bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biodegradability of swine effluents II. Kinetics of pollutants removal
Authors: Oliveira J. S. , Costa M. L. , Rodrigues A. , Menezes J. G. A. , Borié M. C. 
Published: December 2004

AbstractSome aspects of the kinetics of bioremoval of pollutants during biodegradation of swine‐breeding waste waters are studied and a biphasic model is proposed. The concentration of nitrogen and phosphorus compounds during the process is followed. Following a previous contribution on the same subject, the aspects of dilution of those effluents are discussed, and it is proposed to treat raw effluents, in spite of the reduction of possible biostatic actions. Dilution will be acceptable only if strong inhibitory effects are observed.
Modellierung der enzymatischen Cellobiosehydrolyse – Vergleich linearer und nichtlinearer Parameterbestimmung
Authors: Bauer F. , Kude J. 
Published: December 2004

AbstractExperimental kinetic data (initial rate and high conversion) on the hydrolysis of cellobiose by 1,4‐β‐glucosidace (Gliocladium sp.) have been analysed and a competitive inhibition by glucose has been proposed. The determination of kinetic parameters from integral data is based upon algorithms for non‐linear optimization and numerical integration. The values of kinetic constants \documentclass{article}\pagestyle{empty}\begin{document}$(v_{\max } = 1.02\frac{{\mu {\rm M}_{{\rm glucose}} }}{{{\rm mg}_{{\rm protein}} \cdot \min }},K_M = 2.6{\rm mM/l, and }K_P = 1.2{\rm mM/l)}$\end{document} agree well with the initialrate results. An important distinction is the confidence limit of parameters. Linear regression analysis shows a virtual accuracy and can lead to wrong conclusions.
Untersuchungen zur Thermostabilität immobilisierter Invertase
Authors: Mansfeld J. , Schellenberger A. 
Published: December 2004

AbstractInvertase from baker's yeast (Saccharomyces cerevisiae) was covalently bound via glutaraldehyde to a macroporous polystyrene anion‐exchanger, silica, and porous glass. The thermal stability of the enzyme‐matrix complexes was found to be higher than that of soluble invertase, increasing in the order given above.The immobilization of invertase to the polystyrene anion‐exchanger by benzoquinonen and trichlorotriazine provided enzyme derivatives with lower thermal stability compared to the soluble enzyme.The thermal inactivation of all invertase‐matrix complexes is characterized by a biphasic course. The inactivation process is well described by a model of ULBRICH and SCHELLENBERGER [1] which is based on the assumption of two differently stable enzyme fractions each of which being inactivated by a first‐order reaction. This model proved to be appropriate also for the description of the thermal inactivation in the presence of substrate.
Gas balance method for testing of microbial growth efficiency after carbon substrate pulse
Authors: Baburin L. A. , Shvinka I. E. , Ruklisha M. P. , Viesturs U. E. 
Published: December 2004

AbstractThe present paper deals with the analysis of the amount of oxygen utilized for oxidation of a small dose of carbon substrate in carbon limited Brevibacterium flavum culture. The ratio of the measured oxygen consumption (mo2) to the amount of added carbon substrate (ms) gives a stoichiometric coefficient of the biological oxidation equation. A linear relationship between mo2 and ms was observed. To compare the efficiency of different carbon substrate utilization there has been introduced a normalized value β = m/m. There exists a simple relationship between β and the thermodynamical growth efficiency η The theoretical considerations are proved by experimental results with β, η and Yx/s in a chemostat culture at various medium flow rates.
Der substratlimitierte pH‐Auxostat – Eine neue Methode zur kontinuierlichen Kultur
Authors: Büttner R. , Uebel B. , Genz I. 
Published: December 2004

AbstractA method for continuous cultivation of microorganisms is demonstrated, the substrate limited pH‐auxostat. The limiting substrate only is added with constant velocity. In this culture the cells grow with high utilization of the limiting substrate and with the highest specific growth rate possible at the given conditions. Yield coefficients and dilution rates of stable K+‐limited steady states in yeast cultures with different pH‐values and biomass concentrations were measured.
Autolysis of disintegrated cells of the yeast saccharomyces cerevisiae
Authors: Běehalová B. , Beran K. 
Published: December 2004

AbstractOptimum conditions for autolysis of disintegrated cells of S. cerevisiae are at 50–53°C and pH 5.5; the process is terminated after 6 h. In the presence of sodium chloride (3–5%) the autolysis is complete after 5 h. The yield of autolysis of disintegrated yeast cells is about 70% of autolytic product per yeast dry weight. The product obtained after centrifugation, filtration and drying has very good sensoric and physical properties.
Zur Gewinnung von Ubichinon‐10 aus Acetobacter methanolicus IMET B 346
Authors: Worbs M. , Voigt B. 
Published: December 2004

