Bioethanol Fermentation from Untreated and Pretreated Bagasse Using Fusarium oxysporum
01 Mar 2011-Indian Chemical Engineer (Taylor & Francis Group)-Vol. 53, Iss: 1, pp 18-32
TL;DR: In this paper, the authors compared the performance of pretreated bagasse with dilute alkaline peroxide and steam for bioethanol production by simultaneous saccharification and fermentation (SSF) process in a continuous stirred batch bioreactor using fungi Fusarium oxysporum.
Abstract: Comparisons were studied for untreated and pretreated bagasse with dilute alkaline peroxide and steam for bioethanol production by simultaneous saccharification and fermentation (SSF) process in a continuous stirred batch bioreactor using fungi Fusarium oxysporum. The optimum parameters for bioethanol fermentation were: time, 48 h; pH, 6.0; temperature, 50°C; stirring speed, 35 rpm; and bagasse loading, 35 g/L. Maximum concentrations of bioethanol at optimum fermentation process parameters were 18.73 g/L, 19.69 g/L and 20.45 g/L for untreated, steam and dilute alkaline peroxide pretreated bagasse, respectively. Maximum yields of bioethanol were 0.706 g/g, 0.734 g/g and 0.764 g/g of bagasse at optimum parameters for untreated, steam and dilute alkaline peroxide pretreated bagasse, respectively. The sp. growth rate (µ) of fungi Fusarium oxysporum was determined at 5.91 s−1, 6.25 s−1 and 7.11 s−1 and maximum sp. growth rate (µmax) was calculated at 11.81 s−1, 12.50 s−1 and 14.22 s−1 for untreated, s...
TL;DR: In this paper, the potential of six lignocellulosic biomass (LCB) sources; namely, sugarcane bagasse (BG), cassava aerial parts (CS), ficus fruits (Ficus cunia) (FF), Phumdi (floating biomass) (PH), rice straw (RS) and sawdust (SD) were investigated for bioethanol production using standard techniques.
Abstract: Vegetation biomass production in North-East India within Indo-Burma biodiversity hotspot is luxuriant and available from April to October to consider their potential for bioethanol production. Potential of six lignocellulosic biomass (LCB) sources; namely, sugarcane bagasse (BG), cassava aerial parts (CS), ficus fruits (Ficus cunia) (FF), ‘phumdi’ (floating biomass) (PH), rice straw (RS) and sawdust (SD) were investigated for bioethanol production using standard techniques. Morphological and chemical changes were evaluated by Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy and quantity of sugars and inhibitors in LCB were determined by High performance liquid chromatography (HPLC). Hydrothermally treated BG, CS and FF released 954.54, 1354.33 and 1347.94 mg/L glucose and 779.31, 612.27 and 1570.11 mg/L of xylose, respectively. Inhibitors produced due to effect of hydrothermal pretreatment ranged from 42.8-145.78 mg/L acetic acid, below detection level (BDL) to 17.7 µg/L 5-hydroxymethylfurfural (HMF) and BDL to 56.78 µg/L furfural. The saccharification efficiency of hydrothermally treated LCB (1.35-28.64%) was significantly higher compared to their native counterparts (0.81-17.97%). Consolidated bioprocessing (CBP) of the LCB using MTCC 1755 (Fusarium oxysporum) resulted in maximum ethanol concentration of 0.85 g/l and corresponded to 42 mg ethanol per g of hydrothermally treated BG in 120 hrs followed by 0.83 g/L corresponding to 41.5 mg/g of untreated CS in 144 hrs. These ethanol concentrations corresponded to 23.43% and 21.54% of theoretical ethanol yield, respectively. LCB of CS and FF emerged as a suitable material to be subjected to test for enhanced ethanol production in future experiments through efficient fermentative microbial strains, appropriate enzyme loadings and standardization of other fermentation parameters.
Cites background from "Bioethanol Fermentation from Untrea..."
TL;DR: In this article , the influence of stirring speed on the glucose and ethanol concentration in simultaneous saccharification and fermentation (SSF) process was investigated in Malaysia, where empty fruit bunches (EFB) is one of the most abundant lignocellulosic biomass in Malaysia.
Abstract: Lignocellulosic biomass has a potential to be coverted to bioethanol which can be a new alternative for fossil fuel. Empty fruit bunches (EFB) is one of the most abundant lignocellulosic biomass in Malaysia, which has high content of cellulose and posses favorable physiochemical characteristics for bioethanol production via a process called simultaneous saccharification and fermentation (SSF). In SSF process, the reaction is initiated by diffusion and consolidation of the enzyme and its substrate. Thus, optimum stirring speed is crucial, as diffusion rate of substrates is influenced by the agitation of reaction mixture. The influence of stirring speed on the glucose and ethanol concentration in SSF process was investigated in the current study. Initially, 5 % (g/ml) of pretreated EFB in 1.5 liter of 0.05 M buffer citrate pH 4.8 were sterilized in autoclave at 121°C for 20 minutes. Then, enzyme Cellic Ctec-2 solution with concentration (1%) were added together with 1.5% (g/ml) Saccharomyces cerevisiae yeast in the bioreactor. The process was conducted in the bioreactor under temperature of 37°C with stirring speed of 100 rpm for 72 hours. SSF process experiments were repeated with the same setup except by varying the stirring speed (150 and 200 rpm) independently. From the results, the glucose concentration and ethanol yield of 200 rpm indicated less concentration in every 24 hours compared to 150 rpm and 100 rpm. The stirring speed of 150 rpm shows the highest glucose concentration (1.914 mg/ml) and ethanol yield (16%) obtained after 72 hours and determined as the best stirring speed for this experiment.
