Skip to main content
. 2018 Mar 1;12(2):026015. doi: 10.1088/1752-7163/aa9eef

Table 1.

List of the discriminatory volatile metabolites putatively identified, along with their importance ranks from each machine learning algorithms (RF, SVM, and PLS-DA).

RSV Rank IAV Rank
# RF PLS SVM RF PLS SVM Compound Class Formula CAS Forward similarity Reverse similarity Probability LRI exp LRI lit 1tR (min:s) 2tR (s) Reference
1 34 Unknown 467 04:02 0.8
2 9 Unknown 467 04:03 1.3
3 18 8 Unknown 468 04:04 0.8
4 16 16 6 Unknown 469 04:06 0.7
5 20 Unknown 473 04:14 0.7
6 42 22 Unknown 474 04:16 0.7
7 35 5 13 10 Unknown 475 04:18 1.2
8 20 14 Acetaldehyde Ald C2H4O 75-07-0 863 905 8534 476 04:20 0.8 [46, 47, 54]
9 12 34 11 Unknown 476 04:21 2.1
10 17 Unknown 476 04:22 0.6
11 25 19 Unknown 477 04:22 0.9
12 34 25 Unknown 477 04:23 0.7
13 17 Unknown 483 04:36 0.7
14 33 Unknown 487 04:43 0.8
15 8 29 23 Alkylated hydrocarbon Hyd 469 04:52 0.6
16 19 Unknown 478 05:07 0.7
17 33 24 Unknown 487 05:22 0.8
18 31 11 23 30 Ethanol Alc C2H6O 64-17-5 820 836 5124 500 506 05:45 1.3 [46, 51, 56]
19 21 Unknown 509 06:00 0.7
20 18 Furan Het-Cyc C4H4O 110-00-9 801 905 9424 512 511 06:05 0.9 [47]
21 4 2 2-Propenal Ald C3H4O 107-02-8 808 860 9010 519 523 06:17 1.0 [47]
22 29 Propanal Ald C3H6O 123-38-6 846 851 7605 522 526 06:23 0.8 [38, 46, 47, 52]
23 15 32 Acetone Ket C3H6O 67-64-1 965 967 9537 526 530 06:30 0.9 [33, 46, 47]
24 32 4 Unknown 529 06:35 0.9
25 6 31 20 Unknown 532 06:40 0.7
26 34 Unknown 539 06:51 0.8
27 14 Unknown 545 07:01 0.8
28 35 4 2-Propanol Alc C3H8O 67-63-0 872 910 7258 552 542 07:14 1.1 [31, 52]
29 39 8 13 1-Propanol Alc C3H8O 71-23-8 867 912 7823 553 07:16 1.1 [50, 51]
30 31 Unknown 556 07:21 0.9
31 9 2 Unknown 556 07:21 1.1
32 41 11 2-methyl-Pentane Hyd C6H14 107-83-5 923 932 7352 557 564 07:23 0.7 [46, 50–52]
33 38 Alkylated hydrocarbon Hyd 561 07:28 0.7
34 1 3-Hydroxy-3-methyl-2-butanone Ket C5H10O2 115-22-0 815 837 6977 561 07:29 1.0
35 10 Unknown 575 07:53 1.1
36 4 5 3-methyl-Pentane Hyd C6H14 96-14-0 868 878 3671 576 581 07:55 0.7 [46, 51]
37 23 24 26 2,3-dihydro-Furan Het-Cyc C4H6O 1191-99-7 844 913 5941 591 08:20 0.9 [19]
38 7 Unknown 599 08:34 0.7
39 17 13 2-Butenal Ald C4H6O 4170-30-3 819 872 5104 605 08:46 0.8 [46]
40 11 29 9 Alkylated hydrocarbons Hyd 606 08:48 0.7
41 1 17 32 n-Hexane hyd C6H14 110-54-3 911 921 8003 606 600* 08:48 0.7 [47, 50, 52]
42 40 Alkylated hydrocarbons Hyd 622 09:20 0.7
43 36 Alkylated hydrocarbons Hyd 622 09:21 0.7
44 23 10 Alkylated hydrocarbons Hyd 96-37-7 628 09:32 0.7
45 27 Disulfide, bis[1-(methylthio)ethyl] S-Com C6H14S4 69078-77-9 802 851 5684 630 09:37 1.2 [57]