AbstractMixtures of acetone/water (93 : 7 ··· 90 : 10, v/v) are favoured solvents for the extraction of ubiquinone‐10 from Acetobacter methanolicus IMET B 346. Using these solvent mixtures ubiquinone‐10 was extracted nearly completely. Other lipids were extracted partially. Extracts were obtained by optimal conditions with a ubiquinone content > 5%.
Microbial recycling of mineral waste products
Authors: Bosecker K. 
Published: December 2004

AbstractThe applicability of biotechnological methods to metal recovery from non‐sulfide industrial waste products (slag, galvanic sludge, filter‐press residue, filter dust, and fly ash) was investigated. From some products, copper, chromium, zinc or vanadium were completely extracted by sulfuric acid produced by Thiobacillus thiooxidans. The efficiency of bacterial metal solubilization varied depending on the type of waste material and on the pulp density. Stepwise increase of pulp density promoted bacterial growth and activity, resulting in metal concentrations of 6.6 g Cu/l, 6.3 g V/l, 24.4 g Zn/l or 21 g Cr/l in the leaching medium. In some cases bacterial leaching was as effective as chemical leaching with sulfuric acid. The efficiency of both processes is considered. In principal, bacterial metal recovery from industrial waste products seems to be feasible and may contribute to an increase in future supplies of raw materials, as well as to detoxification of industrial waste products resulting in reduced environmental pollution problems.
High performance liquid chromatography and biotechnological application of several oxidoreductases
Authors: Kovář J. 
Published: December 2004

AbstractThis paper describes our experience with the use of high performance liquid chromatography in the analysis and preparation of several NAD‐dependent dehydrogenases and oxygen‐dependent oxidases. The chromatographic materials tested were from Pharmacia (Sweden), LKB (Sweden) and Lachema (Czechoslovakia), the columns were attached to the fast protein liquid chromatographic (FPLC) system from Pharmacia. The preparative use of high performance ion exchange, molecular sieve and hydrophobic interaction chromatographies as well as of chromatofocusing made it possible to prepare tens of milligrams of completely pure enzymes in several hours. In most cases a combination of two high performance methods was sufficient to yield a homogeneous enzyme. The purified enzymes were used as analytical reagents for determining the concentrations of several metabolites and activities of some enzymes. A biotechnological application of immobilized alcohol dehydrogenase for the production of reduced nicotineadenine dinucleotide from the oxidized form of the coenzyme is discussed in a greater detail.
Ratio of heat production to oxygen consumption during the cell cycle of candida maltosa EH 15 grown on ethanol
Authors: Minkevich I. G. , Baumann F. , Rogge G. , Heinritz B. 
Published: December 2004

AbstractThe experimental technique for measurement of microbial culture heat evolution directly in fermenter has been described and its correctness analysed. Heat‐to‐oxygen ratio, Q0, of synchronized yeast culture in the absence of fermentative metabolism has been found to be practically independent of a cell cycle phase and close to the theoretical constant predicted by the mass‐energy balance theory. The collection of literature data on the heat‐to‐oxygen ratio is given. Energetic properties of cell biomass are discussed on the basis of the obtained and the surveyed values of Q0.
O‐acetyl cleavage by arthrobacter citreus
Authors: Fuska J. , Khandlová A. , Šturdíková M. , Proksa B. 
Published: December 2004

AbstractAbility of deacetylation of Arthrobacter citreus (ATCC 11 624) was studied on three different types of substrates: 4,27‐Di‐O‐acetyl‐withaferin A, calycotomine derivatives and isoindolo/1,2‐b//3/benz‐azepine‐5‐one derivative. Only O‐acetyl groups were cleaved by this strain, N‐acetyl group was not attacked. This deacetylation was not regioselective; by hydrolysis of racemic acetates there was only slight stereospecificity observed. As this reaction took a short time and afforded high yields under moderate conditions it may be useful in organic chemistry and/or in the structure elucidation of natural products.
Biosynthesis of protein by microscopic fungi in solid state fermentation. II. Optimization of aspergillus oryzae A. or. 11 cultivation for protein enrichment of starchy raw materials
Authors: Czajkowska D. , Ilnicka‐Olejniczak O. 
Published: December 2004

