bluuebunny/crossref_metadata_2025_split huggingface dataset:
Downward Coupling between the Stratosphere and Troposphere: The Relative Roles of Wave and Zonal Mean Processes*
Authors: Perlwitz Judith , Harnik Nili 
Published: December 2004

Abstract
Wave and zonal mean features of the downward dynamic coupling between the stratosphere and troposphere are compared by applying a time-lagged singular value decomposition analysis to Northern Hemisphere height fields decomposed into zonal mean and its deviations. It is found that both zonal and wave components contribute to the downward interaction, with zonal wave 1 (due to reflection) dominating on the short time scale (up to 12 days) and the zonal mean (due to wave–mean-flow interaction) dominating on the longer time scale. It is further shown that the two processes dominate during different years, depending on the state of the stratosphere. Winters characterized by a basic state that is reflective for wave 1 show a strong relationship between stratospheric and tropospheric wave-1 fields when the stratosphere is leading and show no significant correlations in the zonal mean fields. On the other hand, winters characterized by a stratospheric state that does not reflect waves show a strong relationship only between stratospheric and tropospheric zonal mean fields. This study suggests that there are two types of stratospheric winter states, characterized by different downward dynamic interaction. In one state, most of the wave activity gets deposited in the stratosphere, resulting in strong wave–mean-flow interaction, while in the other state, wave activity is reflected back down to the troposphere, primarily affecting the structure of tropospheric planetary waves.
Study of direct oxygen transfer in a submerged culture
Authors: Sobotka M. , Votruba J. , Prokop A. 
Published: December 2004

AbstractAuf der Basis der Flotationstheorie der festen Partikel wurde in der Submerskultur der Mechanismus des direkten Sauerstoffübergangs in die Zelle unter den Bedingungen gegenseitiger Beeinflussung des Mikroorganismus mit der gasförmigen und der flüssigen Phase quantifiziert.
Bestimmung der Methanol‐Konzentration im stationären Zustand mit einer biologischen Methode
Authors: Nyeste L. , Kirchknopf L. , Báthory J. , Holló J. 
Published: December 2004

AbstractOn the base of measuring the respiration rate (HARRISON) a biological measuring method for determination of methanol concentration in stationary range was worked out. The method allows the determination of methanol concentrations up to 0.3 mg l−1 and is applicable for such cases, when microorganisms consume this substrate quickly (within a few minutes). If the methanol concentration in stationary range is known, it is possible to calculate the kinetic constants of the system.
Improved brewing of millet beer – (OYOKPO) and production of single cell proteins from the spent grain
Authors: Nkanga E. I. , Uraih N. 
Published: December 2004

AbstractThe improved method for preparing Oyokpo a Nigerian fermented beverage from millet, and the preparation of single cell proteins from the spent grain is described. Improvement of the brew was made by controlled malting, mashing and brewing with a pure culture of Saccharomyces cerevisiae. It had a reducing sugar content of 19.73 g/100 ml before fermentation and after fermentation 5.56% alcohol, 0.58 g/100 ml titratable acidity as acetic acid, a final pH of 4.2 and consisted of a yellowish clear liquid, slightly sour. The native brew had a reducing sugar content of 7.37 g/100 ml before fermentation and after fermentation, 2.40% alcohol, 0.43 g/100 ml titratable acidity, a final pH of 3.8 and consisted of a creamy yellowish liquid with a very sour taste. Fermented spent grain gave a higher protein yield compared to unfermented or ground millet. The lipids, proteins and crude fibre were 4.94%, 11.20% and 4.33% respectively for ground millet, 12,79%, 23.77% and 19.46% respectively for unfermented spent grain and 19.61%, 47.28% and 32.09% respectively for fermented spent grain. The high protein and fibre content of the fermented spent grain points to its potential as a feed supplement for ruminants.
Das Autoselect‐System – ein Automatensystem zur Selektion von Antibiotikaproduzenten. V. Achtfach‐Pipettierautomat
Authors: Steininger H. , Schicht G. , Peissker M. , Knöll H. 
Published: December 2004

