## 3 Results
Statistically significant differences in the same element content among the species are expressed by different letters. Regarding the ash content, _S. polyschides_ exhibits the highest amount (20.89 g 100 g\({}^{-1}\)), while _S. lattissima_ the lowest amount (17.81 g 100 g\({}^{-1}\)). The non-indigenous seaweed species _U. pinnatifida_ showed the lowest amount of nitrogen-free extractives (or approximately the carbohydrate content), presenting 48.44 g 100 g\({}^{-1}\), but demonstrated to be a rich protein source (23.54 g 100 g\({}^{-1}\)). _S. polyschides_ and _L. ochroleuca_ stand out for the lowest energy value, where a 100 g portion provides 1180 and 1183 KJ, respectively. Compared with the other analyzed seaweeds, _S. lattissima_ stands out positively for having the highest amount of carbohydrates or nitrogen-free extractives (60.64 g 100 g\({}^{-1}\)) and for providing the highest energy value (1301 KJ/100 g). In contrast, this seaweed has the lowest fiber content, presenting 6.39 g 100 g\({}^{-1}\). Furthermore, the species _L. ochroleuca_ exhibited the highest concentration of fiber (11.65 g 100 g\({}^{-1}\)) and the lowest content of fat and protein (0.51 and 12.83 g 100 g\({}^{-1}\), respectively). Moreover, the seaweeds _S. lattissima_ and _S. polyschides_ also stand out positively for their high total lipid content (1.52 and 1.50 g 100 g\({}^{-1}\), respectively). Fatty acid analysis allowed the identification of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), and highly unsaturated fatty acids (HUFA) in the studied species, with a particular interest in the omega-3 fatty acids encountered (Table 4). In terms of total fatty acids per gram of dried algae, _Undaria pinnatifida_ was the species presenting the highest value, with the contribution of HUFA being particularly high (29% of total FA). Saturated fatty acids were the most abundant class of FA with C16:0 dominating in all species among all fatty acid classes. Significant differences between the four species studied regarding their FA content were somewhat masked by the standard deviations among replicates (Table 4). Nonetheless, clear differences can be observed regarding the contents of C18:3c, C18:3t, and EPA, whereas _Sachorizha polyschides_ and _Undaria pinnatifida_ clearly present higher content of the mentioned FA compared to _Laminaria ochroleuca_ and _Sacharina lattissima_. \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & _U. pinnatifida_ & _S. polyschides_ & _S. lattissima_ & _L. ochroleuca_ \\ \hline Moisture (g 100 g\({}^{-1}\)) & 93.52 \(\pm\) 0.007 a & 87.09 \(\pm\) 0.028 b & 86.07 \(\pm\) 0.007 c & 85.9 \(\pm\) 0.007 d \\ Ash (g 100 g\({}^{-1}\)) & 1.20 \(\pm\) 0.007 a & 2.70 \(\pm\) 0.007 b & 2.48 \(\pm\) 0.007 c & 2.58 \(\pm\) 0.007 d \\ Fat (g 100 g\({}^{-1}\)) & 0.04 \(\pm\) 0.007 a & 0.19 \(\pm\) 0.007 b & 0.21 \(\pm\) 0.014 b & 0.07 \(\pm\) 0.007 a \\ Fiber (g 100 g\({}^{-1}\)) & 0.57 \(\pm\) 0.007 a & 1.36 \(\pm\) 0.014 b & 0.89 \(\pm\) 0.014 c & 1.64 \(\pm\) 0.028 d \\ Protein (g 100 g\({}^{-1}\)) & 1.53 \(\pm\) 0.014 a & 1.81 \(\pm\) 0.007 b & 1.90 \(\pm\) 0.007 b & 1.81 \(\pm\) 0.035 b \\ Nitrogen-Free Extractives (g 100 g\({}^{-1}\)) & 3.14 \(\pm\)0.007 a & 6.85 \(\pm\) 0.014 b & 8.45 \(\pm\) 0.014 c & 7.99 \(\pm\) 0.014 d \\ Energy (Kcal/100 g) & 19.00 \(\pm\) 0.028 a & 36.00 \(\pm\) 0.134 b & 43.00 \(\pm\) 0.177 c & 40 \(\pm\) 0.120 d \\ Energy (KJ/100 g) & 80.00 \(\pm\) 0.106 a & 152.00 \(\pm\) 0.566 b & 181.00 \(\pm\) 0.757 c & 167 \(\pm\) 0.516 d \\ \hline \hline \end{tabular} a  
\end{table} 
Table 2: Nutritional characterization of the fresh biomass of _U. pinnatifida_, _S. lattissima_, _L. ochroleuca_, and _S. polyschides_. Results are expressed in mean \(\pm\) standard error. Statistically significant differences in the same element content among the species are expressed by different letters. (_n_ = 2; fresh weight basis).