scholarly journals Bioethanol Production From Pineapple Wastes

2014 ◽  
Vol 3 (4) ◽  
pp. 60 ◽  
Author(s):  
Alessia Tropea ◽  
David Wilson ◽  
Loredana G. La Torre ◽  
Rosario B. Lo Curto ◽  
Peter Saugman ◽  
...  
Keyword(s):  
Plant Cell ◽  
Cell Walls ◽  
Simultaneous Saccharification And Fermentation ◽  
Ethanol Yield ◽  
Enzymatic Saccharification ◽  
Plant Cell Walls ◽  
Theoretical Yield ◽  
Cellulosic Sugars ◽  
Separate Hydrolysis And Fermentation ◽  
Simultaneous Saccharification

<p>There is great interest in producing bioethanol from biomass and there is much emphasis on exploiting lignocellulose sources, from crop wastes through to energy-rich crops. Some waste streams, however, contain both cellulosic and non-cellulosic sugars. These include wastes from pineapple processing.</p> <p>Pineapple wastes are produced in large amounts throughout the world by canning industries. These wastes are rich in intracellular sugars and plant cell walls which are composed mainly of cellulose, pectic substances and hemicelluloses. The purpose of this study was to investigate the potential to transform such residues into ethanol after enzymatic saccharification of plant cell walls, and fermentation of the resulting simple sugars using the <em>Saccharomyces cerevisiae</em> NCYC 2826 strain. Three different fermentation modes, direct fermentation, separate hydrolysis and fermentation, and simultaneous saccharification and fermentation of the biomass were tested and compared. The results show that the main sugars obtained from pineapple waste were: glucose, uronic acid, xylose, galactose, arabinose and mannose. The highest ethanol yield was achieved after 30 hours of simultaneous saccharification and fermentation, and reached up to 3.9% (v/v), corresponding to the 96% of the theoretical yield.</p>

EVALUATION OF WASTE MUSHROOM MEDIUM AS A FERMENTABLE SUBSTRATE AND BIOETHANOL PRODUCTION

2012 ◽  
Vol 06 ◽  
pp. 745-750
Author(s):  
AI ASAKAWA ◽  
CHIZURU SASAKI ◽  
CHIKAKO ASADA ◽  
YOSHITOSHI NAKAMURA
Keyword(s):  
Steam Explosion ◽  
Lentinula Edodes ◽  
Simultaneous Saccharification And Fermentation ◽  
Ethanol Yield ◽  
Enzymatic Saccharification ◽  
Steam Pressure ◽  
Insoluble Residue ◽  
Steam Explosion Pretreatment ◽  
Simultaneous Saccharification ◽  
Waste Mushroom Medium

Waste Shiitake (Lentinula edodes) mushroom medium, a lignocellulosic aglicultural residue, was evaluated as a fermentable substrate. 87% of the fermentable sugars remained in the waste mushroom medium. The sugar yield of the waste mushroom medium (46.3%) was higher than that of raw mushroom medium (20.3%) after 48 h of enzymatic saccharification by Meicelase because L. edodes changed wood structure. These results indicated that the waste mushroom medium is a suitable substrate for fermentation. Next, the efficient ethanol production using steam explosion pretreatment was studied. After 30 h of simultaneous saccharification and fermentation (SSF) using Meicelase and Saccharomyces cerevisiae AM12, 20.0 g/L ethanol was produced from 100 g/L water-insoluble residue of the waste mushroom medium treated at a steam pressure of 20 atm and a steaming time of 5 min. This corresponded to an ethanol yield of 77.0% of the theoretical, i.e. 14.7 g of ethanol obtained from 100 g of waste mushroom medium.

Plant cell walls to ethanol

2012 ◽  
Vol 442 (2) ◽  
pp. 241-252 ◽  
Author(s):  
Douglas B. Jordan ◽  
Michael J. Bowman ◽  
Jay D. Braker ◽  
Bruce S. Dien ◽  
Ronald E. Hector ◽  
...  
Keyword(s):  
Plant Cell ◽  
Cell Walls ◽  
Second Generation ◽  
Consolidated Bioprocessing ◽  
Enzymatic Saccharification ◽  
Crystalline Cellulose ◽  
Plant Cell Walls ◽  
Second Generation Bioethanol ◽  
Single Organism ◽  
The Cost

Conversion of plant cell walls to ethanol constitutes second generation bioethanol production. The process consists of several steps: biomass selection/genetic modification, physiochemical pretreatment, enzymatic saccharification, fermentation and separation. Ultimately, it is desirable to combine as many of the biochemical steps as possible in a single organism to achieve CBP (consolidated bioprocessing). A commercially ready CBP organism is currently unreported. Production of second generation bioethanol is hindered by economics, particularly in the cost of pretreatment (including waste management and solvent recovery), the cost of saccharification enzymes (particularly exocellulases and endocellulases displaying kcat ~1 s−1 on crystalline cellulose), and the inefficiency of co-fermentation of 5- and 6-carbon monosaccharides (owing in part to redox cofactor imbalances in Saccharomyces cerevisiae).

