Lignin Degradation by Fungal Pretreatment: A Review

Abstract

Lignin is regarded as the most plentiful aromatic polymer contains both non-phenolic and phenolic structures. It makes the integral part of secondary wall and plays a significant role in water conduction in vascular plants. Many fungi, bacteria and insects have ability to decrease this lignin by producing enzymes. Among these fungi are the major player in degradation of lignin. These fungi produce enzymes such as lignin peroxidases and laccases. The well-known fungi which degrades lignin are white, brown, soft-rot fungi, and deuteromycetes. Currently these fungi are utilized to reduce lignin to produce ecofriendly bioenergy. The primary aim of this paper is to describe the lignin degradation by biological pre-treatment using fungi (white-, brown-soft-rot fungi and molds), as well as biochemical application. Besides, Molecular methods and enzymes regulation engaged in fungal pre-treatment and some of the factors affecting pretreatment will also be briefly discussed.

Toward sustainable processes of pretreatment technologies of lignocellulosic biomass for enzymatic production of biofuels and chemicals: A review

“…"Biomass pretreatment review," BioResources 15(4), 10063-10088. 10075 various types of microbes that enhance the digestibility of organic matter (Maurya et al 2015;Madadi and Abbas 2017). Biological pretreatments have low energy requirements and are carried out under mild environmental conditions.…”

The Nutritional Value Enhancement of Oil Palm Empty Fruit Bunches as Animal Feed Using the Fungus Coprinus Comatus, with Different Numbers of Inoculums and Incubation Times

“…However, the optimum amount of inoculum at pretreatment T Versicolor was 15%, while P ostreatus was 10%. In addition, the whiterot fungi are the most efficient group due to their ability to degrade lignin compared to the brown and soft rot, which are limited to hemicellulose and cellulose degradation [22]. An increase in cellulose levels suggests that the Coprinus comatus uses only lignin as an energy source in fermentation.…”

Fungal Pretreatment of Lignocellulosic Materials

“…The time required for the colonization of the substrate is affected by the type and amount of inoculums [31]. Higher concentration of inoculum will lead to shorter time of colonization of the substrate [49].…”

“…There are several purposes of aeration such as to supply oxygen into the media, for the removal of CO 2 , heat dissipation, distribution of water vapor to regulate humidity, and circulation of volatile compounds produced during metabolism. Thus, this factor should be optimized to improve rate of delignification [49].…”