AbstractAn automatic eightfold‐pipetter has been developed with the same basic unit as the diluter of the Autoselect‐system. The pipetter is fitted with eight pipettes on a bridge over the basic unit. By means of the pipettes a volume of 0.05 ml from eight tubes is exhauseted and delivered in the holes of a test plate. Both the test plate and a cassette with 64 tubes are located on a moving carriage. the test plate on the first floor and the cassette on the ground floor. If the pipettes transfer the samples from the tubes to the holes the distance between the pipettes must be changed by a special device from 20 to 30 mm, because the distance between the holes on the test plate differs from that of the tubes.For the transfer of 64 samples 2 minutes only are needed.
Das Autoselect‐System – ein Automatensystem zur Selektion von Antibiotikaproduzenten. VI. Achtfach‐Stanzautomat
Authors: Schicht G. , Steininger H. , Grosse P. , Knöll H. 
Published: December 2004

AbstractAn eightfold punch belonging to the Aùtoselect‐system is described. It is provided for the preparation of bioassay plates. From the agar of large quadratic test plates moving automatically on a carriage of the machine, 64 holes are made by eight punches. The punches arranged in a row over the test plate are lowered, if the carriage stops, and so they cut out and exhaust agar discs in a pattern of 8 × 8.
The role of mechanical shear and cavitation on the behaviour of molds
Authors: Placek J. , Ujcová E. , Musílková M. , Seichert L. , Fencl Z. 
Published: December 2004

AbstractThe morphology of filamentous microorganisms does essentially affect the production of metabolites. Agitating conditions may affect the morphology and for this reason the production of metabolites too.The following parameters it was found to have an influence:

Reynolds mixing number
impeller blade tips velocity
mean shear stress close to the impeller
impeller power consumption per unit volume
cavitation pressure drop
It were presumed three mechanisms for the mechanical effect on the microorganisms:

the direct impact of the impeller blades on the microorganisms‐collision
the shear stress in the liquid phase
a sharp pressure decrease behind the impeller blades‐cavitation
Mathematical relationships are developed for the different mechanisms.Using Aspergillus niger it is shown what morphological and physiological states of this microorganism are caused by mechanical straining and the conditions for the maximal production of citric acid are studied.Requirements for scale‐up are discussed.
Ethanol production from non‐grain feedstocks
Authors: Michaels St. L. , Blanch H. W. 
Published: December 2004

AbstractA general view of the possibilities of producing ethanol from sugar, starch and cellulose feedstocks is given.For the 3 variants net energy analysis of ethanol production and evaluation of costs are presented. With the exception of the case using molasses as feedstock the net energy balances are positive.The greatest possible net energy yield can be expected with sugar cane followed by sugar beets, wood and paper waste. Based on feedstock availability, net energy utilization and production costs, the most promising processes for producing ethanol from non‐grain feedstocks over the next 20 years will be those processes using fermentable sugars available from nongrain starchy materials, cellulosics and whey.The feedstock prices for cellulosics are low and if the developments in cellulose hydrolysis will lead to improve the ethanol yields from cellulose fermentation to nearer 90 percent of the theoretical value, cellulosic materials can become a good feedstock for ethanol production.
Spezielle Anwendungsmöglichkeiten mikrobieller Proteasen
Authors: Heitmann P. , Meyer D. 
Published: December 2004

AbstractA brief review of the most important properties and fields of application of microbial proteinases are presented. Special possibilities of an industrial utilization of these enzymes are discussed: in the photographic industry for the production and degradation of gelatin as well as for silverless photography, in the food industry for the improvement of the functional properties of proteins as well as for increasing their nutritive value, in organic synthesis for the production of peptides, and in sewage treatment plants for the stabilization of sludge.
Enzym‐Muster Methanol assimilierender Hefen in Abhängigkeit vom Kohlenstoff‐Substrat
Authors: Müller R. , Hofmann K. H. , Babel W. 
Published: December 2004

AbstractThe influence of the carbon substrates glucose and methanol on enzyme activities of the yeast Candida methylica was investigated by substrate‐shift experiments in discontinuous cultivation. Growth on glucose results in a repression of the enzymes necessary for methanol utilization. After depletion of glucose or addition of methanol these enzymes are derepressed or induced, respectively. Changes in the activity of enzymes of the intermediary metabolism turn out differently both in intensity and direction as a result of substrate‐shifts. The results suggest a basic change in the metabolism by growing Candida methylica in glucose or methanol.
Status and developments of animal cell technology using suspension culture techniques
Authors: Katinger H. W. D. , Scheirer W. 
Published: December 2004

