| Autor: |
Riyadi FA; Department of Chemical Engineering, Faculty of Engineering, Universitas Indonesia.; Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia., Azman NF; Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia., Nadia Md Akhir F; Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia., Othman N; Department of Mechanical Precision Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia., Hara H; Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia.; Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo. |
| Abstrakt: |
Biological pretreatment using microbial enzymes appears to be the most promising pre-treatment technology for the breakdown of recalcitrant lignin structure. This research focuses on the identification and characterization of lignin-depolymerizing enzymes in Bacillus subtilis strain S11Y, previously isolated from palm oil wastes in Malaysia. The draft genome sequences of this highly lignin-depolymerizing strain revealed that the genome lacked any of the well-known dye-decolorizing peroxidase or catalase-peroxidase that are commonly reported to be involved in lignin depolymerization by bacteria, indicating that strain S11Y has distinct sets of potential lignin depolymerization genes. The oxidative stress-related enzymes Cu/Zn type-superoxide dismutase (Sod2) and a heme-containing monofunctional catalase (Kat2) were identified in the genome sequences that are of interest. Their lignin-depolymerizing ability were evaluated by treating Alkali lignin (AL) with each enzyme and their degradation ability were evaluated using gel-permeation chromatography (GPC), ultrahigh-pressure liquid chromatography-mass spectrometry (UHPLC/MS), and gas chromatography-mass spectrometry (GC/MS), which successfully proved lignin depolymerizing ability. Successful evaluation of lignin depolymerizing enzymes can be applicable for lignin pretreatment process in green energy production and generation of valuable chemicals in bio-refinery. |
