Table 2 Relative molar abundances of lignin markers from Py-GC/MS of eucalypt wood treated with laccase-mediator, laccase alone and control

Guaiacol (G)

4.4

4.8

6.4

4-methylguaiacol (G-CH3)

2.6

2.0

1.2

4-ethylguaiacol (G-CH2-CH3)

1.0

1.2

1.2

4-vinylguaiacol (G-CH = CH2)

4.0

3.5

2.9

Eugenol (G-CH2-CH = CH2)

0.9

0.8

0.5

Syringol (S)

19.2

21.7

32.0

cis-isoeugenol (G-CH = CH-CH3)

0.7

0.5

0.3

trans-isoeugenol (G-CH = CH-CH3)

4.0

3.6

2.0

4-methylsyringol (S-CH3)

7.5

7.2

5.0

Vanillin (G-CHO)

1.3

1.0

0.7

4-ethylsyringol (S-CH2-CH3)

3.5

3.8

5.3

Acetovanillone (G-CO-CH3)

0.7

0.9

1.1

4-vinylsyringol (S-CH = CH2)

13.3

12.4

12.3

Guaiacylacetone (G-CH2-CO-CH3)

0.5

0.5

0.5

4-allylsyringol (S-CH2-CH = CH2) + 4-propylsyringol (S-CH2-CH2-CH3)

4.3

4.1

3.6

cis-propenylsyringol (S-CH = CH-CH3)

2.6

2.3

1.8

trans-propenylsyringol (S-CH = CH-CH3)

14.4

12.8

10.2

Syringaldehyde (S-CHO)

5.8

4.5

2.5

Homosyringaldehyde (S-CH2-CHO)

0.0

1.1

0.9

Acetosyringone (S-CO-CH3)

3.6

5.0

4.9

Syringylacetone (S-CH2-CO-CH3)

2.2

2.2

2.3

Propiosyringone (S-CO-CH2-CH3)

0.7

0.8

0.6

Dihydrosinapyl alcohol (S-CH2-CH2-CH2OH)

0.7

0.8

0.5

trans-sinapyl alcohol (S-CH = CH-CH2OH)

0.8

0.2

0.3

trans-sinapaldehyde (S-CH = CH-CHO)

1.0

2.3

1.0

C₆-C_0-2/C₆-C₃ ratio

2.0

2.2

3.2

Syringyl-to-guaiacyl ratio

4.0

4.3

4.9