scholarly journals Novel Yeast Strains for the Efficient Saccharification and Fermentation of Starchy By-Products to Bioethanol

Energies ◽  
2019 ◽  
Vol 12 (4) ◽  
pp. 714 ◽  
Author(s):  
Nicoletta Gronchi ◽  
Lorenzo Favaro ◽  
Lorenzo Cagnin ◽  
Silvia Brojanigo ◽  
Valentino Pizzocchero ◽  
...  
Keyword(s):  
Process Integration ◽  
Consolidated Bioprocessing ◽  
Scale Up ◽  
Cost Savings ◽  
Value Added ◽  
Yeast Strains ◽  
Technological Advances ◽  
Set Up ◽  
Simultaneous Saccharification ◽  
Selection Of

The use of solid starchy waste streams to produce value-added products, such as fuel ethanol, is a priority for the global bio-based economy. Despite technological advances, bioethanol production from starch is still not economically competitive. Large cost-savings can be achieved through process integration (consolidated bioprocessing, CBP) and new amylolytic microbes that are able to directly convert starchy biomass into fuel in a single bioreactor. Firstly, CBP technology requires efficient fermenting yeast strains to be engineered for amylase(s) production. This study addressed the selection of superior yeast strains with high fermentative performances to be used as recipient for future CBP engineering of fungal amylases. Twenty-one newly isolated wild-type Saccharomyces cerevisiae strains were screened at 30 °C in a simultaneous saccharification and fermentation (SSF) set up using starchy substrates at high loading (20% w/v) and the commercial amylases cocktail STARGEN™ 002. The industrial yeast Ethanol Red™ was used as benchmark. A cluster of strains produced ethanol levels (up to 118 g/L) significantly higher than those of Ethanol Red™ (about 109 g/L). In particular, S. cerevisiae L20, selected for a scale-up process into a 1-L bioreactor, confirmed the outstanding performance over the industrial benchmark, producing nearly 101 g/L ethanol instead of 94 g/L. As a result, this strain can be a promising CBP host for heterologous expression of fungal amylases towards the design of novel and efficient starch-to-ethanol routes.

scholarly journals Engineered Pentafunctional Minicellulosome for Simultaneous Saccharification and Ethanol Fermentation in Saccharomyces cerevisiae

2014 ◽  
Vol 80 (21) ◽  
pp. 6677-6684 ◽  
Author(s):  
Youyun Liang ◽  
Tong Si ◽  
Ee Lui Ang ◽  
Huimin Zhao
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Carbon Source ◽  
Phosphoric Acid ◽  
Sole Carbon Source ◽  
Consolidated Bioprocessing ◽  
Content Type ◽  
Yeast Strains ◽  
Recombinant Yeast Strain ◽  
Polysaccharide Monooxygenases ◽  
Simultaneous Saccharification

ABSTRACTSeveral yeast strains have been engineered to express different cellulases to achieve simultaneous saccharification and fermentation of lignocellulosic materials. However, successes in these endeavors were modest, as demonstrated by the relatively low ethanol titers and the limited ability of the engineered yeast strains to grow using cellulosic materials as the sole carbon source. Recently, substantial enhancements to the breakdown of cellulosic substrates have been observed when lytic polysaccharide monooxygenases (LPMOs) were added to traditional cellulase cocktails. LPMOs are reported to cleave cellulose oxidatively in the presence of enzymatic electron donors such as cellobiose dehydrogenases. In this study, we coexpressed LPMOs and cellobiose dehydrogenases with cellobiohydrolases, endoglucanases, and β-glucosidases inSaccharomyces cerevisiae. These enzymes were secreted and docked onto surface-displayed miniscaffoldins through cohesin-dockerin interaction to generate pentafunctional minicellulosomes. The enzymes on the miniscaffoldins acted synergistically to boost the degradation of phosphoric acid swollen cellulose and increased the ethanol titers from our previously achieved levels of 1.8 to 2.7 g/liter. In addition, the newly developed recombinant yeast strain was also able to grow using phosphoric acid swollen cellulose as the sole carbon source. The results demonstrate the promise of the pentafunctional minicellulosomes for consolidated bioprocessing by yeast.

