Use of lytic polysaccharide monooxygenases (LPMO) to enhance the enzyme treatment for cellulose nano-fibrils (CNF) preparation

这一合作研究项目将由新不伦瑞克大学的倪永浩博士和他的团队与Domtar Inc.合作进行。内切葡聚糖酶和外切葡聚糖酶等纤维素酶已经显示出促进精炼和纤化的能力，并且通过纤维素预处理步骤，可以降低纳米纤维素生产中的总能耗(例如。NFC)。然而，纤维素酶的作用在打破原纤维间的粘合/原纤化方面通常不是特定的，纤维的缩短是不可避免的，特别是在NFC生产过程中所要求的强纤维素酶处理条件下。拟议研究的总体策略使用辅助酶/蛋白质，如溶解多糖单加氧酶(LPMO)来提高纤维素酶的性能，特别是有利于对纤颤的特异性。这将导致低成本纤维素酶/辅酶/蛋白质前处理技术的发展，以大幅降低NFC生产中的能源消耗。加拿大纸浆和造纸行业面临着激烈的国际竞争。这项关于纳米纤维素产品的研究结果不仅将使工业合作伙伴Domtar受益，也将使其他加拿大纸浆和造纸公司受益。具体内容/交付成果包括：1)研究漂白硫酸盐纸浆纤维在LPMO强化酶处理下的原纤化反应，包括精炼能量、宽度、长度、纵横比及其分布，以及在优化工艺条件下的CNF的机械强度性能。2)确定了LPMO强化漂白硫酸盐浆纤维酶前处理的基本原理。3)开发新的、成本效益高、环境友好的LPMO强化酶法制备漂白硫酸盐浆生产高质量的CNF产品。

This collaborative research project will be undertaken by Dr. Yonghao Ni and his team at the University of New Brunswick, in partnership with Domtar Inc. Cellulases such as endoglucanase and exoglucanase have shown the ability to facilitate refining and fibrillation, and with a cellulose pretreatment step, allows the total energy consumption to be lowered in the production of nano-cellulose (eg. NFC). However the cellulose action is usually not specific in breaking the inter-fibril bonding/fibrillation, and fiber shortening is inevitable, particularly under strong cellulase treatment conditions which are required in the NFC production process. The overall strategy of the proposed research uses accessory enzymes/proteins such as lytic polysaccharide monooxygenases (LPMO) to boost cellulase performance, in particular favouring the specificity towards fibrillation. This will lead to the development of cost effective cellulase/accessory enzymes/proteins pretreatment technology to substantially decrease the energy consumption in NFC production. The Canadian pulp and paper industry faces strong international competition. The results from this research in relation to nanocellulose products will benefit not only Domtar, the industrial partner but also other Canadian pulp and paper companies. Details/deliverables include: 1) Investigation of the fibrillation response of bleached kraft pulp fibers to LPMO enhanced enzymatic treatment in terms of refining energy, width, length, aspect ratio and their distribution of the resultant cellulose nanofibrils (CNF), as well as mechanical strength properties of the CNF's with optimized process conditions. 2) Determine the fundamentals of LPMO enhanced enzymatic pretreatment of bleached kraft pulp fibers. 3) Develop novel, cost effective and environmentally friendly LPMO enhanced exnymatic processes for the production of high quality CNF product from bleached kraft pulps.