scholarly journals Pretreatment of Corn Stover Using an Extremely Low-Liquid Ammonia (ELLA) Method for the Effective Utilization of Sugars in Simultaneous Saccharification and Fermentation (SSF) of Ethanol

Fermentation ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 191
Author(s):  
Tin Diep Trung Le ◽  
Vi Phuong Nguyen Truong ◽  
My Thi Tra Ngo ◽  
Tae Hyun Kim ◽  
Kyeong Keun Oh
Keyword(s):  
Corn Stover ◽  
Liquid Ammonia ◽  
Elevated Temperatures ◽  
Simultaneous Saccharification And Fermentation ◽  
Aqueous Ammonia ◽  
Ethanol Yield ◽  
Enzymatic Saccharification ◽  
Extended Period ◽  
Pretreatment Conditions ◽  
Simultaneous Saccharification

Extremely low-liquid ammonia (ELLA) pretreatment using aqueous ammonia was investigated in order to enhance the enzymatic saccharification of corn stover and subsequent ethanol production. In this study, corn stover was treated with an aqueous ammonia solution at different ammonia loading rates (0.1, 0.2, and 0.3 g NH3/g biomass) and various liquid-to-solid (L/S) ratios (0.55, 1.12, and 2.5). The ELLA pretreatment was conducted at elevated temperatures (90–150 °C) for an extended period (24–120 h). Thereafter, the pretreated material was saccharified by enzyme digestion and subjected to simultaneous saccharification and fermentation (SSF) tests. The effects of key parameters on both glucan digestibility and xylan digestibility were analyzed using analysis of variance (ANOVA). Under optimal pretreatment conditions (L/S = 2.5, 0.1 g-NH3/g-biomass, 150 °C), 81.2% glucan digestibility and 61.1% xylan digestibility were achieved. The highest ethanol yield achieved on the SSF tests was 85.4%. The ethanol concentration was 14.5 g/L at 96 h (pretreatment conditions: liquid-to-solid ratio (L/S) = 2.5, 0.1 g-NH3/g-biomass, 150 °C, 24 h. SSF conditions: microorganism Saccharomyces cerevisiae (D5A), 15 FPU/g-glucan, CTech2, 3% w/v glucan, 37 °C, 150 rpm).

scholarly journals Production of Bioethanol from Cassava using Zymomonas mobilis: Effect of Temperature and Substrate concentration

2019 ◽  
Vol 1 ◽  
pp. 153-160
Author(s):  
I J Ona ◽  
H O Agogo ◽  
M S Iorungwa
Keyword(s):  
Zymomonas Mobilis ◽  
Simultaneous Saccharification And Fermentation ◽  
Ethanol Yield ◽  
Effect Of Temperature ◽  
Cassava Flour ◽  
Gram Negative ◽  
Theoretical Yield ◽  
Ethanol Yields ◽  
Theoretical Ethanol Yield ◽  
Simultaneous Saccharification

The production of ethanol from cassava flour using Zymomonas mobilis a gram negative bacterium was conducted at 30oC, 33oC, 35oC and 37oC. The fermentation reaction was also carried out at different substrate concentrations; 5% W/V, 7% W/V and 10% W/V. The microorganism Zymomonas mobilis was detected in palm wine, isolated and identified. It was found to be gram negative, oxidase negative, catalase positive, anaerobic and plump rods with an unusual width. Results obtained from the simultaneous saccharification and fermentation reactions carried out with Zymomonas mobilis showed that maximum theoretical ethanol yield of 63% was obtained for 7% W/V cassava flour at 35oC. This was followed by a theoretical yield of 56.23 and 54.12 for 5% W/V and 10% W/V cassava flour, respectively. Fermentations at 30oC and 33 oC gave similar results with 7% W/V cassava producing higher ethanol yield when compared to 5% W/V and 10% W/V. Fermentation reactions at 37oC gave the lowest ethanol yields. The optimum pH for the simultaneous saccharification and fermentation of cassava was found to be pH of 6.

scholarly journals Down-regulation of OsMYB103L distinctively alters beta-1,4-glucan polymerization and cellulose microfibers assembly for enhanced biomass enzymatic saccharification in rice

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Leiming Wu ◽  
Mingliang Zhang ◽  
Ran Zhang ◽  
Haizhong Yu ◽  
Hailang Wang ◽  
...  
Keyword(s):  
Plant Cell ◽  
Cell Walls ◽  
Cellulose Nanofibers ◽  
Enzymatic Saccharification ◽  
Bioenergy Crops ◽  
Cellulose Biosynthesis ◽  
Plant Cell Walls ◽  
Down Regulation ◽  
Rnai Line ◽  
Rice Mutant