Platelet Anti-Aggregating Activity and Tolerance of Clopidogrel in Atherosclerotic Patients

1996 ◽  
Vol 76 (06) ◽  
pp. 0939-0943 ◽  
Author(s):  
B Boneu ◽  
G Destelle ◽  
Keyword(s):  
Platelet Aggregation ◽  
Large Scale ◽  
Bleeding Time ◽  
Antithrombotic Activity ◽  
Ambulatory Patients ◽  
Patients At Risk ◽  
Set Up ◽  
Ischemic Events ◽  
Large Scale Clinical Trial ◽  
Selection Of

SummaryThe anti-aggregating activity of five rising doses of clopidogrel has been compared to that of ticlopidine in atherosclerotic patients. The aim of this study was to determine the dose of clopidogrel which should be tested in a large scale clinical trial of secondary prevention of ischemic events in patients suffering from vascular manifestations of atherosclerosis [CAPRIE (Clopidogrel vs Aspirin in Patients at Risk of Ischemic Events) trial]. A multicenter study involving 9 haematological laboratories and 29 clinical centers was set up. One hundred and fifty ambulatory patients were randomized into one of the seven following groups: clopidogrel at doses of 10, 25, 50,75 or 100 mg OD, ticlopidine 250 mg BID or placebo. ADP and collagen-induced platelet aggregation tests were performed before starting treatment and after 7 and 28 days. Bleeding time was performed on days 0 and 28. Patients were seen on days 0, 7 and 28 to check the clinical and biological tolerability of the treatment. Clopidogrel exerted a dose-related inhibition of ADP-induced platelet aggregation and bleeding time prolongation. In the presence of ADP (5 \lM) this inhibition ranged between 29% and 44% in comparison to pretreatment values. The bleeding times were prolonged by 1.5 to 1.7 times. These effects were non significantly different from those produced by ticlopidine. The clinical tolerability was good or fair in 97.5% of the patients. No haematological adverse events were recorded. These results allowed the selection of 75 mg once a day to evaluate and compare the antithrombotic activity of clopidogrel to that of aspirin in the CAPRIE trial.

STUDY OF INACCURACY IN THE OPERATION OF THE MAIN CONTROLLER OF STB MACHINE

2019 ◽  
Keyword(s):  
Normal Distribution ◽  
Stable Process ◽  
Random Errors ◽  
Actual Length ◽  
Experimental Data Processing ◽  
Set Up ◽  
Main Regulator ◽  
Transmission Gear ◽  
Selection Of

At production of fabrics, including fabrics for agricultural purpose, an important role is played by the cor-rect adjustment of operation of machine main regulator. The quality of setup of machine main controller is determined by the proper selection of rotation angle of warp beam weaving per one filling thread. In the pro-cess of using the regulator as a result of mistakes in adjustment, wear of transmission gear and backlashes in connections of details there are random changes in threads length. The purpose of the article is the research of property of random errors of basis giving by STB machine regulator. Mistakes can be both negative, and positive. In case of emergence only negative or only positive mistakes operation of the machine becomes im-possible as there will be a consecutive accumulation of mistakes. As a result of experimental data processing for stable process of weaving and the invariable diameter of basis threads winding of threads it is revealed that the random error of giving is set up as linear function of the accidental length having normal distribution. Measurements of accidental deviations in giving of a basis by the main regulator allowed to construct a curve of normal distribution of its actual length for one pass of weft thread. The presented curve of distribution of random errors in giving of a basis is the displaced curve of normal distribution of the accidental sizes. Also we define the density of probability of normal distribution of basis giving errors connected with a margin er-ror operation of the main regulator knowing of which allows to plan ways of their decrease that is important for improvement of quality of the produced fabrics.

scholarly journals Effects and Economic Sustainability of Biochar Application on Corn Production in a Mediterranean Climate

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3313
Author(s):  
Juan Luis Aguirre ◽  
María Teresa Martín ◽  
Sergio González ◽  
Manuel Peinado
Keyword(s):  
Organic Carbon ◽  
Mediterranean Climate ◽  
Cost Savings ◽  
Value Added ◽  
Field Trials ◽  
Economic Sustainability ◽  
Corn Production ◽  
Enhanced Production ◽  
Wet Weight ◽  
The Mediterranean

The effects of two types of biochar on corn production in the Mediterranean climate during the growing season were analyzed. The two types of biochar were obtained from pyrolysis of Pinus pinaster. B1 was fully pyrolyzed with 55.90% organic carbon, and B2 was medium pyrolyzed with 23.50% organic carbon. B1 and B2 were supplemented in the soil of 20 plots (1 m2) at a dose of 4 kg/m2. C1 and C2 (10 plots each) served as control plots. The plots were automatically irrigated and fertilizer was not applied. The B1-supplemented plots exhibited a significant 84.58% increase in dry corn production per square meter and a 93.16% increase in corn wet weight (p << 0.001). Corn production was no different between B2-supplemented, C1, and C2 plots (p > 0.01). The weight of cobs from B1-supplemented plots was 62.3%, which was significantly higher than that of cobs from C1 and C2 plots (p < 0.01). The grain weight increased significantly by 23% in B1-supplemented plots (p < 0.01) and there were no differences between B2-supplemented, C1, and C2 plots. At the end of the treatment, the soil of the B1-supplemented plots exhibited increased levels of sulfate, nitrate, magnesium, conductivity, and saturation percentage. Based on these results, the economic sustainability of this application in agriculture was studied at a standard price of €190 per ton of biochar. Amortization of this investment can be achieved in 5.52 years according to this cost. Considering the fertilizer cost savings of 50% and the water cost savings of 25%, the amortization can be achieved in 4.15 years. If the price of biochar could be reduced through the CO2 emission market at €30 per ton of non-emitted CO2, the amortization can be achieved in 2.80 years. Biochar markedly improves corn production in the Mediterranean climate. However, the amortization time must be further reduced, and enhanced production must be guaranteed over the years with long term field trials so that the product is marketable or other high value-added crops must be identified.

