Lignin degradative pathway

A scheme for the formation of guaiacols from ferulic acid has also been proposed by Manley et al. (1974). The biosynthesis of various phenolic acids from p-coumaric acid (H.84) was studied by Friedrich (1976). Formation pathways for simple phenols in food flavors have been reviewed (Maga, 1978a). The two primary pathways could be the decarboxylation of phenolic carboxylic acids and the thermal degradation of lignin. Secondary pathways include bacterial, fungal, yeast enzymic and glycosidic reactions. 

Lignin A family of compounds of related biopol3miers based on phenylpropyl units that are linked by strong C—C bonds resistant to many degradation pathways. 

It was determined that these ceriporic acids suppressed iron redox reactions to attenuate OH production by the Fenton reaction in the presence of iron reductants such as hydroquinone and cysteine. It was proposed that the suppression of the cellulolytic active oxygen species, OH, by this metabolite contributes to the selective lignin-degradation with a minimum loss of cellulose. The absolute configuration of ceriporic acids, their stereoselective biosynthetic pathway and the diversity of their metabolites have been largely discussed. 

It is difficult to describe a detailed degradation pathway for lignosulfonates for several reasons. Firstly, the chemical structure of lignosulfonates is complex, which complicates a mechanistic understanding of the degradation process. Secondly, lignin and... 

Pyrolysis of biomass is defined as the chemical degradation of the biopolymers (cellulose, lignin and hemicellulose) constituting the wood fuel which initially requires heat. As can be seen in Figure 51, all reaction pathways making up the pyrolysis are not endothermic, which implies that some of the pyrolysis reactions generate heat. However, overall the pyrolysis process is endothermic. 

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