scholarly journals Properties of Thermobifida fusca peroxidase Tfu-1649 and its combined synergistic effects with xylanase on lignocellulose degradation

BioResources ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 942-953
Author(s):  
Wan-Yu Liao ◽  
Yu-Chun Huang ◽  
Wei-Lin Chen ◽  
Cheng-Yu Chen ◽  
Chao-Hsun Yang
Keyword(s):  
Reducing Sugars ◽  
Plant Biomass ◽  
Synergistic Effects ◽  
Culture Broth ◽  
Lignocellulose Degradation ◽  
Total Phenolic ◽  
Thermobifida Fusca ◽  
Zizania Latifolia ◽  
Thermophilic Actinomycetes ◽  
Biomass Decomposition

Lignocelluloses are comprised of cellulose, hemicellulose, and lignins, which constitute plant biomass. Since peroxidases can degrade lignins, the authors examined peroxidase Tfu-1649, which is secreted from the thermophilic actinomycetes, Thermobifida fusca BCRC 19214. After cultivating for 48 h, the culture broth accumulated 43.66 U/mL of peroxidase activity. The treatment of four types of lignocellulolytic byproducts, i.e., bagasse, corncob, pin sawdust, and Zizania latifolia Turcz husk, with Tfu-1649 alone increased the total phenolic compounds, with limited reducing sugars, but treatment with xylanase, Tfu-11, and peroxidase Tfu-1649 showed synergistic effects. Hence, the co-operative degradation of lignocelluloses by both peroxidase and xylanase could contribute to biomass decomposition and further applications in the agricultural and environmental industries.

scholarly journals Decomposition of Rice Chaff Using a Cocultivation System of Thermobifida fusca and Ureibacillus thermosphaericus

Proceedings ◽  
2021 ◽  
Vol 66 (1) ◽  
pp. 31
Author(s):  
Sachiko Nakamura ◽  
Norio Kurosawa
Keyword(s):  
Lignin Peroxidase ◽  
Culture Medium ◽  
Reducing Sugars ◽  
Thermophilic Bacteria ◽  
Thermobifida Fusca ◽  
Bacterial Strains ◽  
Basal Salt Medium ◽  
Moderately Thermophilic ◽  
Fuels And Chemicals ◽  
Ureibacillus Thermosphaericus

Lignocellulosic biomass comprises cellulose, hemicellulose, and lignin and is a potential source of fuels and chemicals. Although this complex biomass is persistent, it can be cooperatively decomposed by a microbial consortium in nature. In this study, a coculture of the moderately thermophilic bacteria Thermobifida fusca and Ureibacillus thermosphaericus was used for biodegradation of rice chaff. The bacterial strains were incubated in modified Brock’s basal salt medium (pH 8.0) supplemented with yeast extract and rice chaff at 50 °C for 7 days. The concentration of reducing sugars and the enzymatic activities of laccase, lignin peroxidase, cellulase, and xylanase in the supernatant of the culture medium were measured every day. The concentrations of reducing sugars in solo cultures of T. fusca and U. thermosphaericus and a mixed culture of the two strains after 7 days of incubation were 0.047, 0.040, and 0.195 mg/mL, respectively, indicating that the decomposition of rice chaff was enhanced in the coculture. Based on the results, it is thought that the lignin surrounding the cellulose was decomposed by laccase and lignin peroxidase secreted from U. thermosphaericus, resulting in cellulose and hemicellulose in the rice chaff being easily decomposed by enzymes from T. fusca.

scholarly journals Cross-Feeding of a Toxic Metabolite in a Synthetic Lignocellulose-Degrading Microbial Community

2021 ◽  
Vol 9 (2) ◽  
pp. 321
Author(s):  
Jessica A. Lee ◽  
Alyssa C. Baugh ◽  
Nicholas J. Shevalier ◽  
Brandi Strand ◽  
Sergey Stolyar ◽  
...  
Keyword(s):  
Resource Competition ◽  
Plant Biomass ◽  
Lignocellulose Degradation ◽  
Toxic Metabolite ◽  
Growth Requirements ◽  
Mutualistic Interaction ◽  
Metabolite Exchange ◽  
Future Work ◽  
Biomass Transformation ◽  
Complex Organic

