| Abstract | Background: This paper assesses the feasibility of a single- or multi-stage process entirely based on microbial cultures, with no or minimal non-biological pretreatment and with no external enzyme addition, for the conversion of lignocellulosic materials into ethanol. The process considered involves three distinct microbial processes, which can possibly combined in one single reaction stage: (a) lignin hydrolysis; (b) cellulose and hemicelluloses hydrolysis; and (c) glucose fermentation to ethanol. This paper critically reviews the literature on the three microbial processes and compares the rates of microbial processes with those of the alternative physico-chemical pretreatment processes. Results: There is a large number of microbial species that can perform each of the three processes required for the conversion of lignocellulosic biomass to ethanol, although only one species has been unquestionably reported, so far, to be able to hydrolyse lignin under anaerobic conditions; another challenge is controlling the anaerobic fermentation of glucose to ethanol with mixed cultures; the rates of the microbial processes reported so far in the literature are generally lower than the rates obtained with physico-chemical pretreatments. Conclusions: While in principle the whole process from lignocellulosic biomass to bioethanol can be carried out with existing, non-engineered microorganisms, there is a need for further research to obtain rates and yields which are commercially attractive. |
| Text | 300469 2015 10.1002/jctb.4544 Scopus 2 s2.0 84907718639 Bioethanol Cellulose Lignin Microbial hydrolysis Mixed cultures The potential of microbial processes for lignocellulosic biomass conversion to ethanol A review Dionisi, Davide; Anderson, James A.; Aulenta, Federico; McCue, Alan J.; Paton, Graeme Materials and Chemical Engineering Group, School of Engineering, University of Aberdeen, Aberdeen, AB24 3UE, UK; Surface Chemistry and Catalysis Group, School of Natural and Computing Sciences, University of Aberdeen, Aberdeen, AB24 3UE, UK; Water Research Institute, National Research Council CNR IRSA , Via Salaria km 29.300 C.P. 10, 00015, Monterotondo RM , Italy; Department of Plant and Soil Science, University of Aberdeen, Cruickshank Building, St. Machar Drive, Aberdeen, AB24 3UU, UK; Background This paper assesses the feasibility of a single or multi stage process entirely based on microbial cultures, with no or minimal non biological pretreatment and with no external enzyme addition, for the conversion of lignocellulosic materials into ethanol. The process considered involves three distinct microbial processes, which can possibly combined in one single reaction stage a lignin hydrolysis; b cellulose and hemicelluloses hydrolysis; and c glucose fermentation to ethanol. This paper critically reviews the literature on the three microbial processes and compares the rates of microbial processes with those of the alternative physico chemical pretreatment processes. Results There is a large number of microbial species that can perform each of the three processes required for the conversion of lignocellulosic biomass to ethanol, although only one species has been unquestionably reported, so far, to be able to hydrolyse lignin under anaerobic conditions; another challenge is controlling the anaerobic fermentation of glucose to ethanol with mixed cultures; the rates of the microbial processes reported so far in the literature are generally lower than the rates obtained with physico chemical pretreatments. Conclusions While in principle the whole process from lignocellulosic biomass to bioethanol can be carried out with existing, non engineered microorganisms, there is a need for further research to obtain rates and yields which are commercially attractive. 90 Published version http //www.scopus.com/record/display.url eid=2 s2.0 84907718639 origin=inward Articolo in rivista Published for the Society of Chemical Industry by Blackwell Scientific Publications, 0268 2575 Journal of chemical technology and biotechnology 1986 Journal of chemical technology and biotechnology 1986 J. chem. technol. biotechnol. 1986 Journal of chemical technology and biotechnology. 1986 federico.aulenta AULENTA FEDERICO TA.P02.031.001 Impatto dei cambiamenti climatici sulla gestione delle risorse idriche |
