Heat-acclimatised strains of Rhodopseudomonas palustris reveal higher temperature optima with concomitantly enhanced biohydrogen production rates

Controlled-environment experiments were conducted on Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedlings during their 1st year. Hardiness of foliage was assessed by visually estimating injury after freezing tests.Germinants (1 week) were unable to attain any freezing tolerance under 8-h days at 2 °C even after 9 weeks but were killed whenever ice formed. Their ability to supercool increased by 5 °C during this treatment. However, seedlings older than 3 weeks (1 to 2 cm of epicotyl) could develop true hardiness under the influence of either short days (less effective) or low positive temperatures, independently of lignification, bud setting, or entry into rest. Ability to acclimate increased gradually with age and was inversely related to growth and maturation, apparently because the latter processes had higher temperature optima. Photoperiod affected growth and bud formation only above about 15 °C but influenced hardiness at 1 °C. The optimum photoperiod for inducing hardiness was longer at low light intensities than at high ones, presumably because of a minimum requirement for photosynthesis.Interruption of the long inductive dark period with 15 min of red light (650 nm) caused a small decrease in hardiness and bud set and an increase in growth. This effect was not reversed, but was enhanced by an isoenergetic burst of far-red (FR) light immediately after. FR interruptions alone had no effect. Night frosts (−7 °C) caused significant dehydration and rapidly increased hardiness only if both the warm, short day and chilling "stages" had been supplied first and the daily supply of light continued.

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Bioprocess modelling of biohydrogen production by Rhodopseudomonas palustris: Model development and effects of operating conditions on hydrogen yield and glycerol conversion efficiency

Chemical Engineering Science ◽

10.1016/j.ces.2015.02.045 ◽

2015 ◽

Vol 130 ◽

pp. 68-78 ◽

Cited By ~ 29

Author(s):

D. Zhang ◽

N. Xiao ◽

K.T. Mahbubani ◽

E.A. del Rio-Chanona ◽

N.K.H. Slater ◽

...

Keyword(s):

Conversion Efficiency ◽

Rhodopseudomonas Palustris ◽

Model Development ◽

Operating Conditions ◽

Biohydrogen Production ◽

Hydrogen Yield ◽

Glycerol Conversion

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Effects of cellulose concentrations on the syntrophic interactions between Clostridium cellulovorans 743B and Rhodopseudomonas palustris CGA009 in coculture fermentation for biohydrogen production

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2015.05.135 ◽

2015 ◽

Vol 40 (35) ◽

pp. 11800-11808 ◽

Cited By ~ 15

Author(s):

Hongyuan Lu ◽

Patrick K.H. Lee

Keyword(s):

Rhodopseudomonas Palustris ◽

Biohydrogen Production ◽

Clostridium Cellulovorans

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Experimental Calibration of a Biohydrogen Production Estimation Model

Journal of Verification Validation and Uncertainty Quantification ◽

10.1115/1.4044664 ◽

2019 ◽

Vol 4 (2) ◽

Author(s):

Fernando G. Dias ◽

Jose V. C. Vargas ◽

Sam Yang ◽

Marcos P. Rosa ◽

Beatriz Santos ◽

...

Keyword(s):

Growth Rate ◽

Hydrogen Production ◽

Culture Media ◽

Biomass Concentration ◽

Element Model ◽

Biohydrogen Production ◽

Estimation Model ◽

Production Rates ◽

Experimental Calibration ◽

Microalgae Growth

Abstract A dynamic physics-based model developed for the prediction of biohydrogen production in a compact tubular photobioreactor (PBR) was calibrated experimentally. The spatial domain in the model was discretized with lumped control volumes and the principles of classical thermodynamics, mass, species, and heat transfer were combined to derive a system of ordinary differential equations, whose solution was the temperature and mass fraction distributions across the entire system. Two microalgae species, namely, Acutodesmus obliquus and Chlamydomonas reinhardtii strain cc125, were cultured in triplicate with different culture media via indirect biophotolysis. Measured biomass and hydrogen concentrations were then used to adjust the specific microalgae growth and hydrogen production rates in the model based on residual sum of squares (RSS) and the direct search method. Despite its simplicity, the presented volume element model was verified to well predict both hydrogen and biomass concentration over time. The microalgae growth rate for each species was determined as 2.16 μalga,0 s−1 and 0.91 μalga,0 s−1 for A. obliquus and C. reinhardtii strain cc125, respectively, where μalga,0 is the specific growth rate of Scenedesmus almeriensis for given temperature and irradiance. The adjusted maximum hydrogen production rates for the local nonmutant A. obliquus and for C. reinhardtii strain cc125 were 1.3 × 10−7 s−1 and 4.1 × 10−7 s−1. Consequently, these hydrogen production rates were 59 times and 19 times smaller, respectively, than that for the mutant C. reinhardtii strain cc849.

