Table 1. Compounds identified through PTR-Analysis.

Compound sa	Measured, m/zb	Protonated chemical formulac	Chemical and functional grouping cd	Tentative of identificationse	Theoretical, m/zf	Compound classificationg	PTR-TOF citationsh	Tuber magnatum citationsi	Tuberspp. Citationsl	bVOCs citationsm
1	27.025	C2H3+	H1	Acetylene	27.0229	O				46
2	29.039	C2H5+	H2	Alkyl fragment (ethanol)	29.0386	O	21
3	31.042	CH3O+	O1	Formaldheyde	31.0178	X				46
4	33.033	CH5O+	O2	Methanol	33.0335	X	21,26	18	27
5	34.995	H3S+	S1	Hydrogen sulfide	34.9949	X	21			44,51
6	41.039	C3H5 +	H3	Alkyl fragment	41.0385	X	20,21,26
7	42.034	C2H4N+	O3	Acetonitrile	42.0338	X	21,26
8	43.018	C2H3O+	O4	Alkyl fragment (ethenone)	43.0178	X	26
9	43.054	C3H7+	H4	Alkyl fragment (propene)	43.0542	X	26			46
10	45.033	C2H5O+	O5	Acetaldehyde	45.0334	X	21,26	18	12,14,15,46,47
11	46.990	CH3S+	S2	Methanethial	46.9949	O				48
12	47.013	CH3O2+	O6	Formic acid	47.0128	O	21,26			46
13	47.049	C2H7O+	O7	Ethanol	47.0491	X	21,26	10,12,18,49		14,46,47,50
14	49.011	CH5S+	S3	Methanethiol	49.0106	X	21,26	5,10,18		46,47,51
15	53.038	C4H5+	H5	Cyclobutadiene	53.0385	O				52,53
16	55.054	C4H7+	H6	Alkyl fragment	55.0542	X	26
17	57.034	C3H5O+	O8	2-Propenal (Acrolein)	57.0334	O	21			54
18	57.068	C4H9+	H7	1-Butene (alkyl fragment)	57.0699	X	21			55
19	59.049	C3H7O+	O9	2-Propanone (acetone)	59.0491	X	21,26	10,12	14,15	46,47,56,57
20	61.028	C2H5O2 +	O10	Acetic acid	61.0284	X	21,26	49	12,15	46,47,58,59,60
21	63.026	C2H7S+	S4	Dimethyl sulfide	63.0262	X	21,26	5,10,12,18,49	14,15,16,17	46,51
22	65.023	CH5O3+	O11	Methanetriol	65.0233	O				61
23	67.054	C5H7+	H8	3-Penten-1-yne	67.0542	X			62
24	68.05	C4H6N+	O12	Pyrrole	68.0494	X	20	10,11
25	69.033	C4H5O+	T1	Furan	69.0336	X	20		63
26	69.070	C5H9+	T2	2-Methyl-1,3- butadiene (isoprene)	69.0698	X	21		12	51,56
27	71.049	C4H7O+	O13	3-Buten-2-one	71.0491	X		10
28	71.086	C5H11+	H9	Alkyl fragment (several compounds)	71.0855	O	20,26
29	73.03	C3H5O2+	O14	Acrylic Acid	73.0284	X			15
30	73.065	C4H9O+	O15	2-Butanone	73.0648	X	21,26		12,14,15,17,27	64
31	74.061	C3H8NO+	O16	Dimethylformamide	74.0610	O				65
32	75.044	C3H7O2+	O17	Methyl acetate	75.0441	X	21		14
33	75.080	C4H11O+	O18	2-Methyl-1-propanol (isobutanol)	75.0804	X			12,27	46,51,56,60,64
34	77.01	C3H9S+	S5	1-Propanethiol	77.0055	O				55
35	78.046	C2H6OS+	S6	(Methylsulfinyl)methanide	78.0133	O				45
36	79.021	C2H7OS+	S7	Dimethyl sulfoxide (Sulfinylbismethane)	79.0212	X		18
37	80.049	C5H6N+	O19	Pyridine	80.0494	X	20		27
38	81.000	CH5S2+	S8	Bis(methylthio) methane	80.9827	X		10
39	81.069	C6H9+	H10	Alkyl fragment (hexenals/hexenols/terpenoids)	81.0699	X	21,25,26
40	82.06	C6H10+	H11	Cyclopentenyl carbenium	82.0777	#
