Table 2. Representative Metabolites Associated with the Nicotine Degradation and d-Glucuronate Degradation Pathways in Multimodal Pathway Analysis.

pathway/metabolite	METLIN ID	dysregulationa	fold change	p-value	m/z	tR (min)	adduct type
Nicotine Degradation V
3-pyridylacetate	NA	down	2.1	4.50 × 10–3	121.0279	12.9	[M – NH3 + H]+1
4-(3-pyridyl)-butanoate	NA	up	1.7	6.60 × 10–3	166.0855	13.7	[M + H]+1
cotinine-gluc	NA	down	1.5	7.20 × 10–3	373.1022	14.6	[M + Na – 2H]−1
cotinine methonium ion	NA	down	1.5	5.00 × 10–3	209.1516	18.8	[M + NH3 + H]+1
trans-3-hydroxycotinine-gluc	NA	down	2.1	6.00 × 10–3	196.0593	12.8	[M + H + Na]+2
Nicotine Degradation IV
3-pyridylacetate	NA	down	2.1	4.50 × 10–3	121.0279	12.9	[M – NH3 + H]+1
4-(3-pyridyl)-butanoate	NA	up	1.7	6.60 × 10–3	166.0855	13.7	[M + H]+1
d-Glucuronate Degradation Pathway
l-xylulose	139	down	2.2	3.00 × 10–3	151.0604	9.1	[M + H]+1
l-gulonate	63,144	down	2.4	2.40 × 10–3	197.0652	12.3	[M + H]+1
l-gulonate	63,144	down	3	1.50 × 10–4	195.0503	12.0	[M – H]−1
aldehydo-d-glucuronate	NA	down	2	1.70 × 10–3	177.0392	13.2	[M – H2O + H]+1
3-keto-l-gulonate	58,394	down	2	1.70 × 10–3	177.0392	13.2	[M – H2O + H]+1

^aDysregulation (fold change) relative to whites; NA: not applicable.