AbstractIn this review the state of the art in animal cell technology, using suspension culture techniques is updated as far as the end of 1980. We have tried to discuss, on a broad basis, the current status and potential developments of both, the purely biological and the biochemical engineering aspects which may be important to improve the performance and design of animal cell technologies. The process economics could be considerably improved by the use of transformed animal cell substrates, the use of cheaper cultivation media and by methodological and engineering means. Most of these aspects are in the state of realization. Nevertheless, for a great variety of biological active substances which do not require so – or posttranslational processing, recombinant DNA‐techniques (e.g. genetic engineering) are a promising alternative for the production of animal cell derived substances.
Some aspects of fermentation as an unit process in chemical engineering
Authors: Mueller F. G. 
Published: December 2004

AbstractThere are described possibilities of scale up in stirred tank fermenters being based on known relations of mass‐, energy‐and heat transfer. The represented mathematical description shows the problems of the necessary scale up in the practice with the theory of similarity in the stirred tank fermenter. Relating on the method of RUSHTON for calculation of the energy capacity in different stirred fermenters the influence of the aeration is examined and confirmed with experimental results of the author. By the sysem of equations the known parameters of the aerobic fermenters can be calculated.
Effektivität von Modellierung und Optimierung mikrobieller Prozesse
Authors: Prause M. , Soyez K. 
Published: December 2004

AbstractThe aim of the technological treatment of microbial processes is the optimal working of the production plant. The treatment itself is to be seen as a process whose realization requires a certain amount of expenditure. The problem of optimization of this process can with certain restictions be approximately solved in a series of steps. After a general formulation of the problem explanations are given for two important and typical steps – the determination of the extend of modelling and the choice of production cultures.
Regulation of lysine biosynthesis in Brevibacterium flavum
Authors: Leite M. P. , Rukliša M. P. , Viesturs U. E. , Švinka J. E. 
Published: December 2004

AbstractL‐lysine synthesis pathway enzyme activities: β‐aspartate kinase (EC.2.7.2.4), diaminopimelate decarboxylase (EC.4.1.1.20) for two L‐lysine producing strains Brevibacterium flavum 22LD and RC‐115 were studied. It has been found that β‐aspartate kinase and diaminopimelate decarboxylase in the Br. flavum RC‐115 are less sensitive to feed‐back inhibition by lysine and threonine. It is supposed that desensitized β‐aspartate kinase in the Br. flavum RC‐115 can be determined by genetical changes of the regulatory properties of the β‐aspartate kinase.Auxotrophity in the locus of homoserine dehydrogenase was tested and no homoserine dehydrogenase (EC.1.1.1.3) activity was found in either strain.The combination of these both types of mutation supplemented by the lack of catabolic repression in the RC‐115 strain makes it an active lysine producer in the medium with high carbohydrates content.
Gewinnung und Charakterisierung von Prolidase aus, Escherichia coli B., I. Gewinnung des Enzyms
Authors: Friese E. , Ruttloff H. 
Published: December 2004

AbstractAn enzyme being able to hydrolize the imido linkage at the N‐terminal end of proline is isolated from E. coli B. This fact corresponds to the specifity of hydrolization of the animal prolidase. Enzyme synthesis within the cells of E. coli B is carried out independently from growth. Changed environmental factors may influence the formation rate of enzyme in a restricted way. A relatively high enzyme biosynthesis can be reached by cultivating the strain E. coli B at a temperature of 37°C as well as an initial pH‐value of the medium of 7.0 in submerged culture (400–500 rpm) By variation of the medium composition enzyme synthesis does not change considerably, however, biomass yield can be increased about 100% If mechanical cell desintegration is optimized by means of ultrasonic or vibration homogenisator the cell components may be easily released with a higher proline specific activity as animal prolidase.
Calorimetric Glucose Determination by Glucose Oxidase —Methylene Blue
Authors: Kirstein D. , Schilder L. , Kahrig E. 
Published: December 2004

