## 3 Results  
### Alamar Blue Assay  
An Alamar Blue assay was conducted to evaluate the cytotoxicity of EEP. The test material was considered non-cytotoxic if the relative cell viability of the sample extract was more than 70% of the control group, in line with ISO 10993-5 [38]. There was an inverse relationship between the relative cell viability and concentration of EEP at both fermentation periods. EEP at a concentration of 6.25% and below for both fermentation periods were non-cytotoxic with a relative cell viability more than 70%, as shown in Table 1. On the other hand, for both fermentation periods, the percentage of relative cell viability was less than 25% for EEP at a concentration above 12.5%, reflecting its toxicity towards the cell. The IC\({}_{50}\) concentration of EEP, which represents the point where 50% inhibition of cell viability occurs, was calculated following the dose-response graph recommended by ISO 10993-5 [38]. At 3 months of fermentation, the IC\({}_{50}\) value for EEP was determined to be 10.38% (Figure 1a), while at 6 months of fermentation, it was found to be 10.39% (Figure 1b). In simpler terms, when the concentration of EEP reached approximately 10.38% and 10.39% for 3 and 6 months of fermentation, respectively, approximately half of the treated cells experienced cell death or cytotoxic effects. The Effects of Different Concentrations and Fermentation Periods on the Cytotoxicity of EEP Extracts  
The effect of different treatment groups and fermentation periods on the cytotoxicity of EEP extract was analysed with two-way mixed ANOVA. The data were normally \begin{table}
\begin{tabular}{c c c} \hline \hline \multirow{2}{*}{**Concentrations**} & \multicolumn{2}{c}{**Relative Cell Viability (\% of Control)**} \\ \cline{2-3}  & **3 Months of Fermentation** & **6 Months of Fermentation** \\  & **(Mean \(\pm\) SE)** & **(Mean \(\pm\) SE)** \\ \hline
100\% EEP & 8.25 \(\pm\)0.25 & 8.28 \(\pm\) 0.28 \\
50\% EEP & 9.65 \(\pm\) 0.39 & 9.03 \(\pm\) 0.27 \\
25\% EEP & 11.28 \(\pm\) 0.39 & 10.14 \(\pm\) 0.36 \\
12.5\% EEP & 24.97 \(\pm\) 0.33 & 25.24 \(\pm\) 0.26 \\
6.25\% EEP & 96.20 \(\pm\) 0.21 \({}^{*}\) & 96.06 \(\pm\) 0.30 \({}^{*}\) \\
3.13\% EEP & 99.35 \(\pm\) 0.23 \({}^{*}\) & 99.02 \(\pm\) 0.32 \({}^{*}\) \\
1.57\% EEP & 100.49 \(\pm\) 0.24 \({}^{*}\) & 100.03 \(\pm\) 0.31 \({}^{*}\) \\
0.78\% EEP & 101.13 \(\pm\) 0.23 \({}^{*}\) & 100.82 \(\pm\) 0.24 \({}^{*}\) \\ \hline \hline \end{tabular} SE: standard error. \({}^{*}\) Cell is regarded as viable when the percentage of relative cell viability is more than 70% [38].  
\end{table} 
Table 1: Relative cell viability of different concentrations of EEP at 3 and 6 months of fermentation. Figure 1: Dose–response graph of the Alamar Blue assay with IC\({}_{50}\) at 3 (**a**) and 6 months (**b**) of fermentation. distributed, as assessed with [PERSON]'s test (\(p>0.05\)) and a normal Q-Q plot. There was homogeneity of variance (\(p>0.05\)) and covariances (\(p=0.435\)), as assessed with [PERSON]'s test of homogeneity of variances and [PERSON]'s test of equality of covariance matrices, respectively. Cell viability of MC3T3-E1 cells was expressed as the percentage of reduction. Higher percentages indicated greater Alamar Blue reduction and higher cell viability, and vice versa. Two-way mixed ANOVA revealed that the interaction effects of different treatment groups and fermentation periods on the percentage of reduction were not statistically significant, as shown in Table 2. There was no significant difference in the percentage of reduction of EEP at 3 and 6 months of fermentation periods (\(p>0.05\)). On the other hand, two-way mixed ANOVA showed that the effect of treatment groups was significant. Further post hoc Turkey tests and pairwise comparisons with the negative control and 2.5% NaOCl were run where the mean, mean difference, standard error and \(p\)-value were reported, as shown in Tables 3 and 4. EEP negatively affected cell viability in a concentration-dependent manner (Table 3).