. 2021 May 11;10(5):1055. doi: 10.3390/foods10051055

Table 2.

Volatile compounds identified in the headspace of four Brassicales species analysed by HS-SPME GC-MS.

Compound Number	Compound	PubChem ID	LRI ^a		ID ^b	Peak Areas (% of total)				References
Compound Number	Compound	PubChem ID	HP-5MS	Stabilwax	ID ^b	Salad Rocket	Wasabi	Horseradish	Watercress	References
	Sulphur-containing compounds
1	carbon disulphide	6348	<600	738	B	0.43 *	0.04 *	0.02	0.11 *	[21]
2	methyl thiocyanate	11168	711	1266	B	0.13	nd	nd	0.48	[12]
3	isopropyl ITC	75263	835	1176	B	nd	4.07	0.03	nd	[7,23]
4	allyl thiocyanate	69816	870	1358	B	nd	0.48 *	0.73	nd	[22]
5	allyl ITC ^	5971	881	1371	B	nd	8.61	7.35	nd	[7,14,18,24]
6	allyl ITC ^	5971	890	1392	B	nd	52.11	39.34	nd	[7,14,18,24]
7	cyclopropane ITC	92463	899	1223	B	nd	0.07 *	0.05 *	nd	-
8	cyclopentyl-1-thiaethane	138938	922	1068	B	nd	nd	nd	0.51 *	-
9	sec-butyl ITC	78151	933	1265	B	0.46 *	4.95	1.84	nd	[7,23]
10	isobutyl ITC	68960	955	1316	B	nd	1.80	0.45	nd	[7,21]
11	3-butenyl ITC	76922	982	1455	B	0.19	4.24	1.52	nd	[3,7,22]
12	butyl ITC	11613	998	1597	B	0.67	0.12	0.32	nd	[7,15]
13	isoamyl ITC	79086	1059	1431	B	0.10	0.41 *	0.55	0.07	[3,18,22]
14	4-pentenyl ITC	87436	1086	1543	B	nd	12.42	2.26	nd	[7,22]
15	pentyl ITC	69415	1098	1488	B	0.56 *	0.12 *	0.20	nd	[21]
16	1-isothiocyanato-4-methylpentane	519452	1162	1522	B	4.96	0.01 *	0.04	0.18	[3,18,21]
17	cyclohexyl ITC	14289	1177	1650	B	nd	0.01 *	nd	nd	-
18	<unidentified ITC>	-	1193			nd	8.57	nd	nd	-
19	ibervirin	62351	1315	1991	B	0.58	0.29	1.02	nd	[3,7,22]
20	sativin	85704368	1353	>2000	B	0.55	nd	nd	nd	[12]
21	octyl ITC	78161	1372	1760	B	nd	nd	nd	0.16 *	-
22	benzyl ITC	2346	1372	>2000	B	nd	0.03 *	1.14	nd	[12,22]
23	erucin	78160	1440	>2000	B	7.16	0.01	0.02	nd	[7,12,22]
24	phenethyl ITC	16741	1477	>2000	B	nd	0.68	32.47	30.72	[7,12,18,24]
	Total sulphur-containing compounds					15.79	99.07	89.78	32.92
	Alcohols
25	1-penten-3-ol	12020	678	1159	A	0.78	nd	0.10 *	8.06	[3,7,18]
26	pentan-1-ol	6276	763	1251	A	0.13 *	0.02 *	0.02 *	0.25 *	-
27	(E)-2-penten-1-ol	5364919	763	1312	A	0.17 *	nd	nd	0.31 *	-
28	(Z)-2-penten-1-ol	15306	767	1322	A	0.76	nd	0.06	4.78	[3,22]
29	1-propoxy-2-propanol	15286	840		B	nd	nd	nd	0.24 *	-
30	(E)-3-hexen-1-ol	5284503	850	1365	A	nd	nd	nd	0.20	[3,19,22]
31	(Z)-3-hexen-1-ol	5281167	856	1387	A	40.88	nd	1.88	35.99	[3,18,22]
32	2-hexen-1-ol	5318042	863	1405	A	1.25	nd	nd	0.35	[7,13,18,22]
33	hexan-1-ol	8103	866	1355	A	4.82 *	nd	0.22	2.61	[7,18]
34	1-octen-3-ol	18827	977		A	0.18	0.01 *	0.02 *	0.06 *	[14]
35	2-ethylhexanol	7720	1025	1501	B	0.12 *	0.01 *	nd	0.12 *	-