41	83.049	C5H7O+	T3	2-Methylfuran	83.0491	X	20	10	12	51
42	85.029	C4H5O2+	T4	5 h-Furan-2-one	85.0284	X			27
43	86.018	C4H6S+	S9	Thiophenium	86.0184	O				66
44	87.043	C4H7O2+	O20	Butan-4-olide	87.0441	X			15	51
45	87.081	C5H11O+	O21	2-Methylbutanal	87.0804	X		12	15,17	46
46	88.030	C4H8S+	S10	3,4-Dihydro-2H-thiophene	88.0341	O				66
47	89.041	C4H9S+	S11	Allyl methyl sulfide	89.0419	X		5,9	12
48	89.056	C4H9O2+	O22	3-Hydroxy-2-butanone (acetoin)	89.0597	X	21		15,27	46,50,51,60,67
49	91.055	C4H11O2+	O23	2-3-Butanediol	91.0753	X			12,27	46,51,67
50	93.035	C3H9OS+	S12	2-Methylmercaptoethanol	93.0368	O				51,68
51	93.068	C7H9+	AH1	Methylbenzene (toluene)	93.0698	X	21		12,15,69	55
52	95.010	C2H7O2S+	S13	Dimethyl sulfone	95.0035	X	20,26	10,18
53	97.025	C5H5O2 +	T5	Furfural (2-Furancarboxaldehyde)	97.0284	X	25		15	46,67
54	97.065	C6H9O+	T6	2,4-Dimethylfuran	97.0647	X	20	10
55	99.044	C5H7O2+	T7	4-Methyl-5 h-furan-2-one	99.080	X	20		27
56	101.045	C5H9S+	S14	2-Methyl-4,5-dihydrothiophene	101.0419	X	20		13,27
57	101.060	C5H9O2 +	O24	2,3-Pentanedione	101.0597	X	21,26	10
58	103.050	C8H7+	AH2	Ethynylbenzene	103.0543	X			12,62
59	103.076	C5H11O2+	O25	4-Hydroxy-3-methyl-2-butanone	103.0754	X			14
60	105.037	C4H9OS+	S15	Methional	105.0368	X		5	16,27	51
61	105.060	C4H9O3+	O26	4-Hydroxybutanoic acid	105.0546	X		10
62	106.995	C3H7O2S+	S16	2-Methylthioacetic acid	107.0161	X		5
63	107.086	C8H1 1 +	AH3	1,3-Dimethylbenzene terpenes fragment	107.0855	X	21		15
64	109.010	C6H5S+	S17	2-Ethynylthiophene	109.0106	#
65	109.065	C7H9O+	P1	Anisole	109.0647	X			12,15
66	111.044	C6H7O2+	T8	2-Acetylfuran	111.0431	O	20			51,70
67	111.104	C8H15+	T9	4-Methyl-1,3-heptadiene	111.1168	X			27
68	113.040	C6H9S	S18	2,5-Dimethylthiophene	113.0419	#
69	113.100	C7H13O+	T10	2-Heptenal	113.0960	X			15
70	115.020	C5H7OS+	S19	2-Methyl-3-furanthiol	115.0212	X			16
71	115.075	C6H11O2+	P2	3,5-Dimethyldiidro-2(3 h)-furanone	115.0746	X	20	10		51
72	117.078	C6H13S+	S20	Cyclopentyl-1-thiaethane (methylsulfanyl cyclopentane)	117.0732	X			27
73	119.06	C6H15S+	S21	1-(Methylthio)pentane	119.0385	X		5
74	121.065	C5H13OS+	S22	2-Hydroxyethyl propyl sulfide	121.0681	X		5
75	121.101	C9H1 3+	AH4	1,2,4-Trimethylbenzene	121.0647	X			15
76	123.045	C4H11O2S+	S23	Diethanol sulfide	123.0474	X		5
77	123.080	C8H11O+	P3	1-Methoxy-3-methylbenzene	123.0804	X			12,14,15,27
78	125.010	C3H9OS2+	S24	(Methylsulfinyl)(methylthio)methane	125.0089	X		5
79	125.096	C8H13O+	T11	2-Butylfuran	125.0961	X	26	10
80	127.035	C6H7O3+	T12	Methyl 2-Furancarboxylate	127.0389	O				51,71,72
81	127.112	C8H15O+	O27	1-Octen-3-one	127.1117	X	26	10
82	129.070	C10H9+	AH5	Naphthalene	129.0698	X			15	50
83	129.127	C8H17O+	T13	c8 aldehydes and ketones (2-octanone)	129.1273	X	26	10
