## 3 Results and Discussion
### Antioxidant Activities of FFL Extracts  
In general, polyphenols contain numerous OH groups, and their contents are positively correlated with antioxidant capacity since the hydroxyl group attached to the free radical terminates the radical with an attached electron [32]. The total polyphenic content of each FFL extract was quantified and compared using the Folin-Ciocalteu reagent. Table 3 illustrates that there were no significant differences in the polyphenol content among the ethanol extracts. Only the hot water extract showed lower polyphenol contents compared to the other ethanol extracts. This tendency was observed in the results of other plant extracts [29; 33]. [PERSON] and [PERSON] quantified the polyphenol and flavonoid contents in edible mushroom extracts. The results showed higher polyphenol contents in ethanol extracts compared to the hot water extract [33]. In addition, [PERSON] et al. observed that an increased proportion of organic solvents facilitated the extraction of an increased range of components, including essential oils, organic acids, polyphenols, and steroids, compared to hot water extraction methods [29]. Collectively, organic solvents seem to provide a more favorable condition for the extraction of polyphenols in FFL. The radical scavenging activity of the FFL extracts was assessed with DPPH reagent. As shown in Figure 3a, FFL extracts at concentrations of 100 \(\mathrm{\SIUnitSymbolMicro g}\)/mL or lower exhibited no significant differences among all the extracts. The condition of the 50% FFL extract  
Figure 2: Mutagenicity activity of two strains by FFL extracts in the presence and absence of S9 mix; (**a**,**b**) TA98 strain; (**c**,**d**) TA100 strain. The number of spontaneous revertant colonies is shown as means \(\pm\) SD. \begin{table}
\begin{tabular}{c c} \hline \hline
**Ethanol Solvent Percentage (\%)** & **Contents (\(\mathrm{\SIUnitSymbolMicro g}\)/mg)** \\ \hline
0 & 84.4 \(\pm\) 13.5 2  \\
30 & 111.3 \(\pm\) 13.8 3  \\
50 & 123.8 \(\pm\) 16.2  \\
70 & 120.7 \(\pm\) 13.5  \\
100 & 119.9 \(\pm\) 15.3  \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Total phenolic contents of the _Fomes fomentarius_ L. extracts. displayed the highest activity at a concentration of 500 \(\upmu\)g/mL, whereas the condition of the 0% FFL extract revealed the lowest activity among all the FFL extracts. This result aligns with the result of the total phenolic contents. The DPPH radical scavenging activity is known to be attributed to the antioxidant effects of phenolic acids, flavonoids, and other phenolic compounds [34]. The total antioxidant capacity was also measured by the ABTS cation decolorization assay (Figure 3b). At a concentration of 10 \(\upmu\)g/mL, there were no significant differences among the FFL extracts. However, the higher antioxidant activity in the ethanol solvent extracts was observed over 100 \(\upmu\)g/mL concentrations than in the hot water extraction. Lastly, the antioxidant capacity was assessed by measuring the reaction between an oxidant and the FFL extracts using the DTT assay method. PQN is in the PAHs group with oxidative properties and was utilized to determine the consumption of the DTT reagent, which reacts with oxidative materials. Thus, the consumption rate of the DTT reagent was measured upon treatment with PQN and FFL extracts (Figure 3c). The condition of PQN exhibited a high DDT consumption of 652.5 \(\pm\) 32 nmol/min/ng. However, when PQN was combined with FFL extracts, the consumption of the DTT reagent decreased in a concentration-dependent manner starting from 10 \(\upmu\)g/mL. Particularly, the 70% ethanol extract displayed minimal DTT consumption of 167 \(\pm\) 28 nmol/min/ug at 10 \(\upmu\)g/mL, indicating robust reactivity with PQN even at low concentrations. Through the antioxidant tests, we confirmed that ethanol extractions displayed higher polyphenol contents and potent antioxidant abilities compared to the hot water extract. Consistent with our results, [PERSON] et al.