Table 1.

Concentration of FAAs (μg amino acid per g dried A. nodosum extract) obtained using different solvent types (deionised water, 0.1 M HCl and 1% citric acid) and extraction times (1 and 2 h)

FAAs	Extraction conditions
	Deionised water		0.1 M HCl		Citric acid (1%)
	1 h	2 h	1 h	2 h	1 h	2 h
Asp	96.74 ± 2.96	nd	498.51 ± 26.61	1105.66 ± 7.11	481.08 ± 22.68	1534.70 ± 52.57
Glu	447.05 ± 14.68	92.96 ± 2.48	415.97 ± 22.99	2002.87 ± 13.53	134.30 ± 7.42	2038.81 ± 61.31
Ser	nd	nd	32.25 ± 11.33	119.35 ± 1.56	nd	118.37 ± 16.22
His	nd	nd	10.37 ± 1.37	11.64 ± 0.83	9.20 ± 3.33	8.58 ± 1.68
Gly	27.73 ± 1.77	15.09 ± 0.30	68.75 ± 7.24	76.96 ± 0.86	70.95 ± 7.47	112.65 ± 7.74
Thr	nd	nd	nd	58.28 ± 1.44	nd	58.61 ± 2.90
Arg	nd	nd	nd	12.32 ± 1.63	nd	nd
Ala	129.78 ± 3.29	56.53 ± 0.57	288.42 ± 11.05	1257.19 ± 6.03	134.32 ± 5.65	1318.30 ± 42.94
Tyr	nd	nd	10.35 ± 3.00	23.75 ± 5.42	nd	20.27 ± 6.17
Val	nd	6.48 ± 0.30	nd	nd	nd	nd
Met	nd	nd	32.26 ± 5.19	nd	nd	nd
Trp	nd	nd	nd	nd	nd	nd
Phe	2360.00 ± 72.43	nd	2400.69 ± 2.98	123.03 ± 2.98	4224.15 ± 22.37	103.61 ± 5.09
Ile	nd	nd	nd	nd	nd	nd
Leu	6.34 ± 0.50	19.75 ± 0.59	nd	0.99 ± 0.36	nd	nd
Lys	37.90 ± 2.03	6.87 ± 0.45	6.43 ± 3.04	11.62 ± 1.12	nd	nd
Total FAAs	3105.53 ± 55.96 C ***	197.68 ± 2.57 c	3763.99 ± 75.94 B **	4803.66 ± 21.43 b	5055.33 ± 54.45 A	5313.91 ± 193.02 a

Results are expressed as average ± standard deviation of the mean (n = 3). The abbreviation nd in the table indicates non-detected. Different letters indicate statistical differences in the amount of total FAAs extracted using multiple solvents during 1 h (uppercase letters) or 2 h (lowercase letters). The statistical differences in the amount of total FAAs extracted by using different times of extraction and the same solvent are represented as: *P < 0.05, **P < 0.01 and ***P < 0.001