The recalcitrance of complex organic polymers such as lignocellulose is one of the major obstacles to sustainable energy production from plant biomass, and the generation of toxic intermediates can negatively impact the efficiency of microbial lignocellulose degradation. Here, we describe the development of a model microbial consortium for studying lignocellulose degradation, with the specific goal of mitigating the production of the toxin formaldehyde during the breakdown of methoxylated aromatic compounds. Included are Pseudomonas putida, a lignin degrader; Cellulomonas fimi, a cellulose degrader; and sometimes Yarrowia lipolytica, an oleaginous yeast. Unique to our system is the inclusion of Methylorubrum extorquens, a methylotroph capable of using formaldehyde for growth. We developed a defined minimal “Model Lignocellulose” growth medium for reproducible coculture experiments. We demonstrated that the formaldehyde produced by P. putida growing on vanillic acid can exceed the minimum inhibitory concentration for C. fimi, and, furthermore, that the presence of M. extorquens lowers those concentrations. We also uncovered unexpected ecological dynamics, including resource competition, and interspecies differences in growth requirements and toxin sensitivities. Finally, we introduced the possibility for a mutualistic interaction between C. fimi and M. extorquens through metabolite exchange. This study lays the foundation to enable future work incorporating metabolomic analysis and modeling, genetic engineering, and laboratory evolution, on a model system that is appropriate both for fundamental eco-evolutionary studies and for the optimization of efficiency and yield in microbially-mediated biomass transformation.

scholarly journals The Effect of Field Heat Reduction Methods on Fresh and Processing Qualities of Red and Russet Potato Cultivars

2021 ◽  
Vol 6 (2) ◽  
pp. 345-355
Author(s):  
Sastry S. Jayanty ◽  
◽  
Esam Emragi ◽  
David G. Holm
Keyword(s):  
Weight Loss ◽  
Wound Healing ◽  
Reducing Sugars ◽  
Reduction Method ◽  
French Fries ◽  
Total Phenolic ◽  
French Fry ◽  
Russet Norkotah ◽  
Fry Color ◽  
Reduction Methods

The effect of three field heat reduction methods, including temperature lowering stepwise (TLS), temperature lowering gradually (TLG), and temperature lowering immediately (TLI), after harvesting on the quality of Russet Norkotah 3 and red skin numbered line CO 07102-1R potatoes were investigated. The tubers were analyzed at harvest (0 time), when they reached 3 °C, and after 6 months of storage at 3 °C for physiological weight loss, firmness, wound healing, total phenolics content, reducing sugars, and color of french fries. The results indicated that weight and firmness losses were lower under the TLS reduction method after 6 months of storage than TLG and TLI methods. The weight loss in TLS is 12%, TLG 14% and TLI 17% in CO 07102-1R whereas Russet Norkotah TLS is 4%, TLG 6%, and TLI 8% respectively. Wound healing was more effective using the TLS reduction method, especially in Russet Norkotah 3. French fry color was lighter at harvest (USDA grade 0), while there were no differences in the color of French fries prepared from tubers stored under the TLS and TLG methods (both had USDA grade 2). French fries were darker for tubers from the TLI method (USDA grade 4). The total phenolic content and reducing sugars were significantly increased in the TLI field heat reduction method. Keywords: Potato, Storage management, Wound healing, Weight loss, French fry

scholarly journals Soil-Derived Microbial Consortia Enriched with Different Plant Biomass Reveal Distinct Players Acting in Lignocellulose Degradation

2015 ◽  
Vol 71 (3) ◽  
pp. 616-627 ◽  
Author(s):  
Maria Julia de Lima Brossi ◽  
Diego Javier Jiménez ◽  
Larisa Cortes-Tolalpa ◽  
Jan Dirk van Elsas
Keyword(s):  
Plant Biomass ◽  
Microbial Consortia ◽  
Lignocellulose Degradation

scholarly journals Co-infection of Beet mosaic virus with Beet Yellowing Viruses Leads to Increased Symptom Expression on Sugar Beet