scholarly journals Single-step ethanol production from raw cassava starch using a combination of raw starch hydrolysis and fermentation, scale-up from 5-L laboratory and 200-L pilot plant to 3000-L industrial fermenters

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Morakot Krajang ◽  
Kwanruthai Malairuang ◽  
Jatuporn Sukna ◽  
Krongchan Rattanapradit ◽  
Saethawat Chamsart
Keyword(s):  
Ethanol Production ◽  
Ethanol Concentration ◽  
Consolidated Bioprocessing ◽  
Scale Up ◽  
Cassava Starch ◽  
Single Step ◽  
Starch Hydrolysis ◽  
Yield Coefficient ◽  
Raw Starch ◽  
Raw Starch Hydrolysis

Abstract Background A single-step ethanol production is the combination of raw cassava starch hydrolysis and fermentation. For the development of raw starch consolidated bioprocessing technologies, this research was to investigate the optimum conditions and technical procedures for the production of ethanol from raw cassava starch in a single step. It successfully resulted in high yields and productivities of all the experiments from the laboratory, the pilot, through the industrial scales. Yields of ethanol concentration are comparable with those in the commercial industries that use molasses and hydrolyzed starch as the raw materials. Results Before single-step ethanol production, studies of raw cassava starch hydrolysis by a granular starch hydrolyzing enzyme, StargenTM002, were carefully conducted. It successfully converted 80.19% (w/v) of raw cassava starch to glucose at a concentration of 176.41 g/L with a productivity at 2.45 g/L/h when it was pretreated at 60 °C for 1 h with 0.10% (v/w dry starch basis) of Distillase ASP before hydrolysis. The single-step ethanol production at 34 °C in a 5-L fermenter showed that Saccharomyces cerevisiae (Fali, active dry yeast) produced the maximum ethanol concentration, pmax at 81.86 g/L (10.37% v/v) with a yield coefficient, Yp/s of 0.43 g/g, a productivity or production rate, rp at 1.14 g/L/h and an efficiency, Ef of 75.29%. Scale-up experiments of the single-step ethanol production using this method, from the 5-L fermenter to the 200-L fermenter and further to the 3000-L industrial fermenter were successfully achieved with essentially good results. The values of pmax,Yp/s, rp, and Ef of the 200-L scale were at 80.85 g/L (10.25% v/v), 0.42 g/g, 1.12 g/L/h and 74.40%, respectively, and those of the 3000-L scale were at 70.74 g/L (8.97% v/v), 0.38 g/g, 0.98 g/L/h and 67.56%, respectively. Because of using raw starch, major by-products, i.e., glycerol, lactic acid, and acetic acid of all three scales were very low, in ranges of 0.940–1.140, 0.046–0.052, 0.000–0.059 (% w/v), respectively, where are less than those values in the industries. Conclusion The single-step ethanol production using the combination of raw cassava starch hydrolysis and fermentation of three fermentation scales in this study is practicable and feasible for the scale-up of industrial production of ethanol from raw starch.

scholarly journals Consolidated bioprocessing of lignocellulose for production of glucaric acid by an artificial microbial consortium

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Chaofeng Li ◽  
Xiaofeng Lin ◽  
Xing Ling ◽  
Shuo Li ◽  
Hao Fang
Keyword(s):  
Acid Production ◽  
Microbial Consortium ◽  
Consolidated Bioprocessing ◽  
High Titer ◽  
Value Added ◽  
Superior Performance ◽  
Glucaric Acid ◽  
Practical Applications ◽  
Work Distribution ◽  
Rut C30