30 Jun 1972
TL;DR: An overview of Chemical Reaction Engineering is presented, followed by an introduction to Reactor Design, and a discussion of the Dispersion Model.
Abstract: Partial table of contents: Overview of Chemical Reaction Engineering. HOMOGENEOUS REACTIONS IN IDEAL REACTORS. Introduction to Reactor Design. Design for Single Reactions. Design for Parallel Reactions. Potpourri of Multiple Reactions. NON IDEAL FLOW. Compartment Models. The Dispersion Model. The Tank--in--Series Model. REACTIONS CATALYZED BY SOLIDS. Solid Catalyzed Reactions. The Packed Bed Catalytic Reactor. Deactivating Catalysts. HETEROGENEOUS REACTIONS. Fluid--Fluid Reactions: Kinetics. Fluid--Particle Reactions: Design. BIOCHEMICAL REACTIONS. Enzyme Fermentation. Substrate Limiting Microbial Fermentation. Product Limiting Microbial Fermentation. Appendix. Index.
TL;DR: Steam pretreatment, lime pret treatment, liquid hot water pretreatments and ammonia based Pretreatments are concluded to be pretreatment with high potentials, providing an improved accessibility of the cellulose for hydrolytic enzymes.
Abstract: Lignocellulosic biomass represents a rather unused source for biogas and ethanol production. Many factors, like lignin content, crystallinity of cellulose, and particle size, limit the digestibility of the hemicellulose and cellulose present in the lignocellulosic biomass. Pretreatments have as a goal to improve the digestibility of the lignocellulosic biomass. Each pretreatment has its own effect(s) on the cellulose, hemicellulose and lignin; the three main components of lignocellulosic biomass. This paper reviews the different effect(s) of several pretreatments on the three main parts of the lignocellulosic biomass to improve its digestibility. Steam pretreatment, lime pretreatment, liquid hot water pretreatments and ammonia based pretreatments are concluded to be pretreatments with high potentials. The main effects are dissolving hemicellulose and alteration of lignin structure, providing an improved accessibility of the cellulose for hydrolytic enzymes.
TL;DR: The different technologies for producing fuel ethanol from sucrose-containing feedstocks (mainly sugar cane, starchy materials and lignocellulosic biomass) are described along with the major research trends for improving them.
Abstract: Present work deals with the biotechnological production of fuel ethanol from different raw materials. The different technologies for producing fuel ethanol from sucrose-containing feedstocks (mainly sugar cane), starchy materials and lignocellulosic biomass are described along with the major research trends for improving them. The complexity of the biomass processing is recognized through the analysis of the different stages involved in the conversion of lignocellulosic complex into fermentable sugars. The features of fermentation processes for the three groups of studied feedstocks are discussed. Comparative indexes for the three major types of feedstocks for fuel ethanol production are presented. Finally, some concluding considerations on current research and future tendencies in the production of fuel ethanol regarding the pretreatment and biological conversion of the feedstocks are presented.
TL;DR: This review gives an overview of the new technologies required and the advances achieved in recent years to bring lignocellulosic ethanol towards industrial production.
Abstract: The increased concern for the security of the oil supply and the negative impact of fossil fuels on the environment, particularly greenhouse gas emissions, has put pressure on society to find renewable fuel alternatives. The most common renewable fuel today is ethanol produced from sugar or grain (starch); however, this raw material base will not be sufficient. Consequently, future large-scale use of ethanol will most certainly have to be based on production from lignocellulosic materials. This review gives an overview of the new technologies required and the advances achieved in recent years to bring lignocellulosic ethanol towards industrial production. One of the major challenges is to optimize the integration of process engineering, fermentation technology, enzyme engineering and metabolic engineering.
TL;DR: Wheat straw biorefinery could be the near-term solution for clean, efficient and economically-feasible production of bioethanol as well as high value-added products.
Abstract: Wheat straw is an abundant agricultural residue with low commercial value. An attractive alternative is utilization of wheat straw for bioethanol production. However, production costs based on the current technology are still too high, preventing commercialization of the process. In recent years, progress has been made in developing more effective pretreatment and hydrolysis processes leading to higher yield of sugars. The focus of this paper is to review the most recent advances in pretreatment, hydrolysis and fermentation of wheat straw. Based on the type of pretreatment method applied, a sugar yield of 74-99.6% of maximum theoretical was achieved after enzymatic hydrolysis of wheat straw. Various bacteria, yeasts and fungi have been investigated with the ethanol yield ranging from 65% to 99% of theoretical value. So far, the best results with respect to ethanol yield, final ethanol concentration and productivity were obtained with the native non-adapted Saccharomyses cerevisiae. Some recombinant bacteria and yeasts have shown promising results and are being considered for commercial scale-up. Wheat straw biorefinery could be the near-term solution for clean, efficient and economically-feasible production of bioethanol as well as high value-added products.