## 2 Results
### GC-MS Analysis
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**No.**} & \multirow{2}{*}{**Compounds**} & \multirow{2}{*}{**RT/min \({}^{*}\)**} & \multicolumn{4}{c}{**RI**} & \multicolumn{4}{c}{**Concentation (ug/L)**} & \multirow{2}{*}{**Identification \({}^{\circ}\)**} \\ \cline{3-3} \cline{5-10}  & & **Cal. \({}^{\bullet}\)** & & **Ref. \({}^{*}\)** & & **CK** & **T10** & **T20** & **T30** & **T40** & **T50** \\ \hline \multicolumn{10}{c}{**Ketones**} \\
1 & 2-Nonanone & 14.47 & 1310 & 1366 & 0.57 \(\pm\) 0.11 & 0.80 \(\pm\) 0.01 & 1.15 \(\pm\) 0.59 & 0.47 \(\pm\) 0.10 & 0.90 \(\pm\) 0.02 & 1.05 \(\pm\) 0.13 & MSSTD/RI \\
2 & 2-Undecanne & 19.73 & 1509 & 1599 & 0.41 \(\pm\) 0.06 & - \({}^{\circ}\) & 0.90 \(\pm\) 0.02 & 0.43 \(\pm\) 0.32 & 0.44 \(\pm\) 0.12 & 0.46 \(\pm\) 0.14 & MSSTD/RI \\
3 & Acetophenone & 20.87 & 1555 & 1627 & 0.06 \(\pm\) 0.01 & - & 0.09 \(\pm\) 0.01 & 0.07 \(\pm\) 0.03 & 0.03 \(\pm\) 0.00 & 0.05 \(\pm\) 0.02 & MSSTD/RI \\ Total & & & 1.05 \(\pm\) 0.12 \({}^{b}\) & 0.80 \(\pm\) 0.01 \({}^{b}\) & 21.15 \(\pm\) 0.82 \({}^{a}\) & 0.97 \(\pm\) 0.39 \({}^{b}\) & 1.38 \(\pm\) 0.13 \({}^{a}\) & 1.55 \(\pm\) 0.28 \({}^{b}\) & \\ \hline \multicolumn{10}{c}{**Acids**} \\
1 & Hexanoic acid & 25.74 & 1705 & 1850 & 1.03 \(\pm\) 0.33 & - & - & 1.33 \(\pm\) 0.01 & - & - & MSSTD/RI \\
2 & Octanoic acid & 30.06 & 1969 & 2038 & 7.55 \(\pm\) 2.53 & 4.06 \(\pm\) 2.66 & 7.13 \(\pm\) 2.52 & 14.75 \(\pm\) 7.97 & 9.19 \(\pm\) 3.14 & 9.97 \(\pm\) 2.16 & MSSTD/RI \\
3 & n-Decanoic acid & 34.07 & 2176 & 2246 & 6.60 \(\pm\) 2.06 & 3.50 \(\pm\) 1.98 & 6.26 \(\pm\) 3.04 & 9.94 \(\pm\) 4.92 & 7.07 \(\pm\) 2.12 & 6.90 \(\pm\) 3.69 & MSSTD/RI \\ Total & & & 15.18 \(\pm\) 3.50 \({}^{b}\) & 7.56 \(\pm\) 4.64 \({}^{b}\) & 13.39 \(\pm\) 5.35 \({}^{b}\) & 26.01 \(\pm\) 12.76 \({}^{b}\) & 16.26 \(\pm\) 5.16 \({}^{b}\) & 16.87 \(\pm\) 5.78 \({}^{b}\) & \\ \hline \multicolumn{10}{c}{**Aldehydes**} \\
1 & Octanal & 11.78 & 1214 & 1292 & - & - & - & 0.18 \(\pm\) 0.14 & - & 0.23 \(\pm\) 0.09 & MSSTD/RI \\
2 & Nonanal & 14.55 & 1313 & 1390 & 0.56 \(\pm\) 0.18 \(\pm\) 0.12 & 1.41 \(\pm\) 0.63 & 1.42 \(\pm\) 0.08 & 0.59 \(\pm\) 0.15 & 1.46 \(\pm\) 0.33 & MSSTD/RI \\
