17.3 Biological Pretreatment
273
Table 17.4
Fungi and bacteria participating in biological pretreatment of LCB.
Sl. No.
Microorganism
Category
Substrate
Incubation
(d)
Lignin
degradation
(%)
References
1.
Ceriporia lacerata
White-rot fungi
Red pine
56
13
[37]
2.
Ceriporiopsis
subvermispora
White-rot fungi
Corn stover
42
39.2
[37]
3.
Echinodontium
taxodii 2538
White-rot fungi
Bamboo
culms
28
24
[37]
4.
Irpex lacteus
White-rot fungi
Corn stalks
11.48
15
[35]
5.
Pleurotus ostreatus
White-rot fungi
Beech wood
120
56.5
[38]
6.
Phaenerochaete
chrysosporium
White-rot fungi
Cotton
stalks
30
40
[38]
7.
Phlebia sp. MG-60
White-rot fungi
Oak wood
56
40.6
[39]
8.
Stereum hirusutum
Brown-rot fungi
Red pine
56
13
[37]
9.
Trametes versicolor
spp.
White-rot fungi
Bamboo
culms
28
9–24
[37]
10.
Acinetobacter spp.
Actinobacteria
Poplar wood
30
47–57
[40]
11.
Pseudomonas spp.
Proteobacteria
Poplar wood
30
40–52
[38]
12.
Pseudomonas spp.
Proteobacteria
Kraft lignin
52
39
[38]
13.
Streptomyces
badius
Actinobacteria
Inulin lignin
35
3–4
[37]
14.
Streptomyces
cyaneus
Actinobacteria
Barley straw
21
29–52
[31]
15.
Streptomyces
virifosporus
Actinobacteria
Induline
lignin
35
3–4
[37]
16.
Thermomonospora
mesophila
Actinobacteria
Barley straw
21
36–48
[37]
17.
Xanthomonas spp.
Proteobacteria
Poplar wood
30
39–48
[39]
Phanerochaete chrysosporium is the most established prototype for studying the
lignin degrading properties of white-rot fungi. Shi et al. [38] evaluated the activity of
P. chrysosporium on cotton stalks to illustrate the efficacy of microbial pretreatment
to promote hydrolysis and fermentation facilitating bioethanol production under
two culture conditions: submerged cultivation and solid-state cultivation using
untreated stalk as control. It showed that about 28% of lignin was removed from the
substrate along with a significant amount of cellulose after 14 days of pretreatment.
This shifted the focus on fungal pretreatment using various other fungal strains such
as Ceriporiopsis subvermispora, Cyathus stercolerus, Pleurotus ostreaus, T. versicolor,
Phlebia subserialis, Sternum hirsutum, Gloeophyllum trabeum, and Echindodontium
taxodii [39] to promote selective lignin degradation. However, the carbon–carbon
bonds present within large lignin polymers pose a challenge to lignin degradation.