar losses [41; 47; 65; 71], in comparison with other chemical treatments, it is a time consuming process, which must have a detrimental effect on the overall process costs. This application deserves a specific technoeconomic analysis that accounts for capital costs, energy consumption, requirements of chemicals, and waste management; fungal pretreatment imposes extra costs, which often forms a chief hindrance for industrial scaling up of lignocellulosic biomass. It is worth noting that with respect to the other fungal pretreatments (Table 5), _B. adusta_ could ensure the best performance in terms of both time of treatment and biogas yield improvement. The activities and generation of ligninolytic enzymes secreted by white-rot fungi are influenced by several characteristics such as the availability of substrate, moisture content, incubation time, temperature, O\({}_{2}\) concentration, pH, and nutrients supplementation. The optimization of the process is crucial for efficient pretreatment for high fungi activity and production of ligninolytic enzymes, and subsequently higher lignin digestion, for reducing process costs and for managing a scaling up at the industrial level.