Table 1.

Metabolites varying significantly in human saliva (female donors), during storage at 22 °C and 4 °C, up to 48 h. Only metabolites with |ES| > ES_error and p-values < 0.05 were considered. ^a overlapped resonances may contribute slightly to variations in this peak; ^b metabolites varying at both temperatures, although not necessarily in the same direction; NAG, N-acetyl of glycoproteins; SCFA, short chain fatty acids; Ui, unassigned resonance i ordered by chemical shift; r²: correlation coefficient. Chemical shifts shown in the second column correspond to the peaks used for integration.

T (°C)	Metabolite (δ H/ppm, Multiplicity)	6 h vs. 0 h		8 h vs. 0 h		12 h vs. 0 h		24 h vs. 0 h			48 h vs. 0 h	Correlation
		Effect Size	p-Value	Effect Size	p-Value	Effect Size	p-Value	Effect Size	p-Value	Effect Size	p-Value	r 2	p-Value
22 °C	Amino acids
	alanine (1.48, d)	-	-	-	-	−1.62 ± 1.33	7.92 × 10−3	−1.90 ± 1.39	1.6 × 10−2	−1.82 ± 1.38	3.2 × 10−2	−0.66	4.2 × 10−6
	betaine (3.26, s)	-	-	-	-	-	-	-	-	−1.51 ± 1.30	3.3 × 10−2	−0.58	9.5 × 10−5
	sarcosine a (2.74, s)	-	-	-	-	-	-	-	-	−1.67 ± 1.34	7.9 × 10−3	−0.56	1.8 × 10−4
	SCFA
	acetate (1.92, s)	-	-	-	-	-	-	-	-	1.57 ± 1.31	2.6 × 10−2	0.52	5.9 × 10−4
	Organic acids
	lactate (4.11, q)	-	-	−1.33 ± 1.26	3.22 × 10−2	−1.75 ± 1.36	3.3 × 10−2	−2.07 ± 1.44	7.9 × 10−3	−2.53 ± 1.56	7.9 × 10−3	−0.64	8.1 × 10−6
	pyruvate a (2.38, s)	-	-	-	-	-	-	−1.41 ± 1.28	3.2 × 10−2	−1.70 ± 1.35	1.6 × 10−2	−0.58	8.7 × 10−5
	Carbohydrates
	galactose (5.27, d)	-	-	-	-	-	-	−1.67 ± 1.34	3.2 × 10−2	−2.05 ± 1.44	7.9 × 10−3	−0.50	1.0 × 10−3
	Other compounds
	choline (3.20, s)	-	-	-	-	-	-	-	-	−2.04 ± 1.43	3.2 × 10−2	−0.49	1.5 × 10−3
	hypoxanthine (8.19, s)	-	-	-	-	-	-	−1.44 ± 1.43	3.2 × 10−2	-		−0.47	2.2 × 10−3
	NAG a (2.06, s)	-	--	-	-	-		-	-	−1.85 ± 1.38	3.2 × 10−2	−0.55	2.0 × 10−4
	Unassigned resonances
	U1 (0.75, br)	−1.62 ± 1.33	3.2 × 10−2	−1.73 ± 1.35	3.2 × 10−2	−1.41 ± 1.28	3.2 × 10−2	−2.50 ± 1.57	7.9 × 10−3	−2.80 ± 1.66	7.9 × 10−3	−0.66	3.5 × 10−6
	U3 (3.22, s)	-		-	-	-	-	-		−1.60 ± 1.32	1.6 × 10−2	−0.50	9.0 × 10−4
4 °C	Amino acids
	glycine (3.56, s)	-	-	-	-	-	-	-	-	1.33 ± 1.14	3.5 × 10−2	0.46	5.1 × 10−4
	tyrosine (6.90, d)	-	-	-	-	-	-	1.79 ± 1.23	1.4 × 10−2	1.97 ± 1.27	4.7 × 10−3	0.57	7.3 × 10−6
	SCFA
	butyrate (1.55, q)	-	-	-	-	-	-	-	-	−1.23 ± 1.12	4.8 × 10−2	−0.43	1.3 × 10−3
	Carbohydrates
	galactose b (5.27, d)	-	-	-	-	-	-	-	-	1.99 ± 1.27	8.2 × 10−3	0.46	5.9 × 10−4
	xylose (5.21, d)	1.26 ± 1.16	4.1 × 10−2	-	-	-	-	-	-	1.48 ± 1.16	2.2 × 10−2	0.45	6.7 × 10−4
	Other compounds
	hypoxanthine b (8.19, s)	-	-	-		-	-	-	-	1.13 ± 1.10	3.5 × 10−2	0.34	1.4 × 10−2
	Unassigned resonances
	U1 b (0.75, br)	-	-	-	-	-	-	-	-	−2.18 ± 1.32	4.7 × 10−3	−0.57	8.3 × 10−6
	U2 (0.84, s)	-	-	-	-	-	-	-	-	−1.54 ± 1.17	2.2 × 10−2	−0.40	2.7 × 10−3