Separation and structure analysis of switchgrass lignin

Switchgrass(Panicum virgatum) is a herbaceous plant which is a good potential biomass for bioethanol. The paper conducted the ball mill isolating and purifying method to study the native lignin structure of four different varieties of switchgrasses with 13C NMR spectroscopic technique. In addition, acid insoluble lignin and soluble lignin content were measured. The result showed that the lignin of four varieties contained three elements, such as Hmetahydroxyphenyl, Gguaiacol, and Syringyl lignin. The content of acid insoluble lignin was 20%-23%, and the soluble lignin content was 2%-3%. Their ball milling lignin structure and lignin contents were similar among the 4 varieties, indicating switchgrass lignin structure and content were relatively stable.