The Beatability-aiding Effect of Aspergillus niger Crude Cellulase on Bleached Simao Pine Kraft Pulp and its Mechanism of Action

Zheng-Jian Zhang, Yun-Zhi Chen, Hui-Ren Hu, Yi-Zhou Sang

Abstract


Bleached simao pine kraft pulp was treated with Aspergillus niger crude cellulase produced by submerged fermentation using the pulp as the carbon source. The effects of the cellulase on the pulp beatability and mechanical properties were studied. Fourier transform infrared spectroscopy (FT-IR) was performed to study the effect of cellulase treatment on the cellulose crystallinity index. The fiber morphology difference before and after treatment was also revealed by atomic force microscope observation. Compared to the control pulp, the beating time of the cellulase-treated pulp with the dosage of 7 u/g could be reduced from 360 s to 260 s under the same beating degree of 48oSR, which indicates a savings of about 28% beating energy consumption. The cellulase treatment had negative impacts on the pulp’s mechanical properties. The cellulase preferentially adsorbed on the fine surface. The cellulose amorphous region was easier to treat with cellulase than the crystalline region. Atomic force microscope images demonstrated that the primary wall of fibers was peeled off and the S1 layer of fibers came to the surface after the cellulase treatment.

Keywords


Aspergillus niger; Cellulase; Beatability; Action mechanism; Bleached simao pine kraft pulp

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Welcome to BioResources! This online, peer-reviewed journal is devoted to the science and engineering of biomaterials and chemicals from lignocellulosic sources for new end uses and new capabilities. The editors of BioResources would be very happy to assist you during the process of submitting or reviewing articles. Please note that logging in is required in order to submit or review articles. Martin A. Hubbe, (919) 513-3022, hubbe@ncsu.edu; Lucian A. Lucia, (919) 515-7707, lucian.lucia@gmail.com URLs: bioresourcesjournal.com; http://ncsu.edu/bioresources ISSN: 1930-2126