Authors: Wipaporn Kuntiyou and Wiyada Mongkolthanaruk
Abstract: The objective of this study was investigation of the method for measuring the degradation of lignin in agricultural materials. Three methods, prussian blue color method, acetyl bromide soluble lignin (ABSL) method and nitrate lignin method, were investigated using alkali lignin as a standard compound. All 3 methods showed the accuracy of measuring the amount of lignin with R2 of 0.97-0.99. However, the method detected the lignin digestion was suitable to determine lignin released in the liquid; the nitrate lignin method was selected to use in further study. The rice straw treated with heat still contained lignin in the materials, while it treated with alkali could digest lignin in the materials. Burkholderia cepacia AB2.2 showed effectively digestion to remove lignin from the rice straw treated with heat. Most bacteria could remove lignin from the rice straw treated with alkali, particularly Chitinophaga sp. CHU1/4-1.2. The bacterial activity was able to digest lignin in agricultural materials.
Keywords: lignin degradation; bacterial activity; nitrate lignin method