Concluding remarks: where do we stand and where are we going? Lignin biodegradation and practical utilization.

The progress made in the efforts to develop biotechnology based on lignocellulosic materials is discussed in some detail. It is appreciated that biotechnical conversion of lignocellulosics means production of inexpensive products on a large scale and is therefore a more difficult task than development of biotechnology in medicine and pharmacology, i.e. production of expensive products on a small scale. However, the massive efforts devoted over the past few decades to a better understanding of the enzyme mechanisms involved in degradation of wood components have not been in vain. The literature base so essential for successful application of biotechnology to conversion of lignocellulosic materials is now in place. The article presents a summary of our knowledge of the enzyme mechanisms involved in the degradation of the three main lignocellulosic components. It also tries to evaluate in which important areas we lack the necessary information to apply biotechnology, particularly in the pulp and paper industry.