Induction of wheat straw delignification by Trametes species

Abstract

Wheat straw is the major crop residue in European countries which makes it the most promising material for bioconversion into biofuels. However, cellulose and hemicellulose are protected with lignin, so delignification is an inevitable phase in lignocellulose processing. The organisms predominantly responsible for its degradation are white-rot fungi and among them Trametes species represent promising degraders due to a well-developed ligninolytic enzyme system. Although numerous studies have confirmed that low molecular weight compounds can induce the production and activity of ligninolytic enzymes it is not clear how this reflects on the extent of delignification. The aim of the study was to assess the capacity of p-anisidine and veratryl alcohol to induce the production and activity of Mn-oxidizing peroxidases and laccases, and wheat straw delignification by six Trametes species. Significant inter- and intraspecific variations in activity and features of these enzymes were found, as well as differences in the potential of lignocellulose degradation in the presence or absence of inducers. Differences in the catalytic properties of synthesized enzyme isoforms strongly affected lignin degradation. Apart from enhanced lignin degradation, the addition of p-anisidine could significantly improve the selectivity of wheat straw ligninolysis, which was especially evident for T. hirsuta strains.

A novel and efficient fungal delignification strategy based on versatile peroxidase for lignocellulose bioconversion

“…In nature, lignin degradation is a multi-enzymatic process involving an array of accessory enzymes (such as producing hydrogen peroxides) in addition to the four major lignilolytic enzymes. Different fungal species have been reported to exhibit different degradation capacities towards lignin, and their efficiency mainly depends on the ligninolytic enzymes produced by the white-rot fungi [ 12 – 14 ], mainly including laccase (Lac, EC 1.10.3.2), manganese peroxidase (MnP, EC 1.11.1.13), lignin peroxidase (LiP, EC1.11.1.14), and versatile peroxidase (VP, EC 1.11.1.16) [ 12 ]. The production and activity of these enzymes as well as their ability to degrade lignin vary significantly in different species of white-rot fungi.…”

“…The production and activity of these enzymes as well as their ability to degrade lignin vary significantly in different species of white-rot fungi. Differences in the catalytic properties of these enzymes strongly affect lignin degradation [ 14 ]. Lacs possess relatively low redox potentials (0.48–0.78 V) that restrict their action to the oxidation of the nonphenolic lignin components [ 15 ].…”

Lignin-Degrading Abilities of Novel Autochthonous Fungal Isolates Trametes hirsuta F13 and Stereum gausapatum F28

“…( 41 ) is one of the few studies that used all four reagents for detection and measurement of laccase activity, and T. versicolor belongs to the group of fungi with highly active ligninolytic enzymes, which makes it suitable for comparison. Laccase activity of isolates F13 and F28 was measured using guaiacol, while the experiments with T. hirsuta in the literature have mainly used ABTS or syringaldazine ( 42 , 43 ). Guaiacol is the least sensitive reagent giving much lower laccase activity values than ABTS or syringaldazine.…”

Characterization of Kapok Pericarpium Microcrystalline Cellulose Produced of Enzymatic Hydrolysis Using Purified Cellulase From Termite (Macrotermes Gilvus)

“…Follow with the incubation process of kapok pericarpium and mycelium of Trametes versicolor in 30 d at 30 ⁰C and for 21 d at 40 ⁰C with the addition of nutrient solution. The mold of Trametes versicolor produces ligninolytic enzymes Laccase, Mn peroxidase (MnP), and Li peroxidase (LiP) [15,16].…”