## 3 Results
### Thermal Desorption-Gas Chromatography-Mass Spectrometry of the Melanin from Ochroconis lascauxensis
The chromatograms of the melanins pyrolyzed at 500 \({}^{\circ}\)C (Figure 1A-C); Table 1 evidenced only a few pyrolysis products from polysaccharides, however at 300 \({}^{\circ}\)C (Figure 2A) numerous markers of carbohydrate pyrolysis were clearly observed in the untreated melanin, as denoted the peaks of anhydrodeoxyspentenulose (15), levoglucosenone (23), dianhydromannopyranose (31), dianhydroglucopyranoside (32), anhydrogalactosan (33), anhydromannosan (34), galactosan (50), mannosan (53), and levoglucosan (57), among others. This change in the pyrolyzate composition was due to the use of a lower temperature, suitable for the pyrolysis of polysaccharides, because 500 \({}^{\circ}\)C conducted to an extensive \begin{table}
\begin{tabular}{c c c c} \hline
**Peak** & **Compound** & **Peak** & **Compound** \\ \hline
18 & \(n\)-Butylthiophene & 75 & Phenylheptanoic acid \\
19 & Acetophenone & 76 & Tetadecanoic acid \\
20 & Heptanoic acid & 77 & \(n\)-Undecylbenzene \\
21 & Methylphenol & 78 & 2-Hexadecanone \\
22 & Nonanal & 79 & Phenanthrene \\
23 & Levoglucosenone & 80 & Pentadecanoic acid \\
24 & Benzeneacetonitrile & 81 & Dibutylphthalate \\
25 & \(n\)-Pentylbenzene & 82 & \(n\)-Dodecylbenzene \\
26 & \(n\)-Pentylthiophene & 83 & Hexadecanonitrile \\
27 & Octanoic acid & 84 & Tetadecylfuran \\
28 & 2-Decanone & 85 & Hexadecan acid methyl ester \\
29 & Naphthalene & 86 & Hexadecenoic acid \\
30 & Benzoic acid & 87 & Hexadecanoic acid \\
31 & Dianhydromannopyranose & 88 & Hexahydro-(methylpropyl)-pyrrolo- \\
32 & Dianhydrodinocypyranose & 89 & Diketopyrazine (from Pro-Val dipeptide) \\
33 & Anhydrogalactosa & 90 & Diethoxy-tetrahydro-dropyrrolozyme \\
34 & Anhydromannosan & 91 & Heptadecanoic acid \\
35 & \(n\)-Hexylbenzene & 92 & Octadecenitrile \\
36 & \(n\)-Hexylthiophene & 93 & Octadecedienoic acid methyl ester \\
37 & Phenylbutanone & 94 & Octadecenoic acid methyl ester \\
38 & Nonanoic acid & 95 & Octadecanoic acid methyl ester \\
39 & \(n\)-Tridecene & 96 & Octadecanitrile \\
40 & 2-Undecanone & 97 & Hydroxyadecactic acid \(\gamma\)-lactone \\
41 & Indole & 98 & Octadecadienoic acid \\
42 & Methylnaphthalene & 99 & Octadecenoic acid \\
43 & Pentyfluranone & 100 & Octadecanoic acid \\
44 & Phenylpentanone & 101 & Octadecanoic acid ethyl ester \\
45 & \(n\)-Heptylbenzene & 102 & \(n\)-Pentadecylbenzene \\
46 & Decanoic acid & 103 & Hexadecanamide \\
47 & \(n\)-Tetadecene & 104 & \(n\)-Tricosen \\
48 & Biphenyl & 105 & \(n\)-Hexadecylbenzene \\
49 & \(n\)-Tetadecane & 106 & Hydroxyoctadecanoic acid \(\gamma\)-lactone \\
50 & Galactosan & 107 & Octadecenamide \\
51 & Phenylhexanone & 108 & Octadecanzide \\
52 & Octylbenzene & 109 & Bis-(2-ethylhexyl)-phthalate \\
53 & Mannosan & 110 & Squalene \\
54 & \(n\)-Pentadecene & 111 & Hexadecanoic acid dodecyl ester \\
55 & \(n\)-Pentadecane & 112 & Antihaergosta-1,5,7,9,22-pentaene \\
56 & Dihydroindolone & 113 & Antihaergostan-5,7,9,16,22-pentene \\
57 & Levoglucosan & & \\ \hline \end{tabular}
\end{table} 
Table 2: \(Cont.\)thermal degradation of the polysaccharide markers, as well as contributed to the excessive production of all types of pyrolysis products, and the difficulty to resolve such a high amount of compounds in the column. Nitrogen derivatives were represented by a few compounds such as indole (peak 41) and octadecanitrile (peak 95) and minor amounts of diketodipyrrole, pyrazines, and pyrrolopyrazines (peaks 62, 76-78, 81), denoting that the temperature applied was not suitable for a complete pyrolysis of proteins. In addition, peaks of hexadecanamide, octadecanamide, and octadecanamide (101, 104, 105) reached relatively low intensity. Minor products were represented by the series of \(n\)-alkanes (C\({}_{9}\)-C\({}_{19}\)), and \(n\)-alkenes that reached very low intensity and were mainly evidenced using the ion mass chromatograms.