46 25 3 2-Butanone Ket C4H8O 78-93-3 890 904 7723 633 09:42 0.9 [47, 50, 55]
47 15 28 Methyl-cyclopentane Hyd C6H12 96-37-7 891 905 4872 639 638 09:55 0.7 [50, 51]
48 6 34 36 Methyl sulfone S-Com C2H6O2S 67-71-0 823 832 6612 639 09:56 2.1 [49]
49 38 Formic acid, propyl ester Est C4H8O2 110-74-7 809 829 7358 647 10:10 0.9
50 5 21 Tetrahydrofuran Het-Cyc C4H8O 845 864 4102 652 655 10:18 0.8 [47]
51 11 Unknown 654 10:26 2.0
52 23 Alkylated hydrocarbons Hyd 662 10:43 0.7
53 12 Alkylated hydrocarbon Hyd 667 10:52 0.7
54 29 9 2-methyl-hexane Hyd C7H16 856 864 4872 673 674 11:05 0.7 [51]
55 18 Cyclohexane Hyd C6H12 110-82-7 849 867 1590 676 673 11:10 0.7 [51]
56 10 26 26 9 Benzene Aro C6H6 71-43-2 883 911 7847 684 684 11:28 0.9 [46, 47, 51]
57 28 Unknown 691 11:42 0.9
58 28 3-methyl-butanal Ald C5H10O 96-17-3 882 884 5914 701 694 12:02 0.8 [47, 51]
59 14 27 Alkylated hydrocarbons Hyd 731 13:13 0.7
60 27 Alkylated hydrocarbons Hyd 731 13:13 0.7
61 43 2,5-dimethyl hexane Hyd C8H18 592-13-2 802 823 3156 734 737 13:20 0.7
62 22 Alkylated hydrocarbons Hyd 755 14:10 0.7
63 24 Alkylated hydrocarbons Hyd 757 14:15 0.7
64 10 Alkylated hydrocarbons Hyd 762 14:28 0.7
65 17 2-methyl heptane Hyd C8H18 592-27-8 833 854 3824 766 767 14:36 0.7 [46]
66 16 3-methyl heptane Hyd C8H18 589-81-1 826 845 3421 774 774 14:55 0.7 [46, 51]
67 19 27 Toluene Aro C7H8 108-88-3 841 877 4083 794 795 15:42 0.9 [47, 52]
68 21 Alkylated hydrocarbon Hyd 806 16:12 0.7
69 24 19 13 Unknown 818 16:40 0.7
70 31 Alkylated hydrocarbons Hyd 821 16:47 0.7
71 26 37 Alkylated hydrocarbons Hyd 823 16:52 0.7
72 7 Alkylated hydrocarbons Hyd 830 17:07 0.7
73 40 Unknown 837 17:25 1.0
74 30 16 15 Hexanal Ald C6H12O 66-25-1 841 868 5463 840 540 17:32 0.9 [46, 47, 51]
75 18 2,4-dimethyl-Heptane Hyd C9H20 2213-23-2 852 892 3592 844 844 17:40 0.7 [47]
76 35 43 2,4-Dimethyl-1-heptene Hyd C9H20 19549-87-2 834 861 3120 847 847 17:47 0.7 [46, 48]
77 20 22 2-methyl-Octane Hyd C9H20 3221-61-2 819 893 4734 865 873 18:30 0.7 [47]
78 13 Alkylated hydrocarbons Hyd 875 18:54 0.7
79 32 Unknown 885 19:18 0.8
80 8 7 15 Ethylbenzene Aro C8H10 100-41-4 840 886 4996 890 889 19:28 0.9 [38, 51]
81 3 31 3 p-Xylene Aro C8H10 106-42-3 812 832 2691 898 897 19:48 0.9 [47, 51]
82 28 Alkylated hydrocarbons Hyd 918 20:33 0.7
83 25 o-Xylene Aro C8H10 95-47-6 815 847 2264 926 924 20:51 1.0 [31, 47, 51]
84 33 39 Styrene Aro C8H8 100-42-5 909 922 4797 928 926 20:55 1.1 [47, 51]
85 15 Alkylated hydrocarbons Hyd 930 21:00 0.7
86 27 Unknown Est C5H10O2 934 21:08 0.9
87 33 Alkylated hydrocarbons Hyd 936 21:12 0.7
