## 3 Results
### Principal Component Analysis  
Principal component analysis allows us to summarize, clarify, and simplify groups of information given by variables. In this case, the different extraction experiments were used as independent variables. The extraction yield, protein, total glucans, total phenolic content, antioxidant activity (ABTS and ORAC), and cytotoxicity were the dependent variables. PCA enabled us to make graphical representations of distance among the different extraction experiments (Figures 2 and 3).  
In Figure 3, it is possible to observe that the contribution of the variables and the two components explain a cumulative 66.8% of the total variance in the experimental data (component one is 35.5% and component two is 31.3%). Component one is slightly more correlated with all the variables than component two. The total phenolic compounds, cytotoxicity, antioxidant activity (ABTS and ORAC), and protein are positively correlated with component one and the extraction yield and total glucans are negatively correlated with it. Regarding component two, glucans, cytotoxicity, and the ORAC are positively correlated with it, and the extraction yield, total phenolic compounds, protein, and ABTS negatively correlated with it. An analysis of Figure 1 allows us to observe the differentiated extracts from the three different mushrooms. The different extracts from each mushroom are grouped closer to one another. From Figures 2 and 3, we can observe that extracts from _P. eryngii_ showed the highest content of glucans while presenting the lowest amount of protein, total phenolic content, and antioxidant activity (ABTS). _P. ostreatus_ extracts showed the highest total phenolic content and lowest cytotoxicity. As for _A. cylindracea_ extracts, they presented the highest amount of protein and antioxidant activity (ABTS and ORAC) and a good total phenolic content while also showing high correlation with the cytotoxicity variable. Some of the antioxidant activity might have been related to the presence of peptides, as the protein, ABTS, and ORAC variables are positively correlated within the first component.  
PCA allowed us to evaluate and validate the differences among the different mushroom extractions regarding the protein content, total glucans, total phenolic content, antioxidant activity, and cytotoxicity, which were determined analytically. The simple display of the two graphics allows us to observe the behavior of each variable regarding the different mushroom extracts.  
\begin{table}
\begin{tabular}{c c c} \hline \multicolumn{2}{c}{**Extracts (40 mg/mL)**} & **Metabolic Inhibition (\%)** \\ \hline \multirow{3}{*}{_P. ostreatus_} & M1 & \(-27.67\pm 1.46\) \\  & M2A & \(-47.70\pm 5.55\) \\  & M2B & \(-32.52\pm 11.59\) \\ \hline \multirow{3}{*}{_P. eryngii_} & M1 & \(-3.46\pm 6.38\) \\  & M2A & \(-9.45\pm 3.23\) \\ \cline{1-1}  & M2B & \(27.03\pm 5.19\) \\ \hline \multirow{3}{*}{_A. cylindracea_} & M1 & \(34.00\pm 7.00\) \\  & M2A & \(89.00\pm 1.00\) \\ \cline{1-1}  & M2B & \(74.00\pm 12.00\) \\ \hline \end{tabular} Extract M1—hot extraction (1 g of mushroom dry matter (DM); 20 mL of water; 90 \({}^{\circ}\)C, 700 rpm, 1 h); extract M2A—room-temperature extraction (1 g of mushroom DM; 20 mL of water); extract M2B—hot extraction of residue from M2A (1 g of mushroom DM; 20 mL of water; 90 \({}^{\circ}\)C, 700 rpm, 1 h).  
\end{table}
Table 4: Cytotoxicity of extracts M1, M2A, and M2B from _P. ostreatus_, _P. eryngii_, and _A. cylindracea_.