Plant Disease ◽  
2005 ◽  
Vol 89 (3) ◽  
pp. 325-331 ◽  
Author(s):  
William M. Wintermantel
Keyword(s):  
Sugar Beet ◽  
Mosaic Virus ◽  
Plant Biomass ◽  
Synergistic Effects ◽  
Blot Hybridization ◽  
Virus Concentration ◽  
Mixed Infections ◽  
Dot Blot ◽  
Plant Weight ◽  
Severe Stunting

Three distinct aphid-transmitted viruses associated with a yellowing disease on sugar beet were examined in single and mixed infections for the effects of virus interactions on plant weight, rate of symptom development, and virus concentration. Sugar beet lines exhibiting different degrees of susceptibility to the virus yellows complex were inoculated with either one, two, or all three viruses. Severe stunting, as measured by fresh plant biomass, was observed with mixed infections with Beet yellows virus (BYV) and Beet mosaic virus (BtMV), compared to single infections of these viruses. In addition, the overall rate of appearance of Beet western yellows virus (BWYV) symptoms increased during co-infection with BtMV. Synergistic effects on stunting severity, as measured by plant biomass, were more pronounced in susceptible beet lines, but similar patterns also were observed in lines exhibiting tolerance to virus yellows. Relative concentrations of viruses were compared among single and mixed infections using dot-blot hybridization with virus specific probes, and quantified by phosphorimage analysis. Titers of all three viruses increased as a result of co-infection compared with single infections.

scholarly journals Synergistic impacts of habitat loss and fragmentation on model ecosystems

2016 ◽  
Vol 283 (1839) ◽  
pp. 20161027 ◽  
Author(s):  
Lewis J. Bartlett ◽  
Tim Newbold ◽  
Drew W. Purves ◽  
Derek P. Tittensor ◽  
Michael B. J. Harfoot
Keyword(s):  
Land Use ◽  
Habitat Loss ◽  
Plant Biomass ◽  
Synergistic Effects ◽  
Ecosystem Model ◽  
Ecosystem Structure ◽  
Population Declines ◽  
Ecosystem Responses ◽  
Habitat Loss And Fragmentation ◽  
Biomass Loss

Habitat loss and fragmentation are major threats to biodiversity, yet separating their effects is challenging. We use a multi-trophic, trait-based, and spatially explicit general ecosystem model to examine the independent and synergistic effects of these processes on ecosystem structure. We manipulated habitat by removing plant biomass in varying spatial extents, intensities, and configurations. We found that emergent synergistic interactions of loss and fragmentation are major determinants of ecosystem response, including population declines and trophic pyramid shifts. Furthermore, trait-mediated interactions, such as a disproportionate sensitivity of large-sized organisms to fragmentation, produce significant effects in shaping responses. We also show that top-down regulation mitigates the effects of land use on plant biomass loss, suggesting that models lacking these interactions—including most carbon stock models—may not adequately capture land-use change impacts. Our results have important implications for understanding ecosystem responses to environmental change, and assessing the impacts of habitat fragmentation.

scholarly journals Divergence of compost extract and bio-organic manure effects on lucerne plant and soil

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3775 ◽  
Author(s):  
Haiyan Ren ◽  
Jian Hu ◽  
Yifei Hu ◽  
Gaowen Yang ◽  
Yingjun Zhang
Keyword(s):  
Plant Growth ◽  
Nutritive Value ◽  
Plant Biomass ◽  
Synergistic Effects ◽  
Soil Health ◽  
Treatment Plant ◽  
Organic Manure ◽  
Economic Returns ◽  
Rhizobium Inoculation ◽  
Compost Extract

