scholarly journals Bioprocesses with Reduced Ecological Footprint by Marine Debaryomyces hansenii Strain for Potential Applications in Circular Economy

2021 ◽  
Vol 7 (12) ◽  
pp. 1028
Author(s):  
Silvia Donzella ◽  
Claudia Capusoni ◽  
Luisa Pellegrino ◽  
Concetta Compagno
Keyword(s):  
Ecological Footprint ◽  
Debaryomyces Hansenii ◽  
High Growth ◽  
High Growth Rate ◽  
Food Industries ◽  
Starting Point ◽  
Wide Range ◽  
Potential Applications ◽  
A Cell ◽  
Marine Strain

The possibility to perform bioprocesses with reduced ecological footprint to produce natural compounds and catalyzers of industrial interest is pushing the research for salt tolerant microorganisms able to grow on seawater-based media and able to use a wide range of nutrients coming from waste. In this study we focused our attention on a Debaryomyces hansenii marine strain (Mo40). We optimized cultivation in a bioreactor at low pH on seawater-based media containing a mixture of sugars (glucose and xylose) and urea. Under these conditions the strain exhibited high growth rate and biomass yield. In addition, we characterized potential applications of this yeast biomass in food/feed industry. We show that Mo40 can produce a biomass containing 45% proteins and 20% lipids. This strain is also able to degrade phytic acid by a cell-bound phytase activity. These features represent an appealing starting point for obtaining D. hansenii biomass in a cheap and environmentally friendly way, and for potential use as an additive or to replace unsustainable ingredients in the feed or food industries, as this species is included in the QPS EFSA list (Quality Presumption as Safe—European Food Safety Authority).

scholarly journals Sporulation in solventogenic and acetogenic clostridia

2021 ◽  
Author(s):  
Mamou Diallo ◽  
Servé W. M. Kengen ◽  
Ana M. López-Contreras
Keyword(s):  
Current Knowledge ◽  
Carbon Sources ◽  
Cost Effective ◽  
Biotechnological Production ◽  
Key Points ◽  
Wide Range ◽  
Potential Applications ◽  
A Cell ◽  
Sporulation Initiation ◽  
Solventogenic Clostridia

AbstractThe Clostridium genus harbors compelling organisms for biotechnological production processes; while acetogenic clostridia can fix C1-compounds to produce acetate and ethanol, solventogenic clostridia can utilize a wide range of carbon sources to produce commercially valuable carboxylic acids, alcohols, and ketones by fermentation. Despite their potential, the conversion by these bacteria of carbohydrates or C1 compounds to alcohols is not cost-effective enough to result in economically viable processes. Engineering solventogenic clostridia by impairing sporulation is one of the investigated approaches to improve solvent productivity. Sporulation is a cell differentiation process triggered in bacteria in response to exposure to environmental stressors. The generated spores are metabolically inactive but resistant to harsh conditions (UV, chemicals, heat, oxygen). In Firmicutes, sporulation has been mainly studied in bacilli and pathogenic clostridia, and our knowledge of sporulation in solvent-producing or acetogenic clostridia is limited. Still, sporulation is an integral part of the cellular physiology of clostridia; thus, understanding the regulation of sporulation and its connection to solvent production may give clues to improve the performance of solventogenic clostridia. This review aims to provide an overview of the triggers, characteristics, and regulatory mechanism of sporulation in solventogenic clostridia. Those are further compared to the current knowledge on sporulation in the industrially relevant acetogenic clostridia. Finally, the potential applications of spores for process improvement are discussed.Key Points• The regulatory network governing sporulation initiation varies in solventogenic clostridia.• Media composition and cell density are the main triggers of sporulation.• Spores can be used to improve the fermentation process.

scholarly journals Model experiment for cleaning oil-contaminated soils

2020 ◽  
Vol 62 (5) ◽  
pp. 130-141
Author(s):  
Alibek A. Kaziev ◽  
◽  
Amantay Sh. Akzhigitov ◽  
Sofia Z. Sagyndykova ◽  
Azamat N. Nurlybekov ◽  
...  
Keyword(s):  
Contaminated Soils ◽  
Immobilized Cells ◽  
Research Work ◽  
Rhodococcus Erythropolis ◽  
Practical Interest ◽  
High Growth ◽  
High Growth Rate ◽  
Rhodococcus Ruber ◽  
Oil Hydrocarbons ◽  
Wide Range