AbstractThe reaction between glucose and methylene blue, catalyzed by glucose oxidase (GOD)was analysed calorimetrically.The amount of heat produced under saturating methylene blue concentrations ( > 10−2 mol/1)was measured with glucose concentration and time as parameters (kinetic procedure) Kinetic constants (pseudo one substrate kinetics) were derived from the experimental data: KM(glucose)= 1.18 × 10−3 mol/l and Vmax = 0.085 J/mg GOD min (3.89 · 10−6 mol/mg GOD min)Comparison of caloric with optical measurements gave an enthalpy of reaction of 22.52 kJ/mol. Considering the observed substrate inhibition, glucose determinations are possible up to glucose concentrations of 0.1 mol/l.
Untersuchungen zur chemischen Zusammensetzung der Lipidfraktion von Acinetobacter calcoaceticus
Authors: Müller H. , Voigt B. 
Published: December 2004

AbstractLipids were extracted from the cells of Acinetobacter calcoaceticus EB 10 C IMET B 395 grown on gas oil (Bp. 240–360 °C) with benzine/alcohol (80 : 20). The lipid‐hydrocarbon‐extract obtained by this extraction method was 18.4%. The extract was composed of hydrocarbons, waxes, phospholipids, fatty acids, glycerides, and ubiquinones. The main components among the lipids were waxes. The compositions of phospholipid, fatty acid, wax, and ubiquinone fractions were analysed.
Zur Kinetik der Nebenproduktbildung bei der Überproduktion von Citronensäure durch Saccharomycopsis lipolytica
Authors: Behrens U. , Schulze E. , Weissbrodt E. , Scheffel B. 
Published: December 2004

AbstractAfter exhaustion of the N‐sources the yeast S.l. excretes citric and isocitric acid with high rates without interferring in the postlogarithmic phase the intracellular production of reserve materials like polysaccharides and especially lipids. The synthesis of citric acids and of reserve materials are therefore autonomically proceeding processes inside of the cellsWith increasing lipid content the ergosterol content increasesThe utilization of the ergosterol rich yeasts as valuable byproduct of the citric acid production is discussed.
Ein mikrorechnersystem für fermentationseinrichtungen
Authors: Albrecht Ch. , Ichter K. R 
Published: December 2004

AbstractFor several years now, we can notice efforts in increasing the efficiency of microbial processes by means of more intensive scientific investigation of such processes. Essential prerequisites to it are improved possibilities for process monitoring (available sensors) as well as facilities for realtime processing of process information. In this paper a microcomputer system is represented, which has been constructed on the base of computing needs for fermentation. The computing needs for fermentation experiments are outlined and the structure of the microcomputer is described. As an example it is illustrated what tasks can be solved by this microcomputer in coupled operation with a laboratory fermentor.
Beitrag zur Optimierung des mechanischen Aufschlusses von Hefezellen
Authors: Luther H. , Schuster E. 
Published: December 2004

AbstractThe influence of technological variables on the cell disintegration of yeast suspensions by means of a ball mill and a high pressure homogenizer has been studied by measuring the electrical conductivity. The rate constants and half‐life periods are calculated. Regarding the production of protein isolates, the stipulation of optimal disintegration conditions requires a compromise between a degree of disruption as high as possible and a low destruction of the cell walls.By homogenizing, fragments of cell walls arise which are more uniform and better separable in comparison with the milling process. Therefore the mechanical breakage of yeast cells on a large scale should be carried out by the use of high pressure homogenizers.
Untersuchungen zum Anfangsstadium der enzymatischen Hydrolyse unterschiedlich vorbehandelter Linterscellulose
Authors: Philipp B. , Dan D. C. , Linow K.‐J , Polter E. , Schulz G. 
Published: December 2004

AbstractStarting from cotton linters cellulose modified in physical structure type of lattice, degree of order, state of swelling by different pretreatments, and from culture filtrates of Gliocladium spec., the initial stage of enzymatic hydrolysis of cellulose has been investigated. Especially with substrates of high degradability a considerable effect of stirring on rate of formation of soluble products was found. For linerization of yield‐vs‐time‐curves (% residue resp. 7percnt; solubles as a criterion for yield), a 2‐parameatric first order rate law was found to be suitable within a limited time interval, values of k1 were higher and for the accessible part of the substrate were lower in the initial stage of hydrolysis than in the later one. The MICHAELIS‐MENTEN‐constant kM has been determined for substrates of different physical structure after different times of reaction. Data found for kM indicated a stronger dependence of kM on reaction time than on physical structure of the substrate under conditions applied.
Ethanol from Zymomonas, a bacterium
Authors: Zajic J. E. , Maddux N. L. , Jones L. P. 
Published: December 2004

