scholarly journals High Productivity Ethanol Fermentation of Glucose & Xylose Using Membrane Assisted Continuous Cell Recycle

2021 ◽  
pp. 8-19
Author(s):  
Gautam Degweker ◽  
Arvind Lali
Keyword(s):  
Ethanol Fermentation ◽  
Ethanol Yield ◽  
Continuous Fermentation ◽  
Cost Effective ◽  
High Yield ◽  
High Cell ◽  
Cell Recycle ◽  
High Productivity ◽  
Ethanol Yields ◽  
Cell Densities

Rapid and high yield conversion of xylose to ethanol remains a signi cant bottleneck in the cost-effective production of ethanol using mixed sugars derived from lignocellulosic biomass (LBM). The present study attempts to circumvent this by separate continuous fermentation of glucose and xylose using high cell densities of a Saccharomyces cerevisiae mutant (ICT-1) and a Scheffersomyces stipitis mutant (M1CD), respectively with the help of external micro ltration membrane assisted cell recycle. Different cell densities and aeration rates for xylose fermentation were studied for optimizing continuous fermentation. Consistent high ethanol yields and productivities of 0.46 g/g and 5.19 g/L/h with glucose; and 0.38 g/g and 1.62 g/L/h with xylose; were achieved in simple media. This provided an average ethanol yield of 0.44 g/g on combined sugars, and average productivity of 3.4 g/L/h which is higher than typical molasses-based batch ethanol fermentation. The study thus highlights the potential of high cell density recycle strategy as an effective approach for separate ethanol fermentation of LBM derived sugars.

scholarly journals Photosynthetic activity of parsnip varieties in the conditions of the Right-bank Forest-steppe of Ukraine

2020 ◽  
Vol 11 (4) ◽  
pp. 87-93
Author(s):  
O. O. Komar ◽  
◽  
O. V. Shemetun ◽  
V. O. Komar ◽  
◽  
...  
Keyword(s):  
Cost Effective ◽  
Climatic Conditions ◽  
High Yield ◽  
Forest Steppe ◽  
Plant Resources ◽  
High Productivity ◽  
Net Productivity ◽  
Photosynthetic Productivity ◽  
High Area ◽  
The Right

Due to the intensification of production of parsnip, the question arises to clarify the elements of cultivation technology that should ensure its high productivity. The use of varietal plant resources is one of the most important parts of agriculture - the basis of economic and social development of the state. The most efficient and cost-effective is the widespread introduction of new varieties and hybrids with a genetically determined level of adaptation to the conditions of soil and climatic zones of their cultivation. The indicator of the dynamics of the formation of photosynthetic productivity is the basis of the yield of each crop. The purpose of the research was to study the dynamics of leaf surface formation in varieties of parsnip in the conditions of the Right-Bank Forest-Steppe of Ukraine. The studied cultivars of parsnip sowing formed a high area of active assimilation surface, the dynamics of which depends on the stage of organogenesis, soil and climatic conditions of the year and varietal characteristics. With the highest average for the growing season leaf area (49.0-49.6 thousand m2 on ha), photosynthetic potential (1.79-1.83 million m2 per day on ha) and net productivity of photosynthesis - 5.56 g on m2 per day) were characterized by varieties Stymul and Pulse in terms of other varieties. It is established that in order to obtain stably high yield (44.4-45.4 t on ha) and marketability of root crops (85-93%) in the conditions of the Right-Bank Forest-Steppe of Ukraine it is necessary to sow highly productive varieties of parsnip sowing Stymul and Pulse.

Novel ethanol fermentations from sugar cane and straw

1987 ◽  
Vol 321 (1561) ◽  
pp. 555-568 ◽  
Keyword(s):  
High Temperature ◽  
Sugar Cane ◽  
Energy Input ◽  
Bacillus Stearothermophilus ◽  
High Yield ◽  
High Productivity ◽  
Capital Costs ◽  
Bulk Chemicals ◽  
Ethanol Yields ◽  
Hydrolysis Of

Most agree that it is ultimately desirable to produce bulk chemicals such as ethanol from renewable resources; the questions focus on ‘where’, ‘when’ and ‘how’. For developing counties with abundant biomass, growing needs for bulk chemicals and energy, and balance of exchange problems, the time is now. Sugar cane is an obvious feedstock but the economics depend on whole-crop utilization and capital and energy input. The latter is currently met by burning the cane straw (bagasse), but hydrolysis of this and fermentation and the resulting sugars would increase ethanol yields. A high-temperature fermentation would reduce energy input and capital costs. A mutant strain of Bacillus stearothermophilus (LLD-15) can make ethanol from sucrose at 70 °C in yields and at rates equivalent to yeasts at 30 °C. Aerobically, the wild type grows rapidly on many sugars, and equally rapidly anaerobically producing mainly L-lactate and traces of acetate, formate and ethanol via pyruvate-formate lyase. In the mutant, the latter anaerobic pathway normally predominates. But under certain stresses pyruvate flux can be diverted exclusively via pyruvate dehydrogenase, resulting in quantitative conversion of sucrose to ethanol and CO 2 without growth. Hence the mutant offers potential for novel fermentation processes at high temperature, with high yield, high productivity and broad substrate range.

scholarly journals PHA Productivity and Yield ofRalstonia eutrophaWhen Intermittently or Continuously Fed a Mixture of Short Chain Fatty Acids

