Different Environmental Stress for Enhanced Biofuel Production from Plant Biomass

2020 ◽  
pp. 21-34
Author(s):  
S. Joshi ◽  
M. Choudhary ◽  
N. Srivastava
Keyword(s):  
Environmental Stress ◽  
Plant Biomass ◽  
Biofuel Production

scholarly journals Plants: biofactories for a sustainable future?

2011 ◽  
Vol 369 (1942) ◽  
pp. 1826-1839 ◽  
Author(s):  
Thomas Jenkins ◽  
Aurélie Bovi ◽  
Robert Edwards
Keyword(s):  
Organic Carbon ◽  
Large Scale ◽  
Plant Biomass ◽  
Biofuel Production ◽  
Scale Production ◽  
Edible Plant ◽  
Oil Reserves ◽  
Optimal Processing ◽  
Large Scale Production ◽  
Food Applications

Depletion of oil reserves and the associated effects on climate change have prompted a re-examination of the use of plant biomass as a sustainable source of organic carbon for the large-scale production of chemicals and materials. While initial emphasis has been placed on biofuel production from edible plant sugars, the drive to reduce the competition between crop usage for food and non-food applications has prompted massive research efforts to access the less digestible saccharides in cell walls (lignocellulosics). This in turn has prompted an examination of the use of other plant-derived metabolites for the production of chemicals spanning the high-value speciality sectors through to platform intermediates required for bulk production. The associated science of biorefining, whereby all plant biomass can be used efficiently to derive such chemicals, is now rapidly developing around the world. However, it is clear that the heterogeneity and distribution of organic carbon between valuable products and waste streams are suboptimal. As an alternative, we now propose the use of synthetic biology approaches to ‘re-construct’ plant feedstocks for optimal processing of biomass for non-food applications. Promising themes identified include re-engineering polysaccharides, deriving artificial organelles, and the reprogramming of plant signalling and secondary metabolism.

scholarly journals Annual Removal of Aboveground Plant Biomass Alters Soil Microbial Responses to Warming

mBio ◽  
2016 ◽  
Vol 7 (5) ◽  
Author(s):  
Kai Xue ◽  
Mengting M. Yuan ◽  
Jianping Xie ◽  
Dejun Li ◽  
Yujia Qin ◽  
...  
Keyword(s):  
Nitrogen Fixation ◽  
Soil Carbon ◽  
Plant Biomass ◽  
Biofuel Production ◽  
Interactive Effects ◽  
Functional Genes ◽  
Soil Microbial ◽  
Recalcitrant Carbon ◽  
Microbial Responses

ABSTRACT Clipping (i.e., harvesting aboveground plant biomass) is common in agriculture and for bioenergy production. However, microbial responses to clipping in the context of climate warming are poorly understood. We investigated the interactive effects of grassland warming and clipping on soil properties and plant and microbial communities, in particular, on microbial functional genes. Clipping alone did not change the plant biomass production, but warming and clipping combined increased the C 4 peak biomass by 47% and belowground net primary production by 110%. Clipping alone and in combination with warming decreased the soil carbon input from litter by 81% and 75%, respectively. With less carbon input, the abundances of genes involved in degrading relatively recalcitrant carbon increased by 38% to 137% in response to either clipping or the combined treatment, which could weaken long-term soil carbon stability and trigger positive feedback with respect to warming. Clipping alone also increased the abundance of genes for nitrogen fixation, mineralization, and denitrification by 32% to 39%. Such potentially stimulated nitrogen fixation could help compensate for the 20% decline in soil ammonium levels caused by clipping alone and could contribute to unchanged plant biomass levels. Moreover, clipping tended to interact antagonistically with warming, especially with respect to effects on nitrogen cycling genes, demonstrating that single-factor studies cannot predict multifactorial changes. These results revealed that clipping alone or in combination with warming altered soil and plant properties as well as the abundance and structure of soil microbial functional genes. Aboveground biomass removal for biofuel production needs to be reconsidered, as the long-term soil carbon stability may be weakened. IMPORTANCE Global change involves simultaneous alterations, including those caused by climate warming and land management practices (e.g., clipping). Data on the interactive effects of warming and clipping on ecosystems remain elusive, particularly in microbial ecology. This study found that clipping alters microbial responses to warming and demonstrated the effects of antagonistic interactions between clipping and warming on microbial functional genes. Clipping alone or combined with warming enriched genes degrading relatively recalcitrant carbon, likely reflecting the decreased quantity of soil carbon input from litter, which could weaken long-term soil C stability and trigger positive warming feedback. These results have important implications in assessing and predicting the consequences of global climate change and indicate that the removal of aboveground biomass for biofuel production may need to be reconsidered.