The ability to absorb oil hydrocarbons is inherent in microorganisms represented by various systematic groups. These include various types of micromycetes, yeast, and bacteria. The most active oil destructors are found among bacteria. They are characterized by the ability to absorb a wide range of hydrocarbons, including aromatic ones, have a high growth rate and, therefore, are of great practical interest. The restoration of oil-contaminated lands is currently one of the complex and at the same time little-studied object of reclamation. The article presents the results of studies of the adsorption capacity of hydrocarbon-oxidizing microorganisms of the genera Bacillus, Micrococcus and Rhodococcus and their oil-oxidizing activity after immobilization on zeolite and expanded clay in model conditions. It was noted that as a result of research work, strains of the microorganisms Rhodococcus, Micrococcus are better adsorbed on the surface of zeolite, expanded clay and at the same time have a high oil-oxidizing activity. Representatives of natural hydrocarbon-oxidizing microorganisms are characterized by high emulsification rates; the cultures of Rhodococcus erythropolis and Rhodococcus ruber have the highest emulsifying activity. This may indicate a high destructive activity of microorganisms. When assessing the degree of oil destruction after 60 days when introducing free cultures of microorganisms, it ranged from 32.84 to 64.94%, and in the variants with the introduction of immobilized cultures of microorganisms on zeolite, oil utilization was from 47.94 to 86.84%. When immobilized cells of hydrocarbon-oxidizing microorganisms were introduced onto expanded clay, the destruction ranged from 47.69 to 92.75%.

Dynamics of Exploited Whitefish Populations and their Management with Special Reference to the Northwest Territories

1975 ◽  
Vol 32 (3) ◽  
pp. 427-448 ◽  
Author(s):  
M. C. Healey
Keyword(s):  
Growth Rate ◽  
Population Size ◽  
Total Mortality ◽  
High Growth ◽  
Maximum Growth ◽  
High Growth Rate ◽  
Maximum Growth Rate ◽  
Stock Size ◽  
Slow Growth Rate ◽  
Wide Range

Available data on mortality, growth, reproduction, and stock size in exploited and unexploited populations of lake whitefish (Coregonus clupeaformis) are reviewed with a view to understanding the dynamics of exploited populations and improving their management. Natural mortality ranged from about 0.20 to 0.80 in unexploited populations. In exploited populations total mortality was as high as 0.94. Unexploited populations showed a wide range of growth rates. Growth rate increased with increasing exploitation, and growth rate in all heavily exploited populations was similar to the most rapid growth rate shown by unexploited stocks. Heavily exploited whitefish matured at a younger age and possibly also at a smaller size than those which were unexploited. Limited data on stock size suggest that although total population size declines under heavy exploitation, the vulnerable population remains of similar size.It is concluded that whitefish respond to fluctuations in population size through compensatory changes in growth rate, the difference between growth rate in a population and maximum growth rate is a measure of its scope for compensating for increased mortality. Populations with slow growth rate and low mortality should, therefore, have the best fishery potential, while those with high growth rate and high mortality have a low fishery potential. Further, it is possible to judge the fishery potential of a population or its stage of exploitation from relatively simple measurements of mortality, growth, age structure, and maturity.

scholarly journals AB0099 METHOTREXATE REDUCES THE INVASIVE ACTIVITIES OF PRIMARY RA SYNOVIAL FIBROBLASTS

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1349.2-1349
Author(s):  
C. R. Ng ◽  
K. Sheridan ◽  
S. Cowley ◽  
E. Dorris ◽  
D. Veale ◽  
...  
Keyword(s):  
Repeated Measures ◽  
High Growth ◽  
Synovial Fibroblasts ◽  
High Growth Rate ◽  
Research Centre ◽  
Tissue Destruction ◽  
Paired Samples ◽  
Wide Range ◽  
Proliferation And Apoptosis

Background:Rheumatoid Arthritis synovial fibroblasts (RASFs) are key player in tissue destruction via the production of a wide range of chemical reactions in the joint with high growth rate and resistance to mortality [1]. Methotrexate (MTX) is a dihydrofolate reductase inhibitor that attenuates inflammation within joints resulting in reduced cartilage and bone damage and is the anchor therapy for RA. Its mechanisms of action are thought to differ from its anti-proliferative effects and are known to include increased adenosine release (2), but may also involve alterations in intracellular methyl donor status resulting in alteration in DNA methylation and gene expression.Objectives:To investigate the effects of MTX on RASFs auto-aggressive activities, including invasion, migration, proliferation and apoptosis.Methods:RASF were derived from knee biopsies of RA patients taken at arthroscopy (n=9). Matrigel chambers were used to measure invasive activities. The cells were incubated with DMSO (control), 1μM or 10μM MTX for 96 hours. Wound healing (scratch assays) were used to measure migration. Proliferation and apoptosis was determined using BrdU and caspase-3/7 assays respectively. Significance was determined via repeated measures ANOVA using SPSS software.Results:Incubation with MTX resulted in significantly reduced invasive activity compared with DMSO control; 1μM (35%, p=0.006) and 10μM (58%, p=0.002) in paired samples. However MTX did not have significant effects on RASF migration, apoptosis or proliferation at either concentration.Conclusion:Our data reveals that MTX reduces the invasive potential of RASFs in vitro, this effect may contribute to the clinical efficacy of this agent. Further investigation will involve epigenome-wide methylation to determine if the DNA methylome of RASFs is altered by MTX.References:[1]Huber LC, et al. (2006) Rheumatol. 45(6):669-675.[2]Chan ES & Cronstein BN (2010) Nat Rev Rheumatol 6(3):175-178.Acknowledgments:This abstract arose from work funded by the National Children’s Research Centre, Our Lady’s Children’s Hospital, CrumlinDisclosure of Interests:None declared

