(547f) Applying Partial Least Square (PLS) to Quantify Lignin and Carbohydrates Content of Lignocellulose



Analytical chemistry is often employed to measure lignin and carbohydrates content of lignocellulose. Most traditionally used methods are long,  comprise a large number of steps, are intensive in reactants use, require highly sophisticated equipment such as HPLC and most of the time result in a large standar deviation for replicates. If a large set of data is required, for example when determining kinetic parameters of pretreatment, this method is an important limitation.

Partial Least Square (PLS) combined with Near Infrared Spectroscopy (NIR) was used to determine lignin and carbohydrates content of lignocellulose in solid phase. A calibration curve was obtained using about 100 samples of lignocellulosic material with different lignin and carbohydrates content. An ample spectrum of lignin and carbohydrates contents was attained by using different degrees of maturity and plant parts, as well as by some modifications on the lignocellulose compositional structure through the application of different types of pretreatment. The method was shown succesful to quantify lignin and carbohydrates and much more faster than other traditionally used methods. However, an important limitation is the need to obtain a new calibration curve for each type of biomass used.