Table 2 Phenolic compounds identified by GC-MS in initial SBL and in samples post-treated with P. ostreatus and P. pastoris.

From: Detoxification of pulping black liquor with Pleurotus ostreatus or recombinant Pichia pastoris followed by CuO/TiO2/visible photocatalysis

RT (min)

Detection of compounds

Compounds

a

b

c

d

e

7.83

+

+

2-chlorophenol

8.90

+

+

2-methylphenol

9.29

+

+

4-methylphenol

10.28

2-nitrophenol

10.47

+

2,4-dimethylphenol

11.36

+

+

2,4-dichlorophenol

13.26

2,3,5-trichlorophenol

13.59

2,4,5-trichlorophenol

14.68

+

+

2-methoxyphenol (guaiacol)

15.96

+

2,6-dimethoxyphenol (siryngol)

16.38

+

2-methoxy-4-ethyl-phenol (4-ethyl guaiacol)

19.04

3-aryl-6-methoxyphenol (m-eugenol)

  1. The presence of chlorophenol could be related to the alkaline extraction process to obtain SBL. Under this condition, free aromatic rings were unstable and could be chlorinated by the presence of small quantities of Cl2 in the water. Both fungi were able to biotransform chlorinated and non-chlorinated phenolic compounds, although the modifications by the native fungus and recombinant yeast were distinct.
  2. RT: Retention time (min); a: Initial phenol in SBL; b: SBL treated with P. ostreatus for 192 h; c: SBL treated with P. pastoris for 192 h; d: SBL treated with P. ostreatus and Cu/TiO2 for 10 h; e: SBL treated with P. pastoris and CuTiO2 for 10 h; +present; absent.