3 & Decanal & 17.23 & 1412 & 1472 & - & 1.46 \(\pm\) 0.29 & 1.86 \(\pm\) 0.63 & 0.98 \(\pm\) 0.37 & 2.33 \(\pm\) 1.55 & 4.39 \(\pm\) 2.13 & MSSTD/RI \\ Total & & & 0.56 \(\pm\) 0.18 \({}^{b}\) & 2.27 \(\pm\) 0.03 \({}^{b}\) & 3.27 \(\pm\) 1.24 \({}^{b}\) & 2.58 \(\pm\) 1.17 \({}^{b}\) & 2.91 \(\pm\) 1.70 \({}^{b}\) & 6.09 \(\pm\) 2.54 \({}^{b}\) & \\ \hline \multicolumn{10}{c}{**Alcohols**} \\
1 & 2-Ethyl-1-hexanol & 17.16 & 1410 & 1484 & 3.93 \(\pm\) 0.20 & 3.63 \(\pm\) 0.34 & 5.92 \(\pm\) 3.19 & 2.46 \(\pm\) 0.14 & 2.17 \(\pm\) 0.69 & MSSTD/RI \\
2 & 1-Octanol & 18.83 & 1474 & 1558 & 0.27 \(\pm\) 0.04 & 0.19 \(\pm\) 0.03 & 0.40 \(\pm\) 0.10 & 0.51 \(\pm\) 0.33 & 0.20 \(\pm\) 0.01 & 0.47 \(\pm\) 0.18 & MSSTD/RI \\ Total & & & & 4.20 \(\pm\) 0.17 & 3.82 \(\pm\) 0.37 & 6.32 \(\pm\) 3.14 & 4.73 \(\pm\) 3.51 & 2.65 \(\pm\) 0.15 & 2.64 \(\pm\) 0.87 & \\ \hline \multicolumn{10}{c}{**AlAlances**} \\
1 & Tetradecane & 14.81 & 1323 & 1400 & - & 0.34 \(\pm\) 0.17 & 0.93 \(\pm\) 0.13 & 0.15 \(\pm\) 0.01 & 0.19 \(\pm\) 0.05 & 0.14 \(\pm\) 0.05 & MSSTD/RI \\ Total & & & & - & 0.34 \(\pm\) 0.17 \({}^{b}\) & 0.93 \(\pm\) 0.13 \({}^{a}\) & 0.15 \(\pm\) 0.01 \({}^{b}\) & 0.19 \(\pm\) 0.05 \({}^{b}\) & 0.14 \(\pm\) 0.05 \({}^{b}\) & MSSTD/RI \\ \hline \multicolumn{10}{c}{**Sulfor compounds**} \\
1 & Dimethyl sulfone & 26.28 & 1789 & 1895 & 0.10 \(\pm\) 0.00 & - & - & 0.15 \(\pm\) 0.10 & - & - & MSSTD \\ Total & & & & 0.10 \(\pm\) 0.00 & - & - & 0.15 \(\pm\) 0.10 & - & - & MSSTD \\ \hline \multicolumn{10}{c}{\({}^{a}\).b. Significant (\(p<0.05\)) difference between samples. \({}^{a}\) Retention time on DB-WAX column. \({}^{b}\) Retention indices calculated on DB-WAX column against n-alkanes. \({}^{b}\) Retention indices reported by [[http://webbook.nist.gov/chemistry/cas-exclm1](http://webbook.nist.gov/chemistry/cas-exclm1)]([http://webbook.nist.gov/chemistry/cas-exclm1](http://webbook.nist.gov/chemistry/cas-exclm1)). \({}^{a}\) not detected. \({}^{b}\) Volatiles were identified according to abbreviations: MS, comparing mass spectrum with those in NIST library. STD, comparing the retention time of compounds in samples to authentic standards. RI, comparing linear retention indices (RI) on DB-Wax column with those in the literature. \\ \hline \hline \end{tabular}
\end{table}