A supplement to the research of native lignin of beech sapwood (Fagus sylvatica L.)

Native or Brauns lignin (NL) isolated with ethanol extraction from beech sapwood ( Fagus sylvatica L.) was studied with the purpose of researching its structure and chemical properties. Modifi ed Brauns method was applied for native lignin isolation, which is diff erent from original in disregarding purifi cation processes with successive and repetitive precipitation of the dioxane solution into water and into ether. Furthermore, native lignin (NL) was studied using ultraviolet (UV) and Fourier transform infrared (FTIR) spectroscopic techniques of analysis. Availability for structural studies of GS lignins with spectral characterisation of modifi ed NL isolation method was proved. Diff erences in spectroscopic behaviour between in this work obtained native lignins (NL) and milled wood lignins (MWL) from previous studies were determined using both spectroscopic technics.