Production from Lignocellulose

The comparatively inefficient hydrolysis of cellulosic substrates in pre-treated lignocellulosic biomass is partly due to obstruction by lignin of enz mie access to catalytically productive cellulose binding. 

The activity of cellulases for hydrolysis of the lignocellulose can be improved when weak lignin-binding enz5rmes are used. Certain naturally occurring cellulases differ significantly in their affinities for lignin (33). 

The location and the structure of lignin affects the enzymatic hydrolysis much more than the absolute quantities of lignin. The modification of the lignin surface by oxidative treatments with laccase and a delignification treatment results in an increased hydrolysis of the lignocellulose (34). 

An approach to reduce the deleterious effects of lignin is delignification of pre-treated UgnoceUulosic biomass. Another approach is the introduction of additives to hydrolysis mixtures, including surfactants, proteins and other lignin-binding polymers. In particular, poly (ethylene glycol) has been foxmd to be effective (32). 

Hydrolysis mixtures prepared using high dry matter content, in the presence of PEG and surfactant, can be readily used in simult- 

---

A unique pilot plant for ethanol production from lignocellulose feedstock was inaugurated in O-vik, Sweden in May 2004. The aim of the pilot plant was to develop efficient continuous technologies for the various process steps in ethanol production from forest raw material and other lignocellulosic feedstock. Different raw materials require different conditions during the production process and the process also needs to be optimised for every raw material. Further it was important to demonstrate that large-scale lignocellulose ethanol production was possible... 

Zaldivar, J., Nielsen, J., and Olsson, L. Fuel ethanol production from lignocellulose a challenge for metabolic engineering and process integration. Appl. Microbiol. Biotechnol. 56 17-34 (2001). 

Ingram, L.O. Lai, X. Moniruzzaman, M. Wood, B.E. York, S.W. Fuel ethanol production from lignocellulose using genetically engineered bacteria. In Fuels and Chemicals from Biomass, American Chemical Society Symposium Series Saha, B.C., Woodward, J.E., Eds. American Chemical Society Press Washington, DC, 1997 Vol. 666, 57-73. 

Now the bioethanol is a dominant biofuel and the demand for the bioethanol continues to increase steadily for several decades [1]. To overcome the shortage of raw material, the technology developments for bioethanol production from lignocellulosic biomass have been carried out intensively. Since the collection cost of the wood biomass is too high in Korea,... 

Gurrently, bioethanol is the main product produced from lignocellulosic feedstock. The process of bioethanol production from lignocellulose is currently tested in pilot plants in different countries all over the world, and according to Tan et al. [23] it is consisting of the following steps as discussed next (see Figure 5.6). 

Figure 5.6 Bioethanol production from lignocellulosic biomass (according to Tan [23]).

Wyman CE. (1995). Economic fundamentals of ethanol production from lignocellulosic biomass. In Saddler JN, Penner MH, editors. Enzymatic, Degradation of Insoluble Carbohydrates. Washington, DC American Chemical Society, pp. 272-290. 

Many well-financed technology development companies are actively pursuing scale-up and commercialization of variations of enzymatic hydrolysis technology for specific pretreated biomass feedstocks. Within the next several years, it is anticipated that enzymatic hydrolysis technologies, as practiced by these companies, will be contributing to commercial production of a range of biofuels and chemical products from lignocellulosic feedstocks. 

Fujitomi K, Sanda T, Hasunuma T, Kondo A. (2012). Deletion of the PH013 gene in Sac-charomyces cerevisiae improves ethanol production from lignocellulosic hydrolysate in the presence of acetic and formic acids, and furfural. Bioresour Technol, 111, 161-166. 

Stryer, L. Biochemistry W.H. Freeman and Company San Francisco, 1981. Wyman, CJE. Goodman, B.J. Near Term Application of Biotechnology to Fuel Ethanol Production from Lignocellulosic Biomass NIST GCR 93-63 U.S. Department of Commerce Washington, D.C., 1993. 

Figure 5.6 Overview of accessible products from lignocellulose by Ragauskas etal. ...

Value-Added Products from Lignocellulosic Biomass Pyrolysis... 

Abdel-Rahman MA, Tashiro Y, Sonomoto K. Lactic acid production from lignocellulose-derived sugars using lactic acid bacteria overview and limits. J Biotechnol 2011 156 286-301. 

Model for Ethanol Production from Lignocellulosic Raw Materials... 

---