Biotechnology of Biopolymers and Bioactive Compounds Special Research Unit, Department of Biotechnology, Faculty of Agro-Industry, Kasetsart University, Chatuchak, Bangkok 10900, Thailand.
Enzyme Technology Laboratory, Bioresources Technology Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, Pathum Thani 12120, Thailand.
Int J Biol Macromol. 2019 Feb 1;122:503-516. doi: 10.1016/j.ijbiomac.2018.10.191. Epub 2018 Oct 30.
A two-stage pretreatment process using alkaline and xylanase-assisted pretreatments was studied and compared to one-step alkaline pretreatment to investigate the effect of xylanase-assisted pretreatments on the properties of fibers and regenerated cellulose films. The alkaline-xylanase bleached fibers (AXB-fibers) could reduce bleaching time from 6 to 4 times to obtain an 83.3% whiteness index. A substantial proportion of the cellulose content (83%) was successfully extracted from sugarcane bagasse using the two-step process. Moreover, the fiber had an increased crystallinity index and thermal stability. Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) revealed that hemicellulose and lignin were removed from the sugarcane bagasse (SCB) structure during the cellulose extraction process. The alkaline bleached fibers (AB-fibers) and AXB-fibers were dissolved in 1-butyl-3-methylimidazolium chloride, and regenerated cellulose films, AB-films and AXB-films, respectively, were prepared from the solutions. SEM images showed that both cellulose films were homogeneous and had a smooth surface. FTIR and X-ray diffraction (XRD) analyses corroborated that the transition from cellulose I to cellulose II occurred during the dissolution and regeneration process. Furthermore, the AXB-films displayed higher thermal stability and mechanical properties (258 °C and 90.43 MPa for the onset temperature and tensile strength, respectively) than those of the AB-films.
采用碱性和木聚糖酶辅助预处理的两阶段预处理工艺进行了研究，并与一步碱性预处理进行了比较，以研究木聚糖酶辅助预处理对纤维和再生纤维素膜性能的影响。碱性-木聚糖酶漂白纤维（AXB-纤维）可以将漂白时间从 6 次减少到 4 次，以获得 83.3%的白度指数。使用两步法可以从甘蔗渣中成功提取出 83%的纤维素含量。此外，纤维的结晶度指数和热稳定性都有所提高。傅里叶变换红外（FTIR）光谱和扫描电子显微镜（SEM）表明，在纤维素提取过程中，半纤维素和木质素从甘蔗渣（SCB）结构中被去除。碱性漂白纤维（AB-纤维）和 AXB-纤维溶解在 1-丁基-3-甲基咪唑氯化物中，分别从溶液中制备出再生纤维素膜 AB-膜和 AXB-膜。SEM 图像表明，两种纤维素膜均均匀且表面光滑。FTIR 和 X 射线衍射（XRD）分析证实，在溶解和再生过程中，纤维素 I 向纤维素 II 的转变发生。此外，AXB-膜的起始温度和拉伸强度分别为 258°C 和 90.43 MPa，显示出比 AB-膜更高的热稳定性和机械性能。
