Table 3.

Putatively annotated and identified metabolites

	Ion description	Detected m/z	Predicted formula	Δmass ppm	RT (min)	RSD QC (%)	P	q	Ratio	Area fold change	ID level
N-Phenylacetylglutamine	[M + Na] + 1	287.09982	C13 H16 N2 O4	− 1.13	2.89	5	0.004	0.040	9.238	3.21	2
20 β-Dihydrocortisol	[M + H] + 1	365.23218	C21 H32 O5	0.20	5.31	4	0.018	0.098	8.150	3.03	2
Cortisol	[M + Na] + 1	385.19824	C21 H30 O5	0.57	10.05	7	< 0.001	0.007	0.170	− 2.55	2
Indole-3-carboxaldehyde	[M + H] + 1	146.06001	C9 H7 N O	0.25	5.28	4	< 0.001	0.001	0.018	− 5.83	2
Eicosatetraynoic acid	[M + H] + 1	297.18481	C20 H24 O2	0.15	4.74	11	0.005	0.051	0.072	− 3.79	2
trans-3-Indoleacrylic acid	[M + H] + 1	188.07047	C11 H9 N O2	0.72	5.28	4	< 0.001	< 0.001	0.002	− 9.04	2
Glycocholic acid	[M + Na] + 1	88.29858	C26 H43 N O6	0.23	14.61	5	0.042	0.150	10.866	3.44	1
Kynurenic acid	[M + H] + 1	190.04984	C10 H7 N O3	0.37	2.58	0.4	0.004	0.047	9.895	3.31	1
N-Acetyl-DL-tryptophan	[M + H] + 1 [2M − H] − 1	247.10748	C13 H14 N2 O3	1.10	5.28	3	< 0.001	< 0.001	0.001	− 10.73	1
		491.19403		0.05	5.28	27
D-(+)-Tryptophan	[M + H − NH3] + 1	188.07047	C11 H12 N2 O2	0.67	5.28	1	< 0.001	< 0.001	0.001	− 10.35	1
5-hydroxy-L-tryptophan	[M + H] + 1	221.09193	C11 H12 N2 O3	0.42	1.25	0.4	0.011	0.076	8.856	3.15	1
Kynurenine	[M + H] + 1	209.09212	C10 H12 N2 O3	0.09	1.31	0.5	0.072	0.190	2.685	1.42	1
3-hydroxy-L-kynurenine	[M + H + MeOH] + 1	257.11285	C10 H12 N2 O4	1.42	1.07	2	0.007	0.062	4.450	2.15	2

Ratio = pre/post

Putatively annotated (Level 2) and identified metabolites (Level 1). Univariate analysis (t-test) between groups. Bold font indicates metabolites that have passed the defined level of significance (p < 0.05). Area fold change is expressed as log2 scale