scholarly journals Substrate-Specific Development of Thermophilic Bacterial Consortia by Using Chemically Pretreated Switchgrass

2014 ◽  
Vol 80 (23) ◽  
pp. 7423-7432 ◽  
Author(s):  
Stephanie A. Eichorst ◽  
Chijioke Joshua ◽  
Noppadon Sathitsuksanoh ◽  
Seema Singh ◽  
Blake A. Simmons ◽  
...  
Keyword(s):  
Microbial Communities ◽  
Plant Biomass ◽  
Biofuel Production ◽  
Rrna Gene ◽  
Gravimetric Analysis ◽  
Content Type ◽  
Biomass Deconstruction ◽  
Bacterial Consortia ◽  
Residual Biomass ◽  
Chemical Pretreatments

ABSTRACTMicrobial communities that deconstruct plant biomass have broad relevance in biofuel production and global carbon cycling. Biomass pretreatments reduce plant biomass recalcitrance for increased efficiency of enzymatic hydrolysis. We exploited these chemical pretreatments to study how thermophilic bacterial consortia adapt to deconstruct switchgrass (SG) biomass of various compositions. Microbial communities were adapted to untreated, ammonium fiber expansion (AFEX)-pretreated, and ionic-liquid (IL)-pretreated SG under aerobic, thermophilic conditions using green waste compost as the inoculum to study biomass deconstruction by microbial consortia. After microbial cultivation, gravimetric analysis of the residual biomass demonstrated that both AFEX and IL pretreatment enhanced the deconstruction of the SG biomass approximately 2-fold. Two-dimensional nuclear magnetic resonance (2D-NMR) experiments and acetyl bromide-reactive-lignin analysis indicated that polysaccharide hydrolysis was the dominant process occurring during microbial biomass deconstruction, and lignin remaining in the residual biomass was largely unmodified. Small-subunit (SSU) rRNA gene amplicon libraries revealed that although the dominant taxa across these chemical pretreatments were consistently represented by members of theFirmicutes, theBacteroidetes, andDeinococcus-Thermus, the abundance of selected operational taxonomic units (OTUs) varied, suggesting adaptations to the different substrates. Combining the observations of differences in the community structure and the chemical and physical structure of the biomass, we hypothesize specific roles for individual community members in biomass deconstruction.

scholarly journals Digesting the indigestible: Biosynthesis of the plant secondary wall

2011 ◽  
Vol 33 (2) ◽  
pp. 24-28
Author(s):  
Raymond Wightman ◽  
Simon Turner
Keyword(s):  
Cell Walls ◽  
Panicum Virgatum ◽  
Second Generation ◽  
Plant Biomass ◽  
Biofuel Production ◽  
Bioenergy Crops ◽  
Second Generation Biofuels ◽  
Biofuel Crops ◽  
Secondary Cell Walls ◽  
Micro Organisms

Biofuels have recently been the subject of intense debate with regard to‘food versus fuel’. Consequently, attention has focused upon so-called ‘second-generation’ biofuels that use alternatives to food-based feedstocks. In the best-developed forms of second-generation biofuels, sugars from starch digestion could be replaced with sugars released from the plant cell walls. This biomass could come from either agricultural residue, such as part of the maize culm, or from purpose grown biofuel crops, such as Miscanthus or Switchgrass (Panicum virgatum), that generate huge yields even when grown on marginal land with minimal agricultural inputs. For these and other potential bioenergy crops such as trees, the majority of the plant biomass is composed of woody secondary cell walls. If all cell wall sugars were readily accessible to fermenting micro-organisms, a 5 kg log could theoretically produce up to 2.5 litres of ethanol. The secondary cell walls are frequently the first line of defence against pests and pathogens, as well as providing structure and support for upward plant growth (Figure 1). Consequently, by their very nature, secondary cell walls are designed for strength and to resist degradation. The compact organization of the wall makes its digestion, a process known as saccharification, very difficult so biomass is currently too costly to be a viable feedstock. Knowledge of how the walls are constructed, however, would allow us to efficiently deconstruct them. This article gives an overview of secondary walls and potential modifications expected to be beneficial to improved biofuel production.