AimApplication of organic materials into agricultural systems enhances plant growth and yields, and improves soil fertility and structure. This study aimed to examine the effects of “compost extract (CE)”, a soil conditioner, and bio-organic manure (BOM) on the growth of lucerne (Medicago sativa), and compare the efficiency between BOM (including numbers of microorganisms) and CE (including no added microorganisms).MethodA greenhouse experiment was conducted with four soil amendment treatments (control, BOM, CE and CEBOM), and was arranged in a completely randomized design with 10 replicates for each treatment. Plant biomass, nutritive value and rhizobia efficacy as well as soil characteristics were monitored.ResultCE rather than BOM application showed a positive effect on plant growth and soil properties when compared with the control. Lucerne nodulation responded equally to CE addition and rhizobium inoculation. CE alone and in combination with BOM significantly increased plant growth and soil microbial activities and improved soil structure. The synergistic effects of CE and BOM indicate that applying CE and BOM together could increase their efficiency, leading to higher economic returns and improved soil health. However, CE alone is more effective for legume growth since nodulation was suppressed by nitrogen input from BOM. CE had a higher efficiency than BOM for enriching soil indigenous microorganisms instead of adding microorganisms and favouring plant nodulation.

scholarly journals The termite fungal cultivar Termitomyces combines diverse enzymes and oxidative reactions for plant biomass conversion

2021 ◽  
Author(s):  
Felix Schalk ◽  
Cene Gostinčar ◽  
Nina B. Kreuzenbeck ◽  
Benjamin H. Conlon ◽  
Elisabeth Sommerwerk ◽  
...  
Keyword(s):  
Plant Biomass ◽  
Biomass Conversion ◽  
Degradation Mechanism ◽  
Oxidative Degradation ◽  
Ligninolytic Enzymes ◽  
Brown Rot ◽  
Dicarboxylic Acids ◽  
Lignocellulose Degradation ◽  
Redox Shuttle ◽  
Phenolic Polymer

AbstractMacrotermitine termites have domesticated fungi in the genus Termitomyces as their primary food source using pre-digested plant biomass. To access the full nutritional value of lignin-enriched plant biomass, the termite-fungus symbiosis requires the depolymerization of this complex phenolic polymer. While most previous work suggests that lignocellulose degradation is accomplished predominantly by the fungal cultivar, our current understanding of the underlying biomolecular mechanisms remains rudimentary. Here, we provide conclusive OMICs and activity-based evidence that Termitomyces partially depolymerizes lignocellulose through the combined actions of high-redox potential oxidizing enzymes (laccases, aryl-alcohol oxidases and a manganese peroxidase), the production of extracellular H2O2 and Fenton-based oxidative degradation, which is catalyzed by a newly described 2-methoxybenzoquinone/hydroquinone redox shuttle system and mediated by secreted chelating dicarboxylic acids. In combination, our approaches reveal a comprehensive depiction of how the efficient biomass degradation mechanism in this ancient insect agricultural symbiosis is accomplished through a combination of white- and brown-rot mechanisms.ImportanceFungus-growing termites have perfected the decomposition of recalcitrant plant biomass to access valuable nutrients by engaging in a tripartite symbiosis with complementary contributions from a fungal mutualist and a co-diversified gut microbiome. This complex symbiotic interplay makes them one of the most successful and important decomposers for carbon cycling in Old World ecosystems. To date, most research has focused on the enzymatic contributions of microbial partners to carbohydrate decomposition. Here we provide genomic, transcriptomic and enzymatic evidence that Termitomyces also employs redox mechanisms, including diverse ligninolytic enzymes and a Fenton-based hydroquinone-catalyzed lignin-degradation mechanism, to break down lignin-rich plant material. Insights into these efficient decomposition mechanisms open new sources of efficient ligninolytic agents applicable for energy generation from renewable sources.

scholarly journals Responses of Low-Cost Input Combinations on the Microbial Structure of the Maize Rhizosphere for Greenhouse Gas Mitigation and Plant Biomass Production

