Table 2.

Free amino acids and crude protein content in the mushroom cultivation substrates used.

Amino acid	Abbreviation	WS	GM	OL
Alanine	Ala	0.003 ± 0.001 a	0.065 ± 0.007 c	0.023 ± 0.005 b
Glycine	Gly	0.002 ± 0.001 a	0.022 ± 0.004 c	0.009 ± 0.000 b
Valine	Val	0.002 ± 0.001 a	0.010 ± 0.002 b	0.004 ± 0.000 a
Leucine	Leu	0.008 ± 0.005 a	0.032 ± 0.006 b	0.008 ± 0.001 a
Isoleucine	Ile	0.004 ± 0.002 a	0.019 ± 0.004 b	0.006 ± 0.001 a
Threonine	Thr	0.004 ± 0.002 a	0.020 ± 0.005 b	0.006 ± 0.000 a
Serine	Ser	0.005 ± 0.002 a	0.043 ± 0.003 c	0.012 ± 0.001 b
Proline	Pro	0.004 ± 0.001 a	0.091 ± 0.020 b	0.022 ± 0.001 a
Asparagine	Asn	0.003 ± 0.001 a	0.137 ± 0.002 c	0.061 ± 0.015 b
Thioproline	Thp	0.013 ± 0.005 a	0.105 ± 0.003 c	0.147 ± 0.004 b
Aspartic acid	Asp	0.012 ± 0.003 a	0.097 ± 0.006 c	0.138 ± 0.003 b
Methionine	Met	0.003 ± 0.002 a	0.001 ± 0.001 a	nd
Hydroxyproline	Hyp	nd	0.003 ± 0.001	nd
Glutamic acid	Glu	0.155 ± 0.026 a	0.204 ± 0.002 c	0.064 ± 0.002 b
Phenylalanine	Phe	0.006 ± 0.003 a	0.024 ± 0.005 b	0.006 ± 0.000 a
Glutamine	Gln	0.037 ± 0.010 a	0.093 ± 0.003 b	0.037 ± 0.004 a
Ornithine	Orn	0.022 ± 0.000 a	0.025 ± 0.001 b	0.022 ± 0.000 a
Lysine	Lys	0.033 ± 0.001 a	0.057 ± 0.006 b	0.035 ± 0.001 a
Histidine	His	0.0003 ± 0.000 a	0.023 ± 0.005 b	0.002 ± 0.000 a
Tyrosine	Tyr	0.006 ± 0.002 a	0.018 ± 0.003 b	0.008 ± 0.001 a
Tryptophan	Trp	0.001 ± 0.001 a	0.085 ± 0.001 b	0.093 ± 0.009 b
γ-Aminobutyric acid	GABA	nd	0.058 ± 0.003 a	0.008 ± 0.002 b
Sum of amino acids		0.319 ± 0.070	1.231 ± 0.077	0.711 ± 0.033
Crude protein		85.20 ± 4.34 a	116.60 ± 5.04 b	131.12 ± 0.09 c

Values (mg/g dry weight) represent the means ± SD (n = 3). Lack of letters in common indicates statistically significant differences (Duncan’s t-Test. p < 0.05) in comparisons of treatment means between different substrates. Abbreviations: WS, wheat straw; GM, wheat straw with grape marc (1:1 w/w ratio); OL, olive leaves with olive mill wastes (3:1 w/w); nd, not detected.