scholarly journals Clostridium thermocellum as a Promising Source of Genetic Material for Designer Cellulosomes: An Overview

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 996
Author(s):  
Dung Minh Ha-Tran ◽  
Trinh Thi My Nguyen ◽  
Chieh-Chen Huang
Keyword(s):  
Clostridium Thermocellum ◽  
Plant Cell Wall ◽  
Plant Biomass ◽  
Consolidated Bioprocessing ◽  
Genetic Material ◽  
Economic Feasibility ◽  
Biofuel Production ◽  
Cellulolytic Bacterium ◽  
Microbial Conversion ◽  
Promising Source

Plant biomass-based biofuels have gradually substituted for conventional energy sources thanks to their obvious advantages, such as renewability, huge quantity, wide availability, economic feasibility, and sustainability. However, to make use of the large amount of carbon sources stored in the plant cell wall, robust cellulolytic microorganisms are highly demanded to efficiently disintegrate the recalcitrant intertwined cellulose fibers to release fermentable sugars for microbial conversion. The Gram-positive, thermophilic, cellulolytic bacterium Clostridium thermocellum possesses a cellulolytic multienzyme complex termed the cellulosome, which has been widely considered to be nature’s finest cellulolytic machinery, fascinating scientists as an auspicious source of saccharolytic enzymes for biomass-based biofuel production. Owing to the supra-modular characteristics of the C. thermocellum cellulosome architecture, the cellulosomal components, including cohesin, dockerin, scaffoldin protein, and the plentiful cellulolytic and hemicellulolytic enzymes have been widely used for constructing artificial cellulosomes for basic studies and industrial applications. In addition, as the well-known microbial workhorses are naïve to biomass deconstruction, several research groups have sought to transform them from non-cellulolytic microbes into consolidated bioprocessing-enabling microbes. This review aims to update and discuss the current progress in these mentioned issues, point out their limitations, and suggest some future directions.

Biotechnological Potential of Bacterial Endoglucanase from Marine and Hypersaline Environments in Saccharification of Lignocellulosic Biomass Pre-Treated with Alkali or Ionic Liquid

2021 ◽  
Author(s):  
Abhijit Sar ◽  
Sudipto Biswas ◽  
Raju Biswas ◽  
Arijit Misra ◽  
Srikanta Pal ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Extracellular Enzymes ◽  
Plant Biomass ◽  
Halophilic Bacteria ◽  
Enzymatic Saccharification ◽  
Biofuel Production ◽  
Salt Adaptation ◽  
Rrna Gene ◽  
Generation Biofuel

Abstract In second-generation biofuel production, the recalcitrant plant biomass requires pretreatment prior to enzymatic hydrolysis. Pretreatment with alkali or ionic liquids (IL) such as 1-butyl 3-methyl immidazolium chloride ([Bmim][Cl]), are efficient but the residual salt in former, or IL in later process inhibits downstream enzymatic saccharification and thus require extensive washing. Recent studies have established IL tolerance by moderate halophilic bacteria being contributed by their general salt adaptation strategies. Objective of the present study is to examine whether the same holds true for their extracellular enzymes, and eventually select a few for future exploitation. In this direction, ten distinct endoglucanase positive (≥3 mm halo zone in congo-red cellulolytic assay) colonies were picked each from decomposed wood material of the hypersaline Sambhar Lake (SLW), in Rajasthan; and Bichitrapur (BPW) mangrove in Orissa. SLW and BPW samples had total salinities of 21.54% and 2.18%; and their isolates had optimum NaCl requirement of 10-15% and 1-5% respectively. The extracellular endoglucanase of SLW isolates were active in 5-25% NaCl but those from BPW remain active in only up to 5% NaCl. Interestingly, SLW endoglucanases also performed better in 10% and some even in 30% (v/v)[Bmim][Cl]. Endoglucanase secreted by two SLW isolates, identified by their 16S rRNA gene sequence as Salipaludibacillus sp. were effectively used for in situ enzymatic hydrolysis of both alkali and [Bmim][Cl] pretreated rice straw. However, endoglucanase from BPW isolate Salinicola sp. could hydrolyze seawater washed alkali-pretreated biomass thereby expanding their industrial applicability in coastal areas.