36	benzyl alcohol	244	1035		A	nd	nd	0.05 *	nd	-
37	2-phenylethanol	6054	1116	1930	A	0.16 *	nd	0.03 *	2.64 *	-
38	1-nonanol	8914	1167		A	nd	0.03 *	nd	nd	-
39	terpinen-4-ol	11230	1182		A	nd	0.01 *	nd	nd	-
Total alcohols						49.25	0.09	2.38	55.62
	Aldehydes
40	2-pentanal	7895	699		A	nd	0.02 *	nd	nd	-
41	2-pentenal	5364752	753	1136	A	0.31	nd	0.02 *	0.23 *	[3]
42	3-hexenal	643139	796	1178	A	1.72	nd	0.04	0.23	[3,18,22]
43	hexanal	6184	798	1094	A	8.64	<0.01 *	0.37	1.16 *	[12,21]
44	(E)-2-hexenal	5281168	852	1224	A	14.30	nd	0.31	2.10	[3,7,18,21]
45	4-heptenal	5283318	901		A	0.08 *	nd	nd	0.51	-
46	heptanal	8130	902		A	0.13	nd	0.02	0.10 *	[13,21]
47	2,4-hexadienal	637564	908		B	0.09	nd	0.01 *	nd	[3,18]
48	benzaldehyde	240	964	1654	A	0.17	0.02 *	nd	nd	[12,22]
49	2,4-heptadienal (isomer 1)	5283321	994		B	0.09	nd	nd	nd	[12]
50	octanal	454	1001		A	nd	0.02 *	nd	nd	-
51	2,4-heptadienal (isomer 2)	5283324	1009	1472	B	0.15	nd	0.25 *	0.10 *	[12]
52	phenylacetaldehyde	998	1047		A	nd	nd	0.02	0.24 *	[22]
53	2-octenal	5283324	1058		A	nd	nd	0.06 *	nd	-
54	nonanal	31289	1101		A	0.41	0.10 *	0.04	0.31 *	[13,21]
55	decanal	8175	1202		A	nd	0.12 *	0.04	0.19 *	[21]
56	vanillin	1183	1403		A	0.02	nd	0.01 *	nd	[13]
Total aldehydes						26.11	0.28	1.25	5.17
	Esters
57	(Z)-pent-2-en-1-yl acetate	5363400	910		B	nd	nd	nd	0.07 *	-
58	3-hexenyl acetate	5352557	1003	1284	A	2.54	nd	nd	0.50	[14,18]
59	(Z)-3-hexenyl butanoate	5352438	1181	1440	A	0.99	nd	nd	nd	[14]
60	methyl salicylate	4133	1201		A	nd	nd	0.04 *	nd	-
61	ethyl decanoate	8048	1389		A	0.06 *	nd	0.03 *	nd	-
62	methyl dodecanoate	8139	1521		B	0.04	0.01 *	0.02 *	0.08 *	[14]
63	diethyl phthalate	6781	1588		B	0.08 *	nd	nd	nd	-
64	ethyl laurate	7800	1591		B	nd	nd	0.06 *	nd	-
Total esters						3.71	0.01	0.15	0.65
	Ketones
65	ethyl vinyl ketone	15394	682	1035	A	0.43	nd	0.05 *	nd	[3]
66	3-pentanone	7288	697	993	A	0.66	nd	0.05 *	1.86	[3,19]
67	2,3-octanedione	11449	980		A	nd	nd	0.01	nd	[22]
68	6-methyl-5-hepten-2-one	9862	983		A	0.55	nd	nd	0.23 *	[12]
69	2,2,6-trimethylcyclohexanone	17000	1038		B	nd	nd	nd	0.11 *	-
70	(E,E)-3,5-octadien-2-one	5352876	1070		B	nd	nd	0.08 *	nd	-
71	3,5-octadien-2-one	5352876	1092		B	nd	nd	0.09 *	nd	-
72	dihydro-2H-thiopyran-3(4H)-one	140474	1160	1856	B	0.58	nd	nd	nd	-
73	geranylacetone	1549778	1451		A	0.10 *	0.02 *	nd	nd	-
Total ketones						2.32	0.02	0.27	2.21
	Nitriles
74	3-butenenitrile	8009	654		B	nd	0.15	0.37	nd	[7,21]
75	5-methylhexanenitrile	29593	943		B	0.27	nd	nd	nd	[13]
76	6-heptenenitrile	4140856	971		B	nd	0.08 *	nd	nd	-
77	thiiraneacetonitrile	148821	1004		B	nd	nd	3.58 *	nd	[39]