Abstract Background The biomanufacturing of d-glucaric acid has attracted increasing interest because it is one of the top value-added chemicals produced from biomass. Saccharomyces cerevisiae is regarded as an excellent host for d-glucaric acid production. Results The opi1 gene was knocked out because of its negative regulation on myo-inositol synthesis, which is the limiting step of d-glucaric acid production by S. cerevisiae. We then constructed the biosynthesis pathway of d-glucaric acid in S. cerevisiae INVSc1 opi1Δ and obtained two engineered strains, LGA-1 and LGA-C, producing record-breaking titers of d-glucaric acid: 9.53 ± 0.46 g/L and 11.21 ± 0.63 g/L d-glucaric acid from 30 g/L glucose and 10.8 g/L myo-inositol in fed-batch fermentation mode, respectively. However, LGA-1 was preferable because of its genetic stability and its superior performance in practical applications. There have been no reports on d-glucaric acid production from lignocellulose. Therefore, the biorefinery processes, including separated hydrolysis and fermentation (SHF), simultaneous saccharification and fermentation (SSF) and consolidated bioprocessing (CBP) were investigated and compared. CBP using an artificial microbial consortium composed of Trichoderma reesei (T. reesei) Rut-C30 and S. cerevisiae LGA-1 was found to have relatively high d-glucaric acid titers and yields after 7 d of fermentation, 0.54 ± 0.12 g/L d-glucaric acid from 15 g/L Avicel and 0.45 ± 0.06 g/L d-glucaric acid from 15 g/L steam-exploded corn stover (SECS), respectively. In an attempt to design the microbial consortium for more efficient CBP, the team consisting of T. reesei Rut-C30 and S. cerevisiae LGA-1 was found to be the best, with excellent work distribution and collaboration. Conclusions Two engineered S. cerevisiae strains, LGA-1 and LGA-C, with high titers of d-glucaric acid were obtained. This indicated that S. cerevisiae INVSc1 is an excellent host for d-glucaric acid production. Lignocellulose is a preferable substrate over myo-inositol. SHF, SSF, and CBP were studied, and CBP using an artificial microbial consortium of T. reesei Rut-C30 and S. cerevisiae LGA-1 was found to be promising because of its relatively high titer and yield. T. reesei Rut-C30 and S. cerevisiae LGA-1were proven to be the best teammates for CBP. Further work should be done to improve the efficiency of this microbial consortium for d-glucaric acid production from lignocellulose.

scholarly journals Status Update on Bioelectrochemical Systems: Prospects for Carbon Electrode Design and Scale-Up

Catalysts ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 278
Author(s):  
Katharina Herkendell
Keyword(s):  
Gradual Increase ◽  
Scale Up ◽  
Value Added ◽  
Biofuel Cells ◽  
Carbon Electrode ◽  
Electrode Design ◽  
Bioelectrochemical Systems ◽  
Electrode Assemblies ◽  
The Stability ◽  
Scientific Attention

Bioelectrochemical systems (BES) employ enzymes, subcellular structures or whole electroactive microorganisms as biocatalysts for energy conversion purposes, such as the electrosynthesis of value-added chemicals and power generation in biofuel cells. From a bioelectrode engineering viewpoint, customizable nanostructured carbonaceous matrices have recently received considerable scientific attention as promising electrode supports due to their unique properties attractive to bioelectronics devices. This review demonstrates the latest advances in the application of nano- and micro-structured carbon electrode assemblies in BES. Specifically, in view of the gradual increase in the commercial applicability of these systems, we aim to address the stability and scalability of different BES designs and to highlight their potential roles in a circular bioeconomy.

Aligning the flow cytometric evaluation with the diagnostic need: an evidence-based approach

2017 ◽  
Vol 70 (9) ◽  
pp. 740-744 ◽  
Author(s):  
Dawn Williams-Voorbeijtel ◽  
Francisco Sanchez ◽  
Christine G Roth
Keyword(s):  
Clinical Care ◽  
Cost Savings ◽  
Value Added ◽  
Cost Effective ◽  
Just In Time ◽  
Evidence Based ◽  
Flow Cytometric ◽  
A Value ◽  
Screening Approach ◽  
Minimum Requirements

AimsElimination of non-value added testing without compromising high-quality clinical care is an important mandate for laboratories in a value-based reimbursement system. The goal of this study was to determine the optimal combination of flow cytometric markers for a screening approach that balances efficiency and accuracy.MethodsAn audit over 9 months of flow cytometric testing was performed, including rereview of all dot plots from positive cases.ResultsOf the 807 cases in which leukaemia/lymphoma testing was performed, 23 were non-diagnostic and 189 represented bronchoalveolar lavage specimens. Of the remaining 595 cases, 137 (23%) were positive for an abnormal haematolymphoid population. Review of the positive cases identified minimum requirements for a screening tube as well as analysis strategies to overcome the diagnostic pitfalls noted. It is estimated that 38% fewer antibodies would be used in a screening approach, representing an opportunity for significant cost savings.ConclusionsWe provide a framework for developing an evidence-based screening combination for cost-effective characterisation of haematolymphoid malignancies, promoting adoption of ‘just-in-time’ testing systems that tailor the evaluation to the diagnostic need.

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