## 3 Results
### Total Polyphenol and Flavonoid Contents in SF and SSF Extracts in Different Solvents  
Polyphenols include phenolic acid, flavonoid, tannin, and lignin, and marine algae contain an abundance of polyphenols and secondary metabolites, including flavonoids [41]. The polyphenols and flavonoids in marine algae are essential for survival as they help clear UV-induced reactive oxygen species and support the structural integrity in the sea. Moreover, these components are also beneficial for human health owing to their high nutritional level and have a role in disease prevention [42; 43]. Analysis of the total polyphenol contents in the SF and SSF ethanol, methanol, and water extracts showed that the polyphenol content range across extraction solvents was 4-8 mg TAN/g for SF and 4-10 mg TAN/g for SSF (Figure 1a). The highest total polyphenol content was detected in methanol extracts for both SF and SSF (9.8 mg TAN/g), compared to that of ethanol and water extracts. Interestingly, the highest total polyphenol content in SSF methanol extract was 1.3-fold higher than that of SF methanol extract. The total polyphenol content in SF and SSF ethanol extracts was 4.5 mg TAN/g and 4.8 mg TAN/g, respectively, without a significant difference between SF and SSF content. The lowest total polyphenol content at 4.3 mg TAN/g was detected in SSF water extract. The highest total polyphenol content observed in SF and SSF methanol extracts observed in the present study is in line with the findings of [PERSON] et al. [44], who reported that the SF methanol extract showed higher total polyphenol content than 70% ethanol and water extracts. In addition, phenolic compounds combined with proteins or cellulose have been found, and heat treatment of food was reported to increase the phenolic content through the release of these combined phenolic compounds [45]. This could explain the higher total polyphenol content in methanol and ethanol extracts of SSF than for SF in the present study. The total flavonoid content range across extraction solvents was 0-14 mg QUE/g for SF and 0-13 mg QUE/g for SSF (Figure 1b). The SF and SSF water extracts had the lowest total flavonoid content (1.0 mg QUE/g and 0.4 mg QUE/g, respectively), whereas the SF methanol (13.4 mg QUE/g) and SSF ethanol (12.8 mg QUE/g) extracts showed the highest total flavonoid content. The total flavonoid content in the SSF ethanol extract was 1.4-fold higher than that of the SF ethanol extract. The total flavonoid content in water extract was 1.0 mg QUE/g for SF and 0.4 mg QUE/g for SSF, at markedly lower levels compared to other extracts. [PERSON] et al. [46] measured the total flavonoid content in different extraction solvents (aqueous, ethanol, methanol, and acetone) for _Sargassum swartzii_ and found the highest content in the methanol extract (26.9 mg QUE/g), followed by acetone, ethanol, and \begin{table}
\begin{tabular}{c c c} \hline \hline  & \multicolumn{2}{c}{**Yield (\%)**} \\ \cline{2-3}
**Solvent** & **SF** & **SSF** \\ \hline Ethanol & 8.5 \(\pm\) 0.3 b  & 7.8 \(\pm\) 0.2 b  \\ Methanol & 6.4 \(\pm\) 0.5 b  & 2.9 \(\pm\) 0.1 c  \\ Water & 25.0 \(\pm\) 2.2 a  & 19.0 \(\pm\) 0.9 a  \\ \hline \hline \end{tabular}
\end{table} 
Table 1: The extraction yields of fresh and steamed _Sargassum fusiforme_ extracts. aqueous extracts, which is in agreement with the higher total flavonoid content detected in methanol and ethanol extracts in the present study. Total flavonoid contents varies depending on the determination method used (aluminum nitrate or aluminum chloride assay), the standard compounds used for calculation (quercetin, rutin, morin, etc. ), and the difference in absorbance among individual flavonoids in each extract [47,48]. In this study, an aluminum nitrate colorimetric assay was used for flavonoid content determination. This assay was reported to be specific for measuring flavonoids and flavones [49]. Consequently, the assay indicated that the flavonoids in the SF and SSF extracts were mainly flavonols and flavones.