## 3 Results and Discussion
### Volatile Compounds
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
**Compound** & \multicolumn{3}{c}{**LRI \({}^{*}\)**} & \multicolumn{3}{c}{**Peak Areas (\% of total)**} & \multicolumn{3}{c}{**References**} \\ \cline{3-10}
**Number** & **Compound** & **PubChem ID** & **HP-SMS** & **Stabilivas** & **ID \({}^{b}\)** & **Salad Rocket** & **Wassibi** & **Hersersandish** & **Watterers** & **References** \\ \hline \hline \multicolumn{10}{c}{**Salabr-sentative compounds**} \\
1 & carton chusulfide & 6388 & -6000 & 728 & B & 0.43\({}^{*}\) & 0.04\({}^{*}\) & 0.02 & 0.11\({}^{*}\) & [21] \\
2 & methyl thresmare & 11168 & 711 & 1296 & B & 0.13 & nd & nd & 0.48 & [21] \\
3 & isopropyl ITC & 7583 & 835 & 1176 & B & nd & 4.07 & 0.03 & nd & [22] \\
4 & allyl thresmare & 69616 & 800 & 1358 & B & nd & 0.48\({}^{*}\) & 0.73 & nd & [22] \\
5 & allyl ITC & 5971 & 881 & 1371 & B & nd & 8.61 & 7.35 & nd & [2,34,18,24] \\
6 & allyl ITC & 5971 & 890 & 1392 & B & nd & 52.11 & 39.34 & nd & [2,34,18,24] \\
7 & cyclopropan IPC & 72463 & 899 & 1223 & B & nd & 0.07\({}^{*}\) & 0.05\({}^{*}\) & nd & - \\
8 & cyclopropan IPC & 113983 & 922 & 1068 & B & nd & nd & nd & 0.51\({}^{*}\) \\
9 & sex-butyl ITC & 78151 & 933 & 1265 & B & 0.46\({}^{*}\) & 4.95 & 1.84 & nd & [2,32] \\
10 & incubator ITC & 68000 & 955 & 1316 & B & nd & 1.80 & 0.45 & nd & [2,31] \\
11 & 3-busbusITY ITC & 76922 & 982 & 1458 & B & 0.19 & 4.24 & 1.52 & nd & [2,37,22] \\
12 & butyl ITC & 11633 & 998 & 1597 & B & 0.57 & 0.12 & 0.32 & nd & [2,33] \\
13 & isomomil ITC & 70966 & 1059 & 1431 & B & 0.10 & 0.41\({}^{*}\) & 0.55 & 0.07 & [13,82] \\
14 & 4-opennet ITC & 87436 & 1066 & 1543 & B & nd & 12.42 & 2.26 & nd & [22] \\
15 & permit ITC & 69415 & 1098 & 1488 & B & 0.56\({}^{*}\) & 0.12\({}^{*}\) & 0.20 & nd & [21] \\
16 & methyl/guamate & 591482 & 1162 & 1522 & B & 4.96 & 0.01\({}^{*}\) & 0.04 & 0.18 & [13,82] \\
17 & cyclopropan IPC & 14289 & 1177 & 1650 & B & nd & 0.01\({}^{*}\) & nd & nd & - \\
18 & cyclidentified ITC & 11593 & 1159 & & d & 8.57 & nd & nd & [21] \\
19 & heuristic & 62351 & 1315 & 1991 & B & 0.58 & 0.29 & 1.02 & nd & [3,7,22] \\
20 & sativu & 8570488 & 1353 & -2020 & B & 0.55 & nd & nd & nd & [21] \\
21 & cell/ITC & 73616 & 1322 & 1760 & B & nd & nd & nd & 0.16\({}^{*}\) \\
22 & benzyl ITC & 2364 & 1372 & -2000 & B & nd & 0.03 & 1.4 & nd & [2,22] \\
23 & exitan & 73640 & 1449 & -2020 & B & 7.16 & 0.01 & 0.22 & nd & [2,32,21] \\
24 & phenhenyl ITC & 16741 & 1677 & -2020 & B & nd & 0.68 & 32.47 & 30.72 & [7,31,82,24] \\ \hline \multicolumn{10}{c}{**Total sulphur-containing compounds**} \\ \hline \hline \multicolumn{10}{c}{**Methods**} \\
25 & 1-penten-3-ol & 12020 & 678 & 1159 & A & 0.78 & nd & 0.10\({}^{*}\) & 8.06 & [7,7,18] \\
26 & penten-1-ol & 6276 & 763 & 1251 & A & 0.13\({}^{*}\) & 0.02\({}^{*}\) & 0.02\({}^{*}\) & 0.25\({}^{*}\) & - \\
27 & (2)-2-penten-1-ol & 506499 & 763 & 1322 & A & 0.17\({}^{*}\) & nd & nd & 0.31\({}^{*}\) & - \\
28 & (2)-2-penten-1-ol & 15306 & 767 & 1322 & A & 0.76 & nd & 0.06 & 4.78 & [2,2] \\
29 & 1-propov-2-pippan & 15286 & 840 & B & nd & nd & nd & 0.24\({}^{*}\) & - \\
30 & (2)-3-berent-1-ol & 5284503 & 850 & 1365 & A & nd & nd & 0.20 & [3,19,22] \\
31 & (2)-3-berent-1-ol & 528167 & 856 & 1387 & A & 40.88 & nd & 1.88 & 35.99 & [13,82] \\
32 & 2-berent-ol & 5318042 & 863 & 1465 & A & 1.25 & nd & nd & 0.35 & [2,31,82,24] \\
33 & hexan-1-ol & 51803 & 866 & 1355 & A & 4.82\({}^{*}\) & nd & 0.22 & 2.61 & [7,18] \\
34 & 1-octn-3-ol & 18827 & 977 & A & 0.18 & 0.01\({}^{*}\) & 0.02\({}^{*}\) & 0.06\({}^{*}\) & [14] \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Volatile compounds identified in the headspace of four Brassicles species analysed by HS-SPME CC-MS.