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Panchali Chakraborty ◽  
Kasiviswanathan Muthukumarappan ◽  
William R. Gibbons
Keyword(s):  
Fermentation Process ◽  
Cost Effective ◽  
Short Chain Fatty Acids ◽  
Feeding Strategies ◽  
Corn Ethanol ◽  
High Cell ◽  
Pha Production ◽  
Condensed Corn Solubles ◽  
Cell Densities ◽  
Dual Substrate

The research described in this present study was part of a larger effort focused on developing a dual substrate, dual fermentation process to produce Polyhydroxyalkanoate (PHA). The focus of this study was developing and optimizing a strategy for feeding a mixture of SCFAs (simulated ARF) and maximizing PHA production in a cost-effective way. Three different feeding strategies were examined in this study. The substrate evaluated in this study for the growth phase ofR. eutrophawas condensed corn solubles, a low-value byproduct of the dry-mill, corn ethanol industry. The culture was grown to high cell densities in nitrogen-supplemented condensed corn solubles media in 5 L bioreactors. The overall growth rate ofR. eutrophawas 0.2 h−1. The 20 mL ARF feeding every 3 h from 48 to 109 h strategy gave the best results in terms of PHA production. PHA productivity (0.0697 g L−1 h−1), PHA concentration (8.37 g L−1), and PHA content (39.52%) were the highest when ARF was fed every 3 h for 61 h. This study proved that condensed corn solubles can be potentially used as a growth medium to boost PHA production byR. eutrophathus reducing the overall cost of biopolymer production.

Multi-stage high cell continuous fermentation for high productivity and titer

2010 ◽  
Vol 34 (4) ◽  
pp. 419-431 ◽  
Author(s):  
Ho Nam Chang ◽  
Nag-Jong Kim ◽  
Jongwon Kang ◽  
Chang Moon Jeong ◽  
Jin-dal-rae Choi ◽  
...  
Keyword(s):  
Continuous Fermentation ◽  
High Cell ◽  
High Productivity ◽  
Multi Stage

High cell density ethanol fermentation in an upflow packed-bed cell recycle bioreactor

2008 ◽  
Vol 13 (2) ◽  
pp. 123-135 ◽  
Author(s):  
Ho Nam Chang ◽  
Byoung Jin Kim ◽  
Jong Won Kang ◽  
Chang Moon Jeong ◽  
Nag-Jong Kim ◽  
...  
Keyword(s):  
Cell Density ◽  
Ethanol Fermentation ◽  
High Cell Density ◽  
Packed Bed ◽  
High Cell ◽  
Cell Recycle

Quality Improvement of the DNA extracted by boiling method in Gram negative bacteria

2017 ◽  
Vol 6 (04) ◽  
pp. 5347 ◽  
Author(s):  
Omar B. Ahmed* ◽  
Anas S. Dablool
Keyword(s):  
Dna Extraction ◽  
Control Method ◽  
Extraction Procedure ◽  
Cost Effective ◽  
High Yield ◽  
Gram Negative Bacteria ◽  
Bacterial Dna ◽  
Gram Negative ◽  
E Coli

Several methods of Deoxyribonucleic acid (DNA) extraction have been applied to extract bacterial DNA. The amount and the quality of the DNA obtained for each one of those methods are variable. The study aimed to evaluate bacterial DNA extraction using conventional boiling method followed by alcohol precipitation. DNA extraction from Gram negative bacilli was extracted and precipitated using boiling method with further precipitation by ethanol. The extraction procedure performed using the boiling method resulted in high DNA yields for both E. coli and K. pneumoniae bacteria in (199.7 and 285.7μg/ml, respectively) which was close to control method (229.3 and 440.3μg/ml). It was concluded that after alcohol precipitation boiling procedure was easy, cost-effective, and applicable for high-yield quality of DNA in Gram-negative bacteria.

scholarly journals Cost Effectiveness of Transbronchial Needle Aspiration

1999 ◽  
Vol 6 (4) ◽  
pp. 332-335 ◽  
Author(s):  
Jennifer A Crocket ◽  
Eric YL Wong ◽  
Dale C Lien ◽  
Khanh Gia Nguyen ◽  
Michelle R Chaput ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Cost Effective ◽  
Diagnostic Procedures ◽  
Needle Aspiration ◽  
Benign Disease ◽  
University Hospital ◽  
High Yield ◽  
Transbronchial Needle Aspiration ◽  
Computed Tomographic ◽  
The Cost

OBJECTIVE: To evaluate the yield and cost effectiveness of transbronchial needle aspiration (TBNA) in the assessment of mediastinal and/or hilar lymphadenopathy.DESIGN: Retrospective study.SETTING: A university hospital.POPULATION STUDIED: Ninety-six patients referred for bronchoscopy with computed tomographic evidence of significant mediastinal or hilar adenopathy.RESULTS: Ninety-nine patient records were reviewed. Three patients had two separate bronchoscopy procedures. TBNA was positive in 42 patients (44%) and negative in 54 patients. Of the 42 patients with a positive aspirate, 40 had malignant cytology and two had cells consistent with benign disease. The positive TBNA result altered management in 22 of 40 patients with malignant disease and one of two patients with benign disease, thereby avoiding further diagnostic procedures. The cost of these subsequent procedures was estimated at $27,335. No complications related to TBNA were documented.CONCLUSIONS: TBNA is a high-yield, safe and cost effective procedure for the diagnosis and staging of bronchogenic cancer.

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