78	phenylacetonitrile	8794	1142		B	nd	nd	0.01 *	nd	-
79	5-(methylsulfanyl)pentanenitrile	93320	1200		B	1.13	nd	nd	nd	[12]
80	4-(methylthio)-butanenitrile	100962	1213		B	nd	nd	0.11 *	nd	-
81	benzenepropanenitrile	12581	1243	>2000	B	nd	nd	0.75	1.47	[17,22]
82	<unidentified nitrile>	-	1559		B	nd	0.22	nd	nd	-
Total nitriles						1.39	0.45	4.83	1.47
	Hydrocarbons
83	2,2,4,6,6-pentamethylheptane	26058	991	947	A	nd	nd	nd	0.69 *	-
84	undecane	14257	1096		A	0.23	nd	0.01 *	nd	[15]
85	1-dodecene	8183	1187		A	nd	0.06 *	0.12 *	0.64 *	-
86	dodecane	8182	1196		A	nd	nd	0.01	nd	[22]
87	tridecane	12388	1296		A	nd	nd	0.03	nd	[22]
88	tetradecane	12389	1396		A	0.10	0.01 *	0.06 *	nd	[15]
89	pentadecane	12391	1497		A	nd	nd	0.09 *	nd	-
90	hexadecane	11006	1599		A	nd	nd	0.10 *	nd	-
91	heptadecane	12398	1699		A	nd	nd	0.06 *	nd	-
92	octadecane	11635	1799		A	nd	nd	0.03 *	nd	-
93	nonadecane	12401	1899		A	nd	nd	0.01 *	nd	-
Total hydrocarbons						0.39	0.06	0.62	1.33
	Terpenes
94	p-cymene	7463	1023	1250	A	nd	<0.01 *	0.01 *	0.06	[18]
95	o-cymene	10703	1027		A	0.12 *	0.01 *	nd	nd	-
96	d-limonene	440917	1033	1169	A	nd	<0.01 *	0.07 *	nd	-
97	eucalyptol	2758	1037		A	nd	<0.01 *	nd	nd	-
98	β-ionone	638014	1494	1952	A	0.16	nd	nd	0.43	[12,20]
Total terpenes						0.28	0.01	0.08	0.49
	Other compounds
99	allyl isocyanate	15123	645		B	nd	nd	0.02 *	nd	-
100	2-ethylfuran	18554	701		A	0.16	nd	0.02	0.14 *	[3,21]
101	cyclohexyl isocyanate	18502	961		B	nd	0.01 *	nd	nd	-
102	1-isopropyl-3-methoxypyrazine	33166	1093		B	0.25	nd	0.09	nd	[15,25]
103	1,2,3,5-tetramethylbenzene	10695	1124		B	0.06 *	nd	nd	nd	-
104	veratrole	7043	1144		B	nd	nd	0.09 *	nd	-
105	octanoic acid	379	1157		B	0.10	nd	0.06	nd	[14,22]
106	2-sec-butyl-3-methoxypyrazine	520098	1172		B	0.15 *	nd	0.43	nd	[25]
107	phenethyl isocyanate	160602	1226	1807	B	nd	nd	0.41 *	0.70 *	-
108	quinoline	7047	1247		B	nd	nd	0.02 *	nd	-
109	caprolactam	7768	1251		B	0.05 *	nd	nd	nd	-
110	4-bromophenol	7808	1283		B	0.02 *	nd	nd	nd	-
111	6-methylquinoline	7059	1331		B	nd	nd	0.01 *	nd	-
112	methyleugenol	7127	1400		B	0.02 *	nd	nd	nd	-
113	benzyl tiglate	250096	1504		B	nd	nd	0.01 *	nd	-
Total other compounds						0.77	0.01	0.63	0.14

^a Linear retention index on a HP-5MS and Stabilwax columns. ^b A, mass spectrum and LRI agree with those of authentic compound; B, mass spectrum agrees with reference spectrum in the NIST/EPA/NIH mass spectra database and LRI agree with those in the literature, tentatively identified. ^ Based on library identification and spectra but two separate peaks were present; nd, not detected; * newly reported for species.