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Biohydrogen production beyond the Thauer limit by precision design of artificial microbial consortia

Communications Biology ◽

10.1038/s42003-020-01159-x ◽

2020 ◽

Vol 3 (1) ◽

Cited By ~ 1

Author(s):

İpek Ergal ◽

Oliver Gräf ◽

Benedikt Hasibar ◽

Michael Steiner ◽

Sonja Vukotić ◽

...

Keyword(s):

Renewable Energy ◽

Culture System ◽

Biohydrogen Production ◽

Microbial Consortia ◽

Production Rates ◽

Key Technology ◽

Precision Design ◽

Energy Science ◽

Drawing Board ◽

The Way

AbstractDark fermentative biohydrogen (H2) production could become a key technology for providing renewable energy. Until now, the H2 yield is restricted to 4 moles of H2 per mole of glucose, referred to as the “Thauer limit”. Here we show, that precision design of artificial microbial consortia increased the H2 yield to 5.6 mol mol−1 glucose, 40% higher than the Thauer limit. In addition, the volumetric H2 production rates of our defined artificial consortia are superior compared to any mono-, co- or multi-culture system reported to date. We hope this study to be a major leap forward in the engineering of artificial microbial consortia through precision design and provide a breakthrough in energy science, biotechnology and ecology. Constructing artificial consortia with this drawing-board approach could in future increase volumetric production rates and yields of other bioprocesses. Our artificial consortia engineering blueprint might pave the way for the development of a H2 production bioindustry.

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Biohydrogen Production by Immobilized Co-culture of Clostridium Butyricum and Rhodopseudomonas Palustris

Energy Procedia ◽

10.1016/j.egypro.2014.11.976 ◽

2014 ◽

Vol 61 ◽

pp. 834-837 ◽

Cited By ~ 11

Author(s):

Po-Min Kao ◽

Bing-Mu Hsu ◽

Kuan-Hao Huang ◽

Chi-Wei Tao ◽

Chia-Ming Chang ◽

...

Keyword(s):

Rhodopseudomonas Palustris ◽

Clostridium Butyricum ◽

Biohydrogen Production

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Nucleation of Disorder in Fe3Al Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061574 ◽

1967 ◽

Vol 25 ◽

pp. 312-313

Author(s):

P. R. Swann ◽

W. R. Duff ◽

R. M. Fisher

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Annealing Temperature ◽

Antiphase Domain ◽

Effect Of Temperature ◽

Domain Structures ◽

Transmission Electron ◽

Domain Boundaries ◽

Higher Temperature ◽

The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

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Application Of Electron Probe Analyses Of Minerals In Discussing The Relationship Between Ductile Deformation And Metamorphism

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100134855 ◽

1990 ◽

Vol 48 (2) ◽

pp. 250-251

Author(s):

Fan Guochuan ◽

Sun Zhongshi

Keyword(s):

Chemical Composition ◽

Shear Deformation ◽

Electron Probe ◽

General Rule ◽

Granulite Facies ◽

Ductile Deformation ◽

Higher Temperature ◽

Ductile Shear ◽

The Relationship ◽

Ductile Shear Deformation

Under influence of ductile shear deformation, granulite facies mineral paragenesis underwent metamorphism and changes in chemical composition. The present paper discusses some changes in chemical composition of garnet in hypers thene_absent felsic gnesiss and of hypersthene in rock in early and late granulite facies undergone increasing ductile shear deformation .In garnet fetsic geniss, band structures were formed because of partial melting and resulted in zoning from massive⟶transitional⟶melanocrate zones in increasing deformed sequence. The electron-probe analyses for garnet in these zones are listed in table 1 . The Table shows that Mno, Cao contents in garnet decrease swiftly from slightly to intensely deformed zones.In slightly and moderately deformed zones, Mgo contents keep unchanged and Feo is slightly lower. In intensely deformed zone, Mgo contents increase, indicating a higher temperature. This is in accord with the general rule that Mgo contents in garnet increase with rising temperature.

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