Impact of Lignin Structure and Cell Wall Reticulation on Maize Cell Wall Degradability

Abstract

In this study, eight maize recombinant inbred lines were selected to assess both the impact of lignin structure and the impact of cell wall reticulation by p-hydroxycinnamic acids on cell wall degradability independently of the main "lignin content" factor. These recombinant lines and their parents were analyzed for in vitro degradability, cell wall residue content, esterified and etherified p-hydroxycinnamic acid content, and lignin content and structure. Lignin structure and esterified p-coumaric acid content showed significantly high correlation with in vitro degradability (r=-0.82 and r=-0.72, respectively). A multiple regression analysis showed that more than 80% of cell wall degradability variations within these 10 lines (eight recombinant inbred lines and their two parents) were explained by a regression model including two main explanatory factors: lignin content and estimated proportion of syringyl lignin units esterified by p-coumaric acid. This study revealed new biochemical parameters of interest to improve cell wall degradability and promote lignocellulose valorization.

Formulation of enzyme blends to maximize the hydrolysis of alkaline peroxide pretreated alfalfa hay and barley straw by rumen enzymes and commercial cellulases

“…It has been reported that xylo-oligomers are strong inhibitors of cellulase and inclusion of β-xylosidase ( Trichoderma ) reduces the inhibitory impact of these end products on cellulose hydrolysis [16]. Furthermore, xylanases ( Thermoascus aurantiacus ) alone have been shown to enhance the bioconversion of both cellulose and hemicellulose [19]. …”

Bioconversion of agricultural lignocellulosic residues into branched-chain fatty acids usingStreptomyces lividans

“…Indeed, aryl ether bonds are known as labile bonds, less resistant to chemical and biological attacks than other lignin inter-unit bonds. However, they may limit bioconversion of polysaccharides because of the barrier effect, as previously observed for maize (Zhang et al, 2011).…”

“…This structural parameter, in addition to giving an indication of the global lignin content, is likely to influence the cell wall properties and the bioconversion of lignocellulose. Indeed, Zhang et al (2011) discovered a negative correlation between thioacidolysis yield and the enzymatic degradability of maize stems using a commercial cellulolytic cocktail.…”

Isolation of structurally distinct lignin–carbohydrate fractions from maize stem by sequential alkaline extractions and endoglucanase treatment

“…Ester-and ether-linked p-coumaric acid (CA) and ferulic acid (FA) were determined by mild and severe alkaline hydrolysis, respectively, as described by Zhang et al (2011).…”