2021 ◽  
Vol 12 ◽  
Author(s):  
Caio Augusto Yoshiura ◽  
Andressa Monteiro Venturini ◽  
Lucas Palma Perez Braga ◽  
Aline Giovana da França ◽  
Maria do Carmo Catanho Pereira de Lyra ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Biomass Production ◽  
Plant Biomass ◽  
Control Plant ◽  
Ghg Emissions ◽  
Control Treatment ◽  
Lignocellulose Degradation ◽  
Microbial Composition ◽  
Maize Stover ◽  
Plant Biomass Production

The microbial composition of the rhizosphere and greenhouse gas (GHG) emissions under the most common input combinations in maize (Zea mays L.) cultivated in Brazil have not been characterized yet. In this study, we evaluated the influence of maize stover coverage (S), urea-topdressing fertilization (F), and the microbial inoculant Azospirillum brasilense (I) on soil GHG emissions and rhizosphere microbial communities during maize development. We conducted a greenhouse experiment and measured methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O) fluxes from soil cultivated with maize plants under factorial combinations of the inputs and a control treatment (F, I, S, FI, FS, IS, FIS, and control). Plant biomass was evaluated, and rhizosphere soil samples were collected at V5 and V15 stages and DNA was extracted. The abundance of functional genes (mcrA, pmoA, nifH, and nosZ) was determined by quantitative PCR (qPCR) and the structure of the microbial community was assessed through 16S rRNA amplicon sequencing. Our results corroborate with previous studies which used fewer input combinations and revealed different responses for the following three inputs: F increased N2O emissions around 1 week after application; I tended to reduce CH4 and CO2 emissions, acting as a plant growth stimulator through phytohormones; S showed an increment for CO2 emissions by increasing carbon-use efficiency. IS and FIS treatments presented significant gains in biomass that could be related to Actinobacteria (19.0%) and Bacilli (10.0%) in IS, and Bacilli (9.7%) in FIS, which are the microbial taxa commonly associated with lignocellulose degradation. Comparing all factors, the IS (inoculant + maize stover) treatment was considered the best option for plant biomass production and GHG mitigation since FIS provides small gains toward the management effort of F application.

scholarly journals Metabolic engineering of Saccharomyces cerevisiae for efficient conversions of glycerol to ethanol

2021 ◽  
Author(s):  
Sadat M. R. Khattab ◽  
Takashi Watanabe
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Production Rate ◽  
Nicotinamide Adenine Dinucleotide ◽  
Minimal Medium ◽  
Plant Biomass ◽  
Fine Tuning ◽  
Comprehensive Strategy ◽  
Oxidative Pathway ◽  
Efficient Fermentation ◽  
Biomass Decomposition

Glycerol is an eco-friendly solvent enhancing plant-biomass decomposition through the glycell process to bio-based chemicals. Nonetheless, the lack of efficient conversion of glycerol by natural Saccharomyces cerevisiae restrains many biorefineries-scenarios. Here, we outline a comprehensive strategy for generating efficient glycerol fermenting S. cerevisiae via rewriting the oxidation of cytosolic nicotinamide adenine dinucleotide by O2-dependent dynamic shuttle while abolishing glycerol phosphorylation and biosynthesis pathways. By following a vigorous glycerol oxidative pathway, our engineered strain demonstrated a breakthrough in conversion efficiency (CE), reaching up to 0.49g-ethanol/g-glycerol—98% of theoretical conversion—with production rate >1 gL−1h−1 on rich-medium. Interestingly, the glycerol consumption and its fermentation unrepressed during the mixing by glucose until the strain produced >86 g/L of bioethanol with 92.8% of CE. Moreover, fine-tuning of O2 boosted the production rate to >2 gL−1h−1with 82% of CE. Impressively, the strategy flipped the ancestral yeast even from non-growing on glycerol, on the minimal medium, to a fermenting strain with productivities 0.25-0.5 gL−1h−1 and 84-78% of CE, respectively. Our findings promote utlising glycerol efficiently in several eco-friendly biorefinery approaches.SummaryEfficient fermentation of glycerol in S. cerevisiae was established by comprehensive engineering of glycerol pathways and rewriting NADH pathway.

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