Despite the fact that lignin has been analysed for quite some time, it is still a considerable challenge to map the branches properly. An American-Flemish team found a mass spectrometry method that has made this a whole lot easier.

Lignin, a main component of the cell walls of plant tissues such as wood, is an aromatic polymer that is partly linear and partly branched. It is composed mainly of guaiacyl and syringyl units, but can also contain other types of phenolic units. If you want to know the shape of such a polymer, you can break it into pieces and analyse it with mass spectrometry (MS). ‘Analysing lignin with MS has been going on for quite a long time’, says Kris Morreel, visiting professor at UGent and senior scientist at RIC Group. ‘But some oligomeric fragments that occur infrequently are difficult to identify. Yet that analysis is important to pinpoint branches in the sequence.’ Naturally, if you don’t know what you’re dealing with, you can’t do anything with it.