scholarly journals Development of a tunable 3D wrinkled platfom for designing cellular three-dimensional communication networks

2021 ◽  
Author(s):  
Bethany R. Hughes
Keyword(s):  
Communication Networks ◽  
Three Dimensional ◽  
Cell Communication ◽  
Cellular Growth ◽  
Clinical Aspects ◽  
Wide Range ◽  
Cellular Communication Network ◽  
Potential Applications ◽  
A Cell ◽  
Washing Method

The study of cell-cell communication is hindered by the absence of a platform which is capable of specifically directing cellular growth while allowing examination of the communication between cells. In this thesis, a tuneable micro-to-nano scale wrinkled nonplanar platform was developed and optimized through the use of photolithography and a microfluidic washing method. The platform demonstrated the ability to create micro and nanowrinkled structures in a wide range of flow conditions. The developed platform was then used as a cell culture platform to investigate the spacing dependence of bovine fibroblasts. The identification of a critical bridging distance for bovine fibroblasts provided a means to optimized the platform for culturing a cellular communication network between bovine fibroblasts. The cellular network which resulted demonstrated, via FRAP (Fluorescence-recovery-after-photobleaching), the capacity for communication between cells. Creating multilevel length scaled structures on a tunable platform which directed cellular growth while maintaining communication presents potential applications in research, industry and clinical aspects.

scholarly journals Introduction of Dorper sheep into Australian rangelands: implications for production and natural resource management

2014 ◽  
Vol 36 (1) ◽  
pp. 85 ◽  
Author(s):  
Yohannes Alemseged ◽  
Ronald B. Hacker
Keyword(s):  
Natural Resource ◽  
Feeding Strategy ◽  
High Growth ◽  
Rapid Onset ◽  
High Growth Rate ◽  
High Fertility ◽  
Key Factors ◽  
Resource Degradation ◽  
Wide Range ◽  
Grazing Ecology

The growing popularity of the Dorper breed of sheep potentially may have implications for the ecological sustainability of the semiarid and arid rangelands of southern Australia. The implications are heightened by forecasts of a warming and drying climate in these rangelands, which may in itself place native vegetation under increasing stress. While the Dorper breed of sheep offers important production advantages, little is known from research under Australian conditions about their grazing ecology and management requirements from a natural resource perspective. Key factors identified from this review of literature from other countries include a high fertility and fecundity, a generalist feeding strategy, a high growth rate and a capacity to survive and reproduce under low-rainfall conditions. The wider range of plant species selected by the Dorper compared with the traditional Merino breed of sheep potentially creates both opportunities and risks for rangeland condition. Less selective grazing may reduce pressure on some species but the capacity to harvest sufficient nutrients over a smaller area could concentrate grazing and promote resource degradation. High reproductive efficiency under a wide range of seasonal conditions may lead to more rapid onset of overgrazing and will require close attention to both natural resources and animal marketing if resource degradation is to be avoided.

scholarly journals Development of a tunable 3D wrinkled platfom for designing cellular three-dimensional communication networks

2021 ◽  
Author(s):  
Bethany R. Hughes
Keyword(s):  
Communication Networks ◽  
Three Dimensional ◽  
Cell Communication ◽  
Cellular Growth ◽  
Clinical Aspects ◽  
Wide Range ◽  
Cellular Communication Network ◽  
Potential Applications ◽  
A Cell ◽  
Washing Method

The study of cell-cell communication is hindered by the absence of a platform which is capable of specifically directing cellular growth while allowing examination of the communication between cells. In this thesis, a tuneable micro-to-nano scale wrinkled nonplanar platform was developed and optimized through the use of photolithography and a microfluidic washing method. The platform demonstrated the ability to create micro and nanowrinkled structures in a wide range of flow conditions. The developed platform was then used as a cell culture platform to investigate the spacing dependence of bovine fibroblasts. The identification of a critical bridging distance for bovine fibroblasts provided a means to optimized the platform for culturing a cellular communication network between bovine fibroblasts. The cellular network which resulted demonstrated, via FRAP (Fluorescence-recovery-after-photobleaching), the capacity for communication between cells. Creating multilevel length scaled structures on a tunable platform which directed cellular growth while maintaining communication presents potential applications in research, industry and clinical aspects.

