Biological pretreatment of lignocelluloses with white-rot fungi and its applications: A review

Abstract

Lignocellulosic carbohydrates, i.e. cellulose and hemicellulose, have abundant potential as feedstock for production of biofuels and chemicals. However, these carbohydrates are generally infiltrated by lignin. Breakdown of the lignin barrier will alter lignocelluloses structures and make the carbohydrates accessible for more efficient bioconversion. White-rot fungi produce ligninolytic enzymes (lignin peroxidase, manganese peroxidase, and laccase) and efficiently mineralise lignin into CO2 and H2O. Biological pretreatment of lignocelluloses using white-rot fungi has been used for decades for ruminant feed, enzymatic hydrolysis, and biopulping. Application of white-rot fungi capabilities can offer environmentally friendly processes for utilising lignocelluloses over physical or chemical pretreatment. This paper reviews white-rot fungi, ligninolytic enzymes, the effect of biological pretreatment on biomass characteristics, and factors affecting biological pretreatment. Application of biological pretreatment for enzymatic hydrolysis, biofuels (bioethanol, biogas and pyrolysis), biopulping, biobleaching, animal feed, and enzymes production are also discussed.

Solid-State Fermentation of Chestnut Shells and Effect of Explanatory Variables in Predictive Saccharification Models

“…Large differences within enzymatic activities detected in pretreated lignocellulosic substrates have been previously observed in several fungi, including all strains of this work [5,17,18,23]. As previously pointed out [36], this highlights the need to interpret the pattern of enzymatic activities detected as a function of interactions among fungal strains, substrates type and incubation periods.…”

“…More recently, VP was also isolated from fungal strains of genera Trametes [ 32 ], Phlebia [ 33 ], Ganoderma [ 34 ] and Irpex [ 35 ]. Taking into account that an efficient lignocellulosic pretreatment enhances enzyme accessibility and subsequent saccharification of structural polysaccharides [ 10 , 11 , 12 , 36 ], fungi should excrete an appropriated enzymatic balance between oxidoreductases and hydrolases.…”

“…Enzymatic pretreatments can be an alternative but present a major limitation of risk of reaction inhibition by phenolic compounds as well as the high capital cost involved for enzyme production and downstream processing [ 37 ]. Thus, solid-state fermentation with selected WRF is an attractive option for the pretreatment of various types of lignocellulosic residues [ 5 , 17 , 23 , 24 , 36 ] and can be important tools in the implementation of circular economy processes for the production of biofuels and other value-added chemicals, according to the concept of biorefinery and the principle of zero waste discharge [ 38 ].…”

Pretreatment of maize straw with Pleurotus ostreatus and Lentinus squarrosulus for bioethanol production using Saccharomyces cerevisiae

“…On the other hand, the nonselective white rot fungi biodegrade all components of lignocellulose equally (Hatakka and Hammel, 2010;Isroi et al, 2011). Among the white rot fungi that have been used for biodegradation of lignocellulose are Phanerochaete chrysoporium; Pleurotus ostreatus, Lentinus squarrosulus, Pycnoporus cinnarbariunus, Cyathus stercolerus, Ceriporiopsis subvermispora and Ceriporia lacerate, as reported by the recent studies conducted by Kumar and Sharma, (2017); Ganash et al, (2021).…”

Direct Ethanol Production from Xylan and Acorn Using the Starch-Fermenting Basidiomycete Fungus Phlebia acerina

“…Basidiomycete fungi are forest decomposers exhibiting lignocellulosic decomposing ability, while some, such as yeast, exhibit fermentability and can produce ethanol from lignocellulosic biomass [22][23][24][25][26]. Furthermore, several studies have focused on the fermentability of wild basidiomycete fungi and revealed that ethanol can be produced from unused resources, such as rice straw, wheat bran, kitchen waste, whey, and expired milk [27][28][29][30][31][32][33].…”