Cellulase Enzyme based Biodegradation of Cellulosic Materials: An Overview

2016 ◽  
Vol 5 (6) ◽  
pp. 271-282
Author(s):  
Soumya Chatterjee ◽  
Sonika Sharma ◽  
Rajesh Kumar Prasad ◽  
Sibnarayan Datta ◽  
Dharmendra Dubey ◽  
...  
Keyword(s):  
Plant Biomass ◽  
Raw Materials ◽  
Insect Pest ◽  
Biofuel Production ◽  
Anthropogenic Sources ◽  
Organic Polymer ◽  
Cellulase Enzymes ◽  
Technological Advances ◽  
Insect Gut ◽  
Main Component

Cellulose, a macromolecule of β -D- anhydroglucopyranose units linked by β (1,4)-glycosidic bonds, is the world’s most abundant organic polymer and is the main component of plant biomass that provides stability. Due to its sta-ble fibrous property, it has become one of the most important commercial raw materials for many industries. However, accumulation of waste cellulose due to natural and/or anthropogenic sources is a matter of concern in terms of environmental pollution. Wastes cellulosic substrates can be utilized as sources of energy through controlled hydrolysis using cellulases- a complex group of enzymes capable of degrading all types of cellulosic waste materials. A number of bacteria, fungi and insects are having the capability to degrade cellulose by production of cellulase enzymes. Further, the symbiotic insect-microbe relationships present in the insect gut microbiome for the production of cellulolytic system is of immense importance as this would lead to applications in different fields like biodegradation of cellulosic wastes, pollution reduction, biofuel production, insect/pest control etc. Cel-lulase gene can also be improved by genetic or protein engineering methods using recent technological advances. This review deals with the advances of cellulase enzymes and its utilization for different application.

Impact of ionic liquid pretreated plant biomass on Saccharomyces cerevisiae growth and biofuel production

2011 ◽  
Vol 13 (10) ◽  
pp. 2743 ◽  
Author(s):  
Mario Ouellet ◽  
Supratim Datta ◽  
Dean C. Dibble ◽  
Pramila R. Tamrakar ◽  
Peter I. Benke ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Ionic Liquid ◽  
Plant Biomass ◽  
Biofuel Production

scholarly journals Estimation of herbicide bioconcentration in sugarcane (Saccharum officinarum L.)

2015 ◽  
Vol 45 (4) ◽  
pp. 591-597 ◽  
Author(s):  
Antonio Luiz Cerdeira ◽  
Lourival Costa Paraíba ◽  
Sonia Claudia Nascimento de Queiroz ◽  
Marcus Barifouse Matallo ◽  
Daniel Andrade de siqueira Franco ◽  
...  
Keyword(s):  
Partition Coefficient ◽  
Plant Biomass ◽  
Saccharum Officinarum ◽  
Biofuel Production ◽  
Sugarcane Plant ◽  
Physiological Properties ◽  
Water Partition Coefficient ◽  
Total Plant Biomass ◽  
Total Plant ◽  
Herbicide Concentration

Sugarcane is an important crop for sugar and biofuel production in Brazil. Growers depend greatly on herbicides to produce it. This experiment used herbicide physical-chemical and sugarcane plant physiological properties to simulate herbicide uptake and estimate the bioconcentration factor (BCF). The (BCF) was calculated for the steady state chemical equilibrium between the plant herbicide concentration and soil solution. Plant-water partition coefficient (sugarcane bagasse-water partition coefficient), herbicide dilution rate, metabolism and dissipation in the soil-plant system, as well as total plant biomass factors were used. In addition, we added Tebuthiuron at rate of 5.0kg a.i. ha-1 to physically test the model. In conclusion, the model showed the following ranking of herbicide uptake: sulfentrazone > picloram >tebuthiuron > hexazinone > metribuzin > simazine > ametryn > diuron > clomazone > acetochlor. Furthermore, the highest BCF herbicides showed higher Groundwater Ubiquity Score (GUS) index indicating high leaching potential. We did not find tebuthiuron in plants after three months of herbicide application

Sign in / Sign up

Export Citation Format

Share Document