Recent Developments in SiC Homoepitaxy Using Dichlorosilane for High Power Devices

2010 ◽  
Vol 1246 ◽  
Author(s):  
Iftekhar Chowdhury ◽  
MVS Chandrasekhar ◽  
Paul B Klein ◽  
Joshua D Caldwell ◽  
Tangali Sudarshan
Keyword(s):  
Chemical Vapor ◽  
High Growth ◽  
High Growth Rate ◽  
Power Devices ◽  
X Ray ◽  
Carrier Lifetimes ◽  
Wide Range ◽  
Recent Developments ◽  
Morphological Defects ◽  
Site Competition

AbstractThick and high quality 4H-SiC epilayers have been grown in a vertical hot-wall chemical vapor deposition system at a high growth rate on (0001) 8 0 off-axis substrates. We discuss the use of dichlorosilane as the Si-precursor for 4H-SiC epitaxial growth as it provides the most direct decomposition route into SiCl 2, which is the predominant growth species in chlorinated chemistries. The RMS roughness of the films ranged from 0.5-2.0 nm with very few morphological defects (carrots, triangular defects, etc.) being introduced, while enabling growth rates of 30-100 μm/hr, 5-15 times higher than most conventional growths. A specular surface morphology was attained by limiting the hydrogen etch rate until the system was equilibrated at the desired growth temperature. Site-competition epitaxy was observed over a wide range of C/Si ratios, with doping concentrations as low as 2x10 14 cm -3 being recorded. X-ray rocking curves indicated that the epilayers were of high crystallinity, with linewidths as narrow as 7.8 arcsec being observed, while microwave photoconductive decay (μPCD) measurements indicated that these films had high injection (ambipolar) carrier lifetimes in the range of 2 μs. These films also appeared to be free of polytype inclusions.

Properties of thin film silicon, prepared at high growth rate in a wide range of thicknesses

2008 ◽  
Vol 354 (19-25) ◽  
pp. 2451-2454
Author(s):  
J. Kočka ◽  
T. Mates ◽  
M. Ledinský ◽  
H. Stuchlíková ◽  
J. Stuchlík ◽  
...  
Keyword(s):  
Thin Film ◽  
Growth Rate ◽  
High Growth ◽  
High Growth Rate ◽  
Thin Film Silicon ◽  
Wide Range

scholarly journals Controlled Autolysis and Enzyme Release in a Recombinant Lactococcal Strain Expressing the Metalloendopeptidase Enterolysin A

2004 ◽  
Vol 70 (3) ◽  
pp. 1744-1748 ◽  
Author(s):  
Rita M. Hickey ◽  
R. Paul Ross ◽  
Colin Hill
Keyword(s):  
Large Scale ◽  
Production Systems ◽  
Expression System ◽  
Fold Increase ◽  
Lytic Enzyme ◽  
Enzyme Release ◽  
Gram Positive Bacteria ◽  
Wide Range ◽  
Potential Applications ◽  
A Cell

ABSTRACT This study concerns the exploitation of the lytic enzyme enterolysin A (EntL), produced by Enterococcus faecalis strain DPC5280, to elicit the controlled autolysis of starter lactococci. EntL, a cell wall metalloendopeptidase secreted by some E. faecalis strains, can kill a wide range of gram-positive bacteria, including lactococci. The controlled expression of entL, which encodes EntL, was achieved using a nisin-inducible expression system in a lactococcal host. Zymographic analysis of EntL activity demonstrated that active enzyme is produced by the recombinant lactococcal host. Indeed, expression of EntL resulted in almost complete autolysis of the host strain 2 h after induction with nisin. Model cheese experiments using a starter strain in addition to the inducible enterolysin-producing strain showed a 27-fold increase in activity with respect to the release of lactate dehydrogenase in the strain overexpressing EntL, demonstrating the potential of EntL production in large-scale cheese production systems. Indeed, the observation that a wide range of lactic bacteria are sensitive to EntL suggests that EntL-induced autolysis has potential applications with a variety of lactic acid bacteria and could be a basis for probiotic delivery systems.

Sign in / Sign up

Export Citation Format

Share Document