Biofuel: the impact of lignins

Biofuel: the impact of lignins

Mastering a key stage of lignification increases the yield of fermentable sugars by 140%.

The plant cell wall is composed of polysaccharides that are a source of energy for animals and humans. However, the stem walls of plants are also soaked with lignins, complex phenolic compounds that inhibit biorefinery saccharification.

The saccharification process refers to the production of simple and fermentable sugars, from polysaccharides such as cellulose, through the activity of biomass degradation enzymes. This is a prerequisite for the production of ethanol by fermentation.

In order to optimize bioethanol production from grasses, researchers are working on a model species, related to wheat and barley, Brachypodium distachyon.

This study, the result of an international collaboration, demonstrated that by reducing the activity of two laccases (enzymes involved in lignin production), the saccharification yield could be increased by 140% in this species.

This work has also shown that the decrease in laccase activity is accompanied by a decrease in lignin content but does not significantly affect the development of the plant; this is a crucial point for the transfer of this knowledge to other field crop species. The same laccases have been identified in species such as rice and maize.

It would therefore now be possible, by the varietal selection, to consider plants with reduced laccase activities, with fewer lignins, more suitable for biofuel production.


See also

Related publication: Le Bris P, Wang Y, Barbereau C, Antelme S, Cezard L, Legee F, D'Orlando A, Dalmais M, Bendahmane A, Schuetz M, et al. 2019. Inactivation of LACCASE8 and LACCASE5 genes in Brachypodium distachyon leads to severe decrease in lignin content and high increase in saccharification yield without impacting plant integrity. Biotechnol Biofuels 12: 181.

Modification date : 11 September 2023 | Publication date : 04 November 2019 | Redactor : M Weber