Digestibility of silages in relation to their hydroxycinnamic acid content and lignin composition

Abstract

BACKGROUND: The effectiveness of the analysis of cell wall‐bound hydroxycinnamic acids and the composition of lignin to evaluate the in vivo digestibility of a silage collection with unknown botanical composition was evaluated. RESULTS: Syringyl units content and total etherified phenols showed the highest correlation coefficients with in vivo dry matter digestibility (IVDMD) (r = − 0.792 and r = − 0.703, respectively), while guaiacyl units and total phenols showed the highest correlation coefficients with in vivo organic matter digestibility (IVOMD) (r = − 0.871 and r = − 0.817, respectively). Using the above‐mentioned chemical parameters, 10 equations were also developed to predict in vivo digestibility. The prediction of IVDMD produced a high adjusted R2 value (0.710) using syringyl, total lignin, etherified total phenols, esterified ferulic acid and total phenol content as predictors. The prediction of IVOMD produced a higher adjusted R2 value (0.821) using guaiacyl, total phenols, total ferulic acid and etherified p‐coumaric acid content as predictors. CONCLUSION: Cell wall digestibility depends on a multiplicity of factors and it is not possible to attribute a causal effect on in vivo digestibility to any single factor. However, syringyl and guaiacyl content and etherified phenols emerge as good predictors of digestibility. Copyright © 2010 Society of Chemical Industry

Algae as nutritional and functional food sources: revisiting our understanding

“…Although the ingestion of green macroalgae by humans is rather widespread, the potential health benefits of food supplements of native ulvans or their chemically modified derivatives, let alone the direct consumption of the whole algae, are not well understood (Taboada et al 2010; Wijesekara et al 2011). Fermentation of Ulva and ulvan by human colonic bacteria was slight (16.6 and 8.9 % of organic matter, respectively) (Durand et al 1997), indicating that they would be poor sources of SCFA production in the colon (Bobin-Dubigeon et al 1997).…”

Current Understanding of the Correlation of Lignin Structure with Biomass Recalcitrance

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“…Rather than cross-linking inter-components in cell wall, p CA are usually esters pendantly linked on lignin (γ-position of S unit), but they are also found to acylate to polysaccharides (Petrik et al, 2014). The accumulation of p CA indicating lignin deposition level in plants is likely one reason for recalcitrance (Taboada et al, 2010). The p CA content of alkaline hydrogen peroxide pretreated grasses, proportional to lignin content, was negatively related with enzymatic digestibility (Li et al, 2012).…”

Expression of a bacterial 3‐dehydroshikimate dehydratase reduces lignin content and improves biomass saccharification efficiency

“…Lignocellulosic biomass is used for pulp and paper manufacture, ruminant livestock feeding, and more recently has been considered an important source of simple sugars for fermentative production of intermediate or specialty chemicals and biofuels (Keasling, 2010). It is well-documented that lignin in plant biomass negatively affects pulp yield, forage digestibility and polysaccharide saccharification Chen and Dixon, 2007;Taboada et al, 2010). This has prompted major interest in developing a better understanding of lignin biosynthesis to reduce biomass recalcitrance by modifying lignin content and/or composition.…”