AbstractStudy was made of the effect of medium humidity, source and dose of nitrogen, dose of phosphorus, dose of inoculum and aeration on protein biosynthesis by strain Aspergillus oryzae A. or. 11 in solid state fermentation. It was found that for a maximal protein yield the medium ought to contain about: 60% of water, 36% of starchy raw materials d. m. (e.g. 28.8% of coarse rye meal and 7.2% of beet pulp), 0.85% of nitrogen sources (1.6% of (NH4)2SO4 and 1.1% of urea), and 0.35% of phosphorus source (1.3% of KH2PO4). pH of medium should be near 6.5. The dose of inoculum should not be lower than 108 spores/100 g medium.The duration of culture ought to be 20–22 h at 30–35°C, with aeration at least 40 dm3 of air/h × 1000 g medium. Under these conditions the protein yield is about 6.0–6.3 g/100 g of starting medium d.m. at the cost of utilization of about 25 g total carbohydrates.
The effect of culture conditions on proteolytic productivity of lipolytic microorganism
Authors: Maliszewska I. , Sroka Z. 
Published: December 2004

AbstractThe best proteolytic productivity of Pseudomonas fluorescens was observed when maltose and 5% peptone were in the medium. The optimal temperature was found to be 28°C.The pH values in the range of 4.0 to 8.6 have not influenced the enzyme production.The best proteinase cell activity (A) was in the early stage of culture (24–48 hours).
A comparison between the fermentative activities of free and Ca‐alginate‐entrapped cells of saccharomyces cerevisiae
Authors: Richter K. , Rühlemann I. , Becker U. , Berger R. 
Published: December 2004

AbstractThe continuous ethanol production by free and Ca‐alginate‐entrapped cells of the yeast Saccharomyces cer. IBT H 191 was investigated in a membrane reactor and in a CSTR, respectively. An empiric productivity model for free‐cell fermentation was found to be valid for immobilized cells if no external diffusion resistance existed within the reactor. In such a case the fermentative power of the immobilized cells was identical with this one of the free cells. A change of the ethanol‐tolerance behaviour of the cells as a result of the cell‐immobilization did not occur.
Construction of a promoter‐probe vector for the methanol‐utilizing bacterium acetobacter methanolicus MB 58
Authors: Schröder R. , Engel J. , Chistoserdov A. Y. , Tsygankov Y. D. 
Published: December 2004

AbstractWe report here the construction of a promoter‐probe vector, pRS2, which can be utilized in either Acetobacter methanolicus MB 58 or Escherichia coli due to the presence of broad‐host‐range replicon RSF 1010. The vector provides several unique restriction sites for promoter cloning as well as resistance markers for the selection of transformants. The promoter‐probe vector was constructed by inserting an EcoRI‐SalI‐polylinker fragment of pUC 19 into EcoRI/SalI digested pMK 16. The resulting plasmid, pRS1, was cloned into the unique EcoRI site of the broad‐host‐range plasmid RSF 1010.The vector was used to clone promoter‐containing sequences derived from the A. methanolicus MB 58 chromosome as well as the E. coli lac‐promoter.
Immobilization of enzymes on porous silica supports
Authors: Łobarzewski J. , Wojcik A. , Błaszczynska T. 
Published: December 2004

AbstractFour silica supports differing in pore dimensions were activated by treatment with SiCl4 and then with ethylenediamine to obtain alkylamine groups on the silica surface. Three enzymes, peroxidase from cabbage, glucoamylase from Aspergillus niger C and urease from soybean were immobilized on these supports using glutaraldehyde as coupling agent. It was found that the protein content, the retained enzymatic activity and the storage stability of the silica supported enzymes were considerably affected by support pore size and enzyme molecular weight, the factors which are supposed to alter protein distribution inside the support pores. The highest activity was found for peroxidase and glucoamylase attached to the silica with the widest pores, but their loss in activity during storage was considerable. The urease retained less activity after immobilization, but its storage stability was excellent.
Insoluble chromolytic substrates for the determination of proteolytic activity
Authors: Šafařík I. 
Published: December 2004

AbstractNew insoluble chromolytic substrates for the determination of proteolytic activity were prepared by incorporation of dyed proteins into the structure of calcium sulphate dihydrate. The prepared substrates could detect approximately 0.25–1.0 μg of trypsin per ml. The spontaneous leakage of dyed substances in water solutions was negligible.
The effects of some inorganic salts on the ethanol fermentation of Juniper berry sugars
Authors: Veljković V. B. , Lazić M. L. , Rutić D. J. , Stanković M. Z. 
Published: December 2004

AbstractAmmonium and phosphate ions added to water extracts of juniper berries in optimum concentrations of about 70 and 35 mM, respectively, ensure a maximum ethanol yield of about 90% of the theoretical one in 16–18 hour fermentation. Magnesium ions have a slightly negative effect on the ethanol yield.
Gerätesystem zur Massenspektrometrischen Prozeßüberwachung in der Fermentationstechnik
Authors: Iske U. , Schön G. , Jechorek M. , Rost H.‐J. 
Published: December 2004

