## 2 Results and Discussion
### Headspace, Volatile, and Semi-Volatile Organic Compounds
& \(\delta\)-3-Carene \({}^{\text{S}}\) & 1013 & 1013 & - & 0.10 & - & 0.30 & & & & \\  & & & & \(\pm\) 0.01\({}^{\text{a}}\) & - & \(\pm\) 0.01\({}^{\text{a}}\) & - & - & - \\ \hline
18. & \(p\)-Cymene \({}^{\text{S}}\) & 1031 & 1031 & 0.51 & - & - & 0.10 & & & & \\  & & & & \(\pm\) 0.02\({}^{\text{a}}\) & - & - & \(\pm\) 0.01\({}^{\text{a}}\) & - & - & - \\ \hline
19. & \(2\)-Ethyl-hexan-1-ol \({}^{\text{S}}\) & 1032 & 1031 & - & 0.40 & - & 0.72 & & & & \\  & & & & \(\pm\) 0.01\({}^{\text{a}}\) & - & \(\pm\) 0.01\({}^{\text{a}}\) & - & - & - & - \\ \hline
20. & Limonene \({}^{\text{S}}\) & 1035 & 1035 & \(\frac{2.20}{\pm 0.09\({}^{\text{a}})}\) & - & - & - & - & - & - \\ \hline
21. & Benzyl alcohol \({}^{\text{S}}\) & 1037 & 1037 & \(\frac{9.31}{\pm 0.30\({}^{\text{a}})}\) & \(\pm\) 0.09\({}^{\text{b}}\) & \(\pm\) 0.01\({}^{\text{c}}\) & \(\pm\) 0.03\({}^{\text{b}}\) & \(\pm\) 1.04\({}^{\text{d}}\) & \(\pm\) 0.001\({}^{\text{c}}\) & - \\ \hline
22. & (E)-Oct-2-2 penal \({}^{\text{S}}\) & 1061 & 1062 & - & 0.80 & - & 0.11 & & & \\  & & & & \(\pm\) 0.01\({}^{\text{a}}\) & - & \(\pm\) 0.01\({}^{\text{a}}\) & - & - & - & - \\ \hline
23. & Octan-1-ol \({}^{\text{S}}\) & 1074 & 1074 & 0.62 & 0.71 & 0.20 & 0.3  
The major headspace compound of fresh _C. bursa_ (HS-F) was 2-thiapropane (dimethyl sulfide, DMS) ranging from 36.22% to 56.51%, being more abundant when applying HS-SPME with DVB/CAR/PDMS fiber. It has long been recognized that algae play a highly significant role in the global biogeochemical cycles of sulfur. The key chemical compounds driving these cycles are often low molecular weight and/or volatile compounds. In the case of sulfur, a dominant compound is dimethyl sulfide (DMS), algal osmolyte, which derives from dimethylsulfoniopropionate (DMSP) that has been synthetized and accumulated in a wide range of taxa which occur in diverse ecosystems [29]. DMSP and its breakdown products (e.g., DMS) readily scavenge hydroxyl radicals and other reactive  
\begin{table}
\begin{tabular}{l c c c c c c c c c} \hline \hline \multirow{2}{*}{**No**} & \multirow{2}{*}{**Compound**} & \multirow{2}{*}{**RI**} & \multirow{2}{*}{**RI\({}_{\text{L}}\)**} & \multicolumn{6}{c}{**Area Percentages (\%)**} \\ \cline{6-11}  & & & & **I** & **II** & **III** & **IV** & **V** & **VI** & **VII** \\  & & & & \(\pm\) **SD** & \(\pm\) **SD** & \(\pm\) **SD** & \(\pm\) **SD** & \(\pm\) **SD** & \(\pm\) **SD** \\ \hline
46. & Heptadecane [5] & \multirow{2}{*}{\(1700\)} & \multirow{2}{*}{\(1700\)} & \(4.82\) & 41.50 & 32.51 & 52.62 & 23.44 & 9.41 & 7.20 \\  & & & \(\pm\) 0.16  & \(\pm\) \(\pm\) 1.85  & \(\pm\) 1.01  & \(\pm\) 0.08 [FOOTNOTE:]Footnote : footnotemark: [ENDFOOTNOTE] \\ \hline
47. & Loligide & \(1763\) & - & - & - & - & - & - & \(\pm\) 0.08 [FOOTNOTE:]Footnote : footnotemark: [ENDFOOTNOTE] \\ \hline
48. & Octadecane [8] & \multirow{2}{*}{\(1800\)} & \multirow{2}{*}{\(1800\)} & \multirow{2}{*}{\(1838\)} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} \\  & & & & \(\pm\) 0.01  & & & & \\ \hline
49. & Neophyta-diene [8] & \multirow{2}{*}{\(1840\)} & \multirow{2}{*}{\(1838\)} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{\(\pm\) 0.11 [FOOTNOTE:]Footnote : footnotemark: [ENDFOOTNOTE] } \\ \hline
50. & Hexhydro-farmesyl acetone (Phytone)  & \(\pm\) 0.11 [FOOTNOTE:]Footnote : footnotemark: [ENDFOOTNOTE] \\ \hline
51. & Disobutyl phthalate [5] & \multirow{2}{*}{\(1867\)} & \multirow{2}{*}{\(1868\)} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{0.40} & \multirow{2}{*}{2.22} & \multirow{2}{*}{0.82} & \multirow{2}{*}{-} \\  & & & & & & \(\pm\) 0.01  & \(\pm\) 0.02  \\ \hline
52. & Nonadec-1-ene  & - & \(\pm\) 0.02  & \(\pm\) 0.02 [FOOTNOTE:]Footnote : footnotemark: [ENDFOOTNOTE] \\ \hline
53. & Hexadecan-1-ol  & \(\pm\) 0.21 [FOOTNOTE:]Footnote : footnotemark: [ENDFOOTNOTE] \\ \hline
54.