84	131.085	C7H15S+	S25	Methylsulfanylcyclohexane	131.0888	X			27
85	131.107	C7H15O2+	O28	Ethyl 2- methylbutanoate (Ethyl 2-methylbutyrate)	131.1066	X			12,14,27
86	133.101	C10H13+	T14	p-Cymenene	133.1011	X		10
87	135.117	C10H15+	T15	p-Cymene	135.1168	X		5,18
88	137.134	C10H17+	T16	Terpenes (Limonene)	137.1325	X	26	5,10,18,49
89	139.148	C9H15O+	T17	2-Pentylfuran	139.1117	X		10	12,15	50
90	141.130	C9H17O+	T18	3-Nonen-2-one (several compounds)	141.1273	X		10
91	143.144	C9H19O+	O29	Nonanal	143.1430	X	20,26	10		73
92	143.107	C8H15O2+	O30	2,3-Octanedione	143.066	X	26,30		15
93	145.076	C10H9O+	T19	3-Phenyl-furan	145.043	X			27
94	147.120	C8H19S+	S26	2-Ethyl-1-hexanethiol	147.1201	X		5
95	149.130	C11H17+	AH6	(1-Ethylpropyl)benzene	149.1324	X			27
96	151.065	C6H15S2+	S27	Methyl pentyl disulfide	151.0609	X		5
97	153.130	C10H17O+	T20	2-Methyl-5-(1-methylethenyl)-2-cyclohexen-1-ol (Carveol)	153.1273	X	25	5
98	155.010	C4H11S3+	S28	Diethyl trisulfide	155.0017	X		5
99	157.159	C10H21O+	O31	Decanal	157.1586	X	22	10
100	159.140	C9H19O2+	O32	2-Methylbutyl 2-methylpropanoate	159.1379	X			12,27
101	161.155	C9H21O2+	O33	1,9-Nonanediol	161.1536	O				55,74
102	163.075	C11H1 5O+	O34	3-Methyl-2-(penta-2,4-dienyl)cyclopent-2-enone	163.0753	X			75
103	167.140	C11H1 9O+	T21	2-Heptylfuran	167.1430	X		10		50
104	169.085	C9H13O3+	P4	1,2,4-Trimethoxybenzene	169.0859	O			12
105	171.080	C12H1 1 O+	O35	2-Undecanone	171.0804	X		10
106	175.010	C6H7O4S+	S29	4-Hydroxybenzenesulfonic acid	175.0059	X		5
107	187.11	C13H1 5O+	P5	2-Hydroxy-4-isopropylnaphthalene	187.1117	X			27
108	195.180	C13H23O+	T22	6,10-Dimethyl-5,9-undecadien-2-one (geranylacetone)	195.1743	X			17,75,76
109	197.050	C7H17S3+	S30	Methyl(methylthio)methyl Disulfide	197.0486	X		5		77
110	205.195	C15H25+	T23	Sesquiterpenes	205.195	X	25	5
111	223.200	C15H27O+	T24	Cedrol	223.2056	X		5

^aCompound rank.

^bMass to charge ratio measured by the Mass Spectrometer.

^cCompound’s Chemical formula (H⁺ added by protonation).

^dCompound classification based on their chemical and biochemical properties: AH aromatic hydrocarbon, H hydrocarbon, P phenol, S sulfur compound, T terpene, O others.

^ePutative identifications according to spectral properties.

^fTheoretical mass to charge ratio found in literature or PTR-TOF-MS manual.

^gCompounds were marked related to their bibliography, X = Previously published in Tuber magnatum or Tuber spp., O = Similar signal properties to previously published compounds, # = Signals not previously reported.

^hPTR-TOF-MS articles where molecule was reported.

ⁱT. magnatum citations of molecule.

^lTuber spp. citation of that article.

^mbiological Volatile Organic Compounds (bVOC) previously reported.