AbstractA quadrupol mass spectrometer QMS c 300 developed and manufactured from the workshops of the Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen, has been cuppled with a 12 l laboratory steril fermenter. The QMS apparatus is provided with 3 different possibilities for sampling. Via a dynamic air input system the discharged air of the fermenter can be analyzed continuously. The static sampling input allows the off‐line measurement of gaseous and volatile compounds. Special membran samplers are used for measurements of volatile and gaseous substrates and microbial metabolites in the fermentation broth. The samplers can be adopted in the reactor vessel directly analogous to the pH and pO2‐electrodes.
Prozeßtechnische Untersuchungen zur Ausschöpfung mikrobieller Leistungsgrenzen
Authors: Pöhland D. , Klappach G. , Hühn J. , Schurig K.‐H. 
Published: December 2004

AbstractThe knowledge of the upper limits of growth rate and cell density is necessary to define the maximum possible productivity of a growth process. After a brief survey of the theoretical basis of microbial growth in dependence of mass transfer of oxygen and rheological properties of fermentation medium recent experimental results on the influence of higher pressure in the fermenter, of different substrate and dissolved oxygen concentrations on growth rate and yield coefficients of methanol utilizing bacteria are presented. Also some correlations between cell concentration and viscosity of fermentation broth are considered.
Quasikontinuierliche Bestimmung der Alkoholkonzentration in Fermentationsmedien
Authors: Geppert G. , Hanschmann G. , Thielemann H. 
Published: December 2004

AbstractA measuring device for the quasicontinuous determination of volatile substances in aqueous liquids, especially alcohols (methanol or ethanol) in fermentation media is presented. The working principle and the construction of this instrument are described. Measurements are possible in a concentration range between 0.1 and 150 g/l. The measuring device is suited for industrial processes as well as for laboratory use.
Isolation of auxotrophic mutants and development of conjugation system in KISR methylotrophs
Authors: Kadri M. , Al‐Salameen F. , Haditirto S. , Engel J. 
Published: December 2004

AbstractIsolation of auxotrophic mutants and conjugal transfer of plasmids are successfully demonstrated in four obligate methylotrophic strains isolated at Kuwait Institute for Scientific Research (KISR)Out of 11 auxotrophic, mutants, three required methionine and two leucine. Complete transfer of plasmid R68.45 from Pseudomonasto KISR methylotrophs and vice versa have been achieved with a low transfer rate.
Role of biotechnology in the sphere of veterinary vaccine products
Authors: Sólyom F. 
Published: December 2004

AbstractDuring the last century two kinds of methods were developed in the field of vaccine production: those of inactivated and of attenuated vaccines. Both of them contained the whole microorganism. Thus, postvaccinal lesion even sporadically might occur. In the last 15 years, due to the development of molecular biology and of genetic engineering, novel technologies of vaccine production dissimilar to the former ones were and are evolved, which are as follows: subunit, synthetic, recombinant, genetically engineered and anti‐idiotype vaccines. Apart from genetically engineered vaccine, vaccines produced by means of new methods contain merely the immunocompetent protein particle of microorganism, thus, postvaccinal lesion should not be expected using vaccines of these kind. Vaccines produced by means of primary biotechnologic methods were put on the market in 1983 and introduction of 25 to 30 vaccines is expected until 1992. Approximately 145 companies, institutes are dealing worldwide with development of veterinary vaccines and they are in competition, with enormous investment capital, for accession of share as much as possible in vaccine market of about 550 million dollars.
Investigation of the connection between the electrophoretic mobility (EPM) of microorganisms and their capability of metal uptake
Authors: Iske U. , Hübner K. , Herold W. 
Published: December 2004

AbstractThe electrophoretic mobility of microorganisms (EPM) as a measure of their electric surface charge was determined as a function of different milieu conditions with the aid of the “Parmoquant 2” cell electrophoresis apparatus manufactured by CARL ZEISS Jena.The object of these researches was to examine the influence of the electric surface charge of microorganisms on their metal loading capacity. The results show a direct correlation between the electric surface charge or the EPM of microorganisms and their maximum metal loading capacity. Cells with a high negative surface also posses a high metal binding capacity. On the other side only a negligible metal uptake can be observed at the isoelectric point of the microorganisms (EPM = 0). The method of cell electrophoresis proved suitable to analyze complex interactions between microorganisms and heavy metal ions.
Influence of cytochrome composition on the energy conservation of acinetobacter calcoaceticus 69‐V
Authors: Loffhagen N. , Babel W. 
Published: December 2004

AbstractAcinetobacter calcoaceticus 69‐V contained cytochromes b, o, d and traces of cytochrome a1 after growth on ethanol. Cytochromes o, d, and a1 are known to be potentially capable of functioning as terminal oxidases. After growth on acetate only smaller amounts of cytochromes b and o were detectable. Cytochrome spectra of acetate plus glucose‐grown cells resembled more those of ethanolgrown cells. Cytochrome spectra