AbstractThirteen isolates ofZymomonas were analyzed for their ability to tolerate increasing concentrations of glucose and ethanol. In medium containing 5.0% (v/v) ethanol, four isolates grew well in 15.0% (w/v) glucose. Six cultures tolerated at least 6,0% ethanol. Of all the isolates, 7 preferred glucose and 4 preferred sucrose as a sugar substrate. In a nutrient medium containing mineral salts and high concentrations of pantothenate and biotin ethanol production for 2 isolates was approximately 7.0%. Continuous stirring and growth factors were responsible for this increased ethanol production.
Einfluß der limitation des wachstums von hefen auf den oxidativen stoffwechsel und die produktsynthese
Authors: Lozinov A. B. , Finogenova T. V. 
Published: December 2004

AbstractThe growth limitation of aerobic yeast cultures in the majority of cases involves a deep conversion of the metabolism and high changes in the functional state of the cellsThe excretion of metabolits as one of this changes of great importance and the other variations in the state of the cells are the consequence of functional alternations of several anabolic and catabolic processes.
Entwicklung von Berechnungsmodellen für Enzymreaktoren (Teil 1)
Authors: Setzermann U. , Vondran J. , Mohr K.‐H. 
Published: December 2004

AbstractIt has been developed a model for a continuous working enzyme‐reactor to determine the deviation of temperature and concentration in axial and radial direction. It's based on Partial Differential Equations for mass and enthalpy transfer. The model regards the specialities of kinetics of enzyme‐catalytic processes with respect to the reaction rate. A difference method had been choosen which provided applicable results with respect to characteristic quantities of the substance under corresponding initial and boundary conditions. Some pictures show the deviation of temperature and concentration.
A desk‐top computer coupled fermentation system for the study of microbial processes: Description and some applications
Authors: Hampel W. , Woehrer W. , Bach H. P. , Roehr M. 
Published: December 2004

AbstractThe configuration and hardware components of a desk‐top computer coupled system for bench‐top bioreactors are described. Examples of on‐line acquisition of several directly accessible environmental process parameters and computations of directly inaccessible state variables are presented. The system described offers great advantages in experiments for establishing sophisticated control algorithms and for studying the physiological behaviour of microbial populations.
Ein Laborkleinfermentorsystem für die biotechnologische Grundlagenforschungl—MTA‐Ausrüstung
Authors: Iske U. , Rost H.‐J. , Portius S. 
Published: December 2004

AbstractLaborfermentoren stellen ein grundlegendes Arbeitsmittel in der biotechnologischen Forschung dar, dessen Entwicklungsst and in entscheidendem Maße Leistungsfähigkeit und Effektivität der Forschungsprozesse bestimmt. Deshalb ist eng verbunden mit den stündig steigenden Anforderungen an Quantität und Qualität der Informationen aus den verschiedenen hierarchischen Niveaus biotechnologischer Prozesse die Entwicklung hoch instrumentierter leistungsfähiger Laborfermentorsyteme.Der Trend, biotechnologische Prozesse in ihrer Raum‐Zeit‐Ausbeute traditionellen chemischen Prozessen anzugleichen, führte zur Entwicklung von Fermentorsystemen mit neuen Wirkprinzipien zur Gewährleistung hoher Stoffäbertragungsleistungen. Mit der Realisierung derartiger Hochleistungsfermentoren in großtechnischen Dimensionen ist verbunden die Forderung nach leistungsfähigen Laborfermentoren für die Erarbeitung wissenschaftlicher Grundlagen als Basis für eine gesicherte Maßestabsäbertragung.Die Entwicklung eines 2,5 l Laborsterilfermentors mit hohen Stoffübertragungsleistungen stellt einen Beitrag zur Vervollständigung der gerätetechnischen Basis für die biotechnologische Grundlagenforschung dar.