Table 4 Biological pretreatment using various microalgal strains and its effect after pretreatment on biomasses

Fungal pretreatment

 Pleurotus florida

Cultured on potato dextrose agar media

Cellulase

19.9% delignification, 83.2% cellulose recovery

[116]

 Pleurotus eryngii

Cultured on potato dextrose plate, 28 ℃ for 7 days

Xylanase, laccase

42.4% lignin degradation, 85.6% cellulose recovery

[118]

 (Phanerochaete chrysosporium

Potato dextrose agar media, 28 ℃, 84 h

Arabinose, xylanase

41.23% cellulose, 29.34% hemicellulose, 3.66% lignin

[121]

 Trichoderma reesei & Pleurotus ostreatus

Cultured on potato dextrose agar media

33.4% lignin removal

[125]

 Irpex lacteus

Obtained from mycelium culture

Cellulase

59.2% glucan digestibility, 45.8% lignin degradation

[126]

 Trichoderma harzianum

Cultured on potato dextrose agar media

Cellulase, β glucosidase, xylanase

Increase ethanol production by up to 38.2%

[127]

 Fusarium oxysporum

(Zinc oxide nanoparticles)

Potato dextrose agar media, 121 ℃, 20 min

Cellulase, xylanase, β-glucosidase

48.8% cellulose, 16.7% lignin

[129]

Bacterial pretreatment

 Galactomyces sp.

Inoculated in growth media containing 1 g (NH₄)₂SO₄, 0.05 g K₂HPO₄, 0.05 g MgSO₄.7H₂O, 0.05 g CaCl₂, at 180 rpm for 72 h

Cellulase, β-glucosidase, xylanase

50.6% cellulose, 7.4% hemicellulose, 12.6% lignin

[133]

 Pandoraea sp.

Bamboo

Manganese peroxidase and laccase

42.6% cellulose, 41.6% hemicellulose, 12.9% lignin

[134]

 Streptomyces griseorubens

The microbiological culture collection centre

Cellulase and xylanase

After 20 days, 65.63% cellulose, 11.89% hemicellulose, 2.81% lignin

[135]

 Ochrobactrum oryzae

Termite gut

Xylanase

52% cellulose, 24.05% hemicellulose, 10.04% lignin

[136]