scholarly journals Studies on Aerobaclllus Polymyxa IV. Factors Affecting the Production of Hydrogenase and the Hydrogenlyase Systems

1953 ◽  
Vol 6 (2) ◽  
pp. 190 ◽  
Author(s):  
WG Crewther
Keyword(s):  
Methylene Blue ◽  
Hydrogen Production ◽  
Yeast Extract ◽  
Magnesium Sulphate ◽  
Gaseous Hydrogen ◽  
Factors Affecting ◽  
Whole Wheat ◽  
Glucose Phosphate ◽  
Production Of Hydrogen ◽  
Peptone Yeast Extract Glucose

Once-washed cells of Aerobacillu8 polymyxa harvested from a medium containing peptone, yeast extract, glucose, phosphate, and magnesium sulphate, did not produce hydrogen from formate, glucose, or pyruvate nor was methylene blue reduced in the presence of gaseous hydrogen. Production of hydrogen from formate could be demonstrated in fermenting whole wheat mash and by once-washed cells of A.polymyxa grown on strained 10 per cent. wheat mash.

scholarly journals Recent Achievements in Microalgal Photobiological Hydrogen Production

Energies ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 7170
Author(s):  
Eleftherios Touloupakis ◽  
Cecilia Faraloni ◽  
Ana Margarita Silva Benavides ◽  
Giuseppe Torzillo
Keyword(s):  
Public Opinion ◽  
Hydrogen Production ◽  
Photosystem Ii ◽  
Chlamydomonas Reinhardtii ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Energy Transition ◽  
Gaseous Hydrogen ◽  
Fossil Energy ◽  
Production Of Hydrogen

It is well known that over the last 60 years the trend of long-lived greenhouse gas emissions have shown a strong acceleration. There is an increasing concern and a mounting opposition by public opinion to continue with the use of fossil energy. Western countries are presently involved in a so-called energy transition with the objective of abandoning fossil energy for renewable sources. In this connection, hydrogen can play a central role. One of the sustainable ways to produce hydrogen is the use of microalgae which possess two important natural catalysts: photosystem II and hydrogenase, used to split water and to combine protons and electrons to generate gaseous hydrogen, respectively. For about 20 years of study on photobiological hydrogen production, our scientific hopes were based on the application of the sulfur protocol, which indisputably represented a very important advancement in the field of hydrogen production biotechnology. However, as reported in this review, there is increasing evidence that this strategy is not economically viable. Therefore, a change of paradigm for the photobiological production of hydrogen based on microalgae seems mandatory. This review points out that an increasing number of microalgal strains other than Chlamydomonas reinhardtii are being tested and are able to produce sustainable amount of hydrogen without nutrient starvation and to fulfill this goal including the application of co-cultures.

Factors Affecting Isolation and Identification of Haemophilus vaginalis (Corynebacterium vaginale)

1979 ◽  
Vol 9 (1) ◽  
pp. 65-71
Author(s):  
Robert K. Bailey ◽  
Jack L. Voss ◽  
Rodney F. Smith
Keyword(s):  
Yeast Extract ◽  
Systems Analysis ◽  
Basal Medium ◽  
Gas Liquid Chromatography ◽  
Isolation And Identification ◽  
Factors Affecting ◽  
Proteose Peptone ◽  
Bifidobacteria Strain ◽  
Reference Strains ◽  
Peptone Yeast Extract Glucose