88 21 Benzene, (1-methylethyl)- Aro C9H12 98-82-8 818 861 4654 953 954 21:51 0.9
89 25 Alkylated hydrocarbons Hyd 965 22:18 0.7
90 27 30 Alkylated hydrocarbons Hyd 978 22:45 0.7
91 2 33 2 Decane Hyd C10H22 124-18-5 821 853 768 1000 1000* 23:35 0.7 [47, 51]
92 30 Alkylated hydrocarbons Hyd 1014 24:05 0.7
93 26 17 Alkylated hydrocarbons Hyd 1020 24:17 0.7
94 18 14 Alkylated hydrocarbons Hyd 1024 24:25 0.7
95 14 Benzaldehyde Ald C7H6O 100-52-7 802 900 5753 1030 24:38 1.5 [31, 34, 47, 52]
96 43 Alkylated hydrocarbons Hyd 1049 25:17 0.7
97 42 35 10 Alkylated hydrocarbons Hyd 1059 25:37 0.7
98 31 Alkylated hydrocarbons Hyd 1065 25:50 0.7
99 39 Benzonitrile Aro C7H5N 100-47-0 807 837 5265 1068 1071 25:56 1.6 [34]
100 38 2-ethyl-1-hexanol Alc C8H18O 104-76-7 871 883 6374 1079 26:18 1.1 [48]
101 5 Ketone Ket 1094 26:50 0.9
102 22 7 Undecane Hyd C11H24 1120-21-4 841 868 1477 1100 1100* 27:03 0.7
103 18 21 Alkylated adehyde Ald C5H10O 1101 27:05 1.5
104 12 Alkylated hydrocarbons Hyd 1102 27:06 0.7
105 9 Alkylated hydrocarbons Hyd 1102 27:07 0.7
106 28 Alkylated hydrocarbons Hyd 1109 27:19 0.7
107 34 Alkylated hydrocarbons Hyd 1126 27:52 1.0
108 19 16 Alkylated hydrocarbon Hyd 1126 27:53 0.6
109 8 Unknown 1128 27:57 0.9
110 5 6 Unknown 1142 28:25 1.4
111 4 Nonanal Ald C9H18O 124-19-6 846 839 5616 1150 1147* 28:40 0.9 [47, 49, 52, 53]
112 7 12 16 19 3 Dodecane Hyd C12H26 112-40-3 836 859 788 1200 1200* 30:17 0.7 [38]
113 30 Unknown 1219 30:52 0.6
114 12 Alkylated hydrocarbons Hyd 1214 30:43 0.7
115 22 Alkylated hydrocarbons Hyd 1246 31:39 0.7
116 32 Alkylated hydrocarbons Hyd 1251 31:50 0.7
117 12 Unknown 1256 31:59 0.7
118 6 Unknown 1261 32:07 0.8
119 11 41 25 Alkylated hydrocarbons Hyd 1265 32:15 0.7
120 42 Unknown 1275 32:32 0.7
121 13 Alkylated benzene Hyd C14H22 1280 32:42 0.8 [51]
122 37 37 35 Alkylated hydrocarbons Hyd 1281 32:44 0.7
123 15 Alkylated hydrocarbons Hyd 1309 33:33 0.7
124 20 40 Alkylated hydrocarbons Hyd 1327 34:04 0.7
125 1 20 26 Alkylated hydrocarbons Hyd 1327 34:04 0.7
126 2 4 Tetradecane Hyd C14H30 629-59-4 840 864 3120 1400 1400* 36:09 0.7
127 3 28 1 Alkylated hydrocarbons Hyd 1401 36:09 0.7
128 35 14 Alkylated hydrocarbons Hyd 1411 36:25 0.7
129 24 Unknown 1454 37:34 0.9
130 3 5 2 Pentadecane Hyd C15H32 629-62-9 844 859 1010 1500 1500* 38:48 0.7
131 23 Unknown 1552 40:09 0.9
132 41 29 Alkylated hydrocarbons Hyd 1554 40:12 0.7
133 21 36 6 Unknown 1591 41:08 1.6
134 1 1 7 Hexadecane Hyd C16H34 544-76-3 819 828 1520 1601 1600* 41:24 0.8
135 22 Unknown 1636 42:15 0.7
136 30 8 33 Alkylated hydrocarbons Hyd 1642 42:23 0.7
137 32 Unknown 1701 43:50 0.9
138 24 29 Unknown 1715 44:10 0.9