Abstract Background As a major component of plant cell walls, cellulose provides the most abundant biomass resource convertible for biofuels. Since cellulose crystallinity and polymerization have been characterized as two major features accounting for lignocellulose recalcitrance against biomass enzymatic saccharification, genetic engineering of cellulose biosynthesis is increasingly considered as a promising solution in bioenergy crops. Although several transcription factors have been identified to regulate cellulose biosynthesis and plant cell wall formation, much remains unknown about its potential roles for genetic improvement of lignocellulose recalcitrance. Results In this study, we identified a novel rice mutant (Osfc9/myb103) encoded a R2R3-MYB transcription factor, and meanwhile generated OsMYB103L-RNAi-silenced transgenic lines. We determined significantly reduced cellulose levels with other major wall polymers (hemicellulose, lignin) slightly altered in mature rice straws of the myb103 mutant and RNAi line, compared to their wild type (NPB). Notably, the rice mutant and RNAi line were of significantly reduced cellulose features (crystalline index/CrI, degree of polymerization/DP) and distinct cellulose nanofibers assembly. These alterations consequently improved lignocellulose recalcitrance for significantly enhanced biomass enzymatic saccharification by 10–28% at p < 0.01 levels (n = 3) after liquid hot water and chemical (1% H2SO4, 1% NaOH) pretreatments with mature rice straws. In addition, integrated RNA sequencing with DNA affinity purification sequencing (DAP-seq) analyses revealed that the OsMYB103L might specifically mediate cellulose biosynthesis and deposition by regulating OsCesAs and other genes associated with microfibril assembly. Conclusions This study has demonstrated that down-regulation of OsMYB103L could specifically improve cellulose features and cellulose nanofibers assembly to significantly enhance biomass enzymatic saccharification under green-like and mild chemical pretreatments in rice. It has not only indicated a powerful strategy for genetic modification of plant cell walls in bioenergy crops, but also provided insights into transcriptional regulation of cellulose biosynthesis in plants.

Exploration of cell wall architecture with the rapid-freeze deep-etch technique

1993 ◽  
Vol 51 ◽  
pp. 128-129
Author(s):  
Béatrice Satiat-Jeunemaitre ◽  
Chris Hawes
Keyword(s):  
Plant Cell ◽  
Cell Walls ◽  
Cell Biology ◽  
Molecular Model ◽  
Three Dimensional ◽  
Secretory Activity ◽  
Wall Structure ◽  
Specimen Preparation ◽  
Molecular Architecture ◽  
Plant Cell Walls

The comprehension of the molecular architecture of plant cell walls is one of the best examples in cell biology which illustrates how developments in microscopy have extended the frontiers of a topic. Indeed from the first electron microscope observation of cell walls it has become apparent that our understanding of wall structure has advanced hand in hand with improvements in the technology of specimen preparation for electron microscopy. Cell walls are sub-cellular compartments outside the peripheral plasma membrane, the construction of which depends on a complex cellular biosynthetic and secretory activity (1). They are composed of interwoven polymers, synthesised independently, which together perform a number of varied functions. Biochemical studies have provided us with much data on the varied molecular composition of plant cell walls. However, the detailed intermolecular relationships and the three dimensional arrangement of the polymers in situ remains a mystery. The difficulty in establishing a general molecular model for plant cell walls is also complicated by the vast diversity in wall composition among plant species.

Wheat cell walls and constituent polysaccharides induce similar microbiota profiles upon in vitro fermentation despite different short chain fatty acid end-product levels.

2021 ◽  
Author(s):  
Shiyi Lu ◽  
Deirdre Mikkelsen ◽  
Hong Yao ◽  
Barbara Williams ◽  
Bernadine Flanagan ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Gut Microbiota ◽  
Plant Cell ◽  
Cell Walls ◽  
Short Chain Fatty Acid ◽  
Chain Fatty Acid ◽  
Plant Cell Walls ◽  
Human Gut ◽  
In Vitro Fermentation

Plant cell walls as well as their component polysaccharides in foods can be utilized to alter and maintain a beneficial human gut microbiota, but it is not known whether the...

scholarly journals Plant Cell Wall Hydration and Plant Physiology: An Exploration of the Consequences of Direct Effects of Water Deficit on the Plant Cell Wall

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1263
Author(s):  
David Stuart Thompson ◽  
Azharul Islam
Keyword(s):  
Cell Wall ◽  
Water Content ◽  
Bacterial Cellulose ◽  
Plant Cell ◽  
Cell Walls ◽  
Plant Cell Wall ◽  
Plant Cell Walls ◽  
Cell Wall Polysaccharides ◽  
Degree Of Hydration ◽  
Cellulose Composites

The extensibility of synthetic polymers is routinely modulated by the addition of lower molecular weight spacing molecules known as plasticizers, and there is some evidence that water may have similar effects on plant cell walls. Furthermore, it appears that changes in wall hydration could affect wall behavior to a degree that seems likely to have physiological consequences at water potentials that many plants would experience under field conditions. Osmotica large enough to be excluded from plant cell walls and bacterial cellulose composites with other cell wall polysaccharides were used to alter their water content and to demonstrate that the relationship between water potential and degree of hydration of these materials is affected by their composition. Additionally, it was found that expansins facilitate rehydration of bacterial cellulose and cellulose composites and cause swelling of plant cell wall fragments in suspension and that these responses are also affected by polysaccharide composition. Given these observations, it seems probable that plant environmental responses include measures to regulate cell wall water content or mitigate the consequences of changes in wall hydration and that it may be possible to exploit such mechanisms to improve crop resilience.

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