The rate of isolation of organisms resembling Haemophilus vaginalis (Corynebacterium vaginale) from vaginal specimens was not significantly affected by anaerobic versus carbon dioxide incubation atmospheres or whether specimens were inoculated on isolation media immediately after collection or after a delay of 6 h. Forty-one clinically isolated strains were provisionally divided into 30 H. vaginalis strains and 11 H. vaginalis -like (HVL) strains based on morphological and growth characteristics. The H. vaginalis strains were less reactive in API-20A identification test strips, (Analytab Products, Inc.) using Lombard-Dowell broth, than in a modified basal medium that contained proteose peptone no. 3 (Difco). The numbers and kinds of substrates fermented by 30 clinical and 2 reference strains of H. vaginalis varied among conventional, API, Minitek (Baltimore Biological Laboratory), and rapid buffered substrate fermentation systems. A greater number and variety of carbohydrates were fermented by the 11 HVL strains more consistently in all four test systems. Analysis of volatile and nonvolatile fermentation end products by gas-liquid chromatography did not reveal significant differences between the H. vaginalis and HVL strains. However, the latter group grew in peptone-yeast extract-glucose broth, whereas the H. vaginalis strains did not grow without the addition of starch to peptone-yeast extract-glucose. All of the reference and clinical strains were similar in their susceptibilities to a variety of antimicrobial compounds except sulfonamides, which inhibited the HVL strains and bifidobacteria but not the H. vaginalis strains. Sulfonamide susceptibility or resistance corresponded in part to the H. vaginalis and HVL-bifidobacteria strain reactions on selected conventional fermentation substrates. Susceptibility or resistance to sulfonamides and metronidazole in conjunction with fermentation tests is described to aid in the separation of H. vaginalis from other possibly unrecognized biotypes of H. vaginalis or other vaginal bacteria that presumptively resemble the organism. A human blood medium known as V agar was also of considerable value in distinguishing H. vaginalis from HVL strains, because only the H. vaginalis strains produced diffuse beta-hemolysis on V agar.

Characterization of a Polymeric Membrane for the Separation of Hydrogen in a Mixture with CO2

2016 ◽  
Vol 9 (1) ◽  
pp. 126-136 ◽  
Author(s):  
Dionisio H. Malagón-Romero ◽  
Alexander Ladino ◽  
Nataly Ortiz ◽  
Liliana P. Green
Keyword(s):  
Carbon Dioxide ◽  
Hydrogen Production ◽  
Test Performance ◽  
Low Cost ◽  
Time Lag ◽  
Polymeric Membrane ◽  
Biological Processes ◽  
Scanning Calorimetry ◽  
Environmentally Sustainable ◽  
Production Of Hydrogen

Hydrogen is expected to play an important role as a clean, reliable and renewable energy source. A key challenge is the production of hydrogen in an economically and environmentally sustainable way on an industrial scale. One promising method of hydrogen production is via biological processes using agricultural resources, where the hydrogen is found to be mixed with other gases, such as carbon dioxide. Thus, to separate hydrogen from the mixture, it is challenging to implement and evaluate a simple, low cost, reliable and efficient separation process. So, the aim of this work was to develop a polymeric membrane for hydrogen separation. The developed membranes were made of polysulfone via phase inversion by a controlled evaporation method with 5 wt % and 10 wt % of polysulfone resulting in thicknesses of 132 and 239 micrometers, respectively. Membrane characterization was performed using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), atomic force microscopy (AFM), and ASTM D882 tensile test. Performance was characterized using a 23 factorial experiment using the time lag method, comparing the results with those from gas chromatography (GC). As a result, developed membranes exhibited dense microstructures, low values of RMS roughness, and glass transition temperatures of approximately 191.75 °C and 190.43 °C for the 5 wt % and 10 wt % membranes, respectively. Performance results for the given membranes showed a hydrogen selectivity of 8.20 for an evaluated gas mixture 54% hydrogen and 46% carbon dioxide. According to selectivity achieved, H2 separation from carbon dioxide is feasible with possibilities of scalability. These results are important for consolidating hydrogen production from biological processes.

scholarly journals Hydrogen production from water electrolysis: role of catalysts

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Shan Wang ◽  
Aolin Lu ◽  
Chuan-Jian Zhong
Keyword(s):  
Hydrogen Production ◽  
Water Splitting ◽  
Noble Metal ◽  
Active Sites ◽  
Current Knowledge ◽  
Low Cost ◽  
Critical Role ◽  
Water Electrolysis ◽  
Efficient Production ◽  
Production Of Hydrogen

AbstractAs a promising substitute for fossil fuels, hydrogen has emerged as a clean and renewable energy. A key challenge is the efficient production of hydrogen to meet the commercial-scale demand of hydrogen. Water splitting electrolysis is a promising pathway to achieve the efficient hydrogen production in terms of energy conversion and storage in which catalysis or electrocatalysis plays a critical role. The development of active, stable, and low-cost catalysts or electrocatalysts is an essential prerequisite for achieving the desired electrocatalytic hydrogen production from water splitting for practical use, which constitutes the central focus of this review. It will start with an introduction of the water splitting performance evaluation of various electrocatalysts in terms of activity, stability, and efficiency. This will be followed by outlining current knowledge on the two half-cell reactions, hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), in terms of reaction mechanisms in alkaline and acidic media. Recent advances in the design and preparation of nanostructured noble-metal and non-noble metal-based electrocatalysts will be discussed. New strategies and insights in exploring the synergistic structure, morphology, composition, and active sites of the nanostructured electrocatalysts for increasing the electrocatalytic activity and stability in HER and OER will be highlighted. Finally, future challenges and perspectives in the design of active and robust electrocatalysts for HER and OER towards efficient production of hydrogen from water splitting electrolysis will also be outlined.

scholarly journals A Process for Hydrogen Production from the Catalytic Decomposition of Formic Acid over Iridium—Palladium Nanoparticles

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3258
Author(s):  
Hamed M. Alshammari ◽  
Mohammad Hayal Alotaibi ◽  
Obaid F. Aldosari ◽  
Abdulellah S. Alsolami ◽  
Nuha A. Alotaibi ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Formic Acid ◽  
Activated Charcoal ◽  
Palladium Nanoparticles ◽  
Room Temperature ◽  
Catalytic Decomposition ◽  
Conversion Yield ◽  
Production Of Hydrogen ◽  
Commercial Applications

The present study investigates a process for the selective production of hydrogen from the catalytic decomposition of formic acid in the presence of iridium and iridium–palladium nanoparticles under various conditions. It was found that a loading of 1 wt.% of 2% palladium in the presence of 1% iridium over activated charcoal led to a 43% conversion of formic acid to hydrogen at room temperature after 4 h. Increasing the temperature to 60 °C led to further decomposition and an improvement in conversion yield to 63%. Dilution of formic acid from 0.5 to 0.2 M improved the decomposition, reaching conversion to 81%. The reported process could potentially be used in commercial applications.

scholarly journals Iridium Complex Catalyzed Hydrogen Production from Glucose and Various Monosaccharides

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 891
Author(s):  
Ken-ichi Fujita ◽  
Takayoshi Inoue ◽  
Toshiki Tanaka ◽  
Jaeyoung Jeong ◽  
Shohichi Furukawa ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Catalytic System ◽  
Catalytic Reaction ◽  
Hydrogen Gas ◽  
Water Soluble ◽  
Starting Material ◽  
Iridium Complex ◽  
Production Of Hydrogen ◽  
Bipyridine Ligand

A new catalytic system has been developed for hydrogen production from various monosaccharides, mainly glucose, as a starting material under reflux conditions in water in the presence of a water-soluble dicationic iridium complex bearing a functional bipyridine ligand. For example, the reaction of D-glucose in water under reflux for 20 h in the presence of [Cp*Ir(6,6′-dihydroxy-2,2′-bipyridine)(H2O)][OTf]2 (1.0 mol %) (Cp*: pentamethylcyclopentadienyl, OTf: trifluoromethanesulfonate) resulted in the production of hydrogen gas in 95% yield. In the present catalytic reaction, it was experimentally suggested that dehydrogenation of the alcoholic moiety at 1-position of glucose proceeded.

scholarly journals Enhanced hydrogen production of Rhodobacter sphaeroides promoted by extracellular H+ of Halobacterium salinarum

2021 ◽  
Vol 71 (1) ◽  
Author(s):  
Jiang-Yu Ye ◽  
Yue Pan ◽  
Yong Wang ◽  
Yi-Chao Wang
Keyword(s):  
Hydrogen Production ◽  
Production Rate ◽  
Rhodobacter Sphaeroides ◽  
Coupled System ◽  
Purple Membrane ◽  
Halobacterium Salinarum ◽  
Control Group ◽  
Hydrogen Production Rate ◽  
Production Of Hydrogen ◽  
The Impact

Abstract Purpose This study utilized the principle that the bacteriorhodopsin (BR) produced by Halobacterium salinarum could increase the hydrogen production of Rhodobacter sphaeroides. H. salinarum are co-cultured with R. sphaeroides to determine the impact of purple membrane fragments (PM) on R. sphaeroides and improve its hydrogen production capacity. Methods In this study, low-salinity in 14 % NaCl domesticates H salinarum. Then, 0–160 nmol of different concentration gradient groups of bacteriorhodopsin (BR) and R. sphaeroides was co-cultivated, and the hydrogen production and pH are measured; then, R. sphaeroides and immobilized BR of different concentrations are used to produce hydrogen to detect the amount of hydrogen. Two-chamber microbial hydrogen production system with proton exchange membrane-assisted proton flow was established, and the system was operated. As additional electricity added under 0.3 V, the hydrogen production rate increased with voltages in the coupled system. Results H salinarum can still grow well after low salt in 14% NaCl domestication. When the BR concentration is 80 nmol, the highest hydrogen production reached 217 mL per hour. Both immobilized PC (packed cells) and immobilized PM (purple membrane) of H. salinarum could promote hydrogen production of R. sphaeroides to some extent. The highest production of hydrogen was obtained by the coupled system with 40 nmol BR of immobilized PC, which increased from 127 to 232 mL, and the maximum H2 production rate was 18.2 mL−1 h−1 L culture. In the 192 h experiment time, when the potential is 0.3 V, the hydrogen production amount can reach 920 mL, which is 50.3% higher than the control group. Conclusions The stability of the system greatly improved after PC was immobilized, and the time for hydrogen production of R. sphaeroides significantly extended on same condition. As additional electricity added under 0.3 V, the hydrogen production rate increased with voltages in the coupled system. These results are helpful to build a hydrogen production-coupled system by nitrogenase of R. sphaeroides and proton pump of H. salinarum. Graphical abstract

PRODUCTION AND PROPERTIES OF 2,3-BUTANEDIOL: IX. THE EFFECT OF VARIOUS NUTRIENT MATERIALS ON THE FERMENTATION OF STARCH BY AEROBACILLUS POLYMYXA

1946 ◽  
Vol 24f (1) ◽  
pp. 29-38 ◽  
Author(s):  
Sybil B. Fratkin ◽  
G. A. Adams
Keyword(s):  
Wheat Flour ◽  
Yeast Extract ◽  
Corn Steep Liquor ◽  
Wheat Gluten ◽  
Wheat Starch ◽  
Whole Wheat Flour ◽  
Beneficial Effects ◽  
Whole Wheat ◽  
Steep Liquor ◽  
Starch Medium

Wheat starch is a poor medium for fermentation by Aerobacillus polymyxa. The solubles recovered from the separation of starch and gluten in patent flour enhance the fermentation but not as effectively as the similar fraction from whole wheat flour. Addition of supplements is necessary for a satisfactory yield of products in a reasonable length of time. Wheat gluten has no stimulatory effect but bran and shorts are both effective, the latter being slightly superior. An 8% starch medium fortified with the solubles from whole wheat required a 2.5% supplement of shorts to bring fermentation by A. polymyxa to 90% completeness in 72 hr.Of the various supplements tested, a 1% addition of malt sprouts proved to be the most effective, fermentation being 90% complete in 72 hr. Shorts, bran, Cerogras (dehydrated young oats), alfalfa, soya beans, yeast extract, and corn-steep liquor follow in order of decreasing effectiveness.The solubles from whole wheat when ashed have no beneficial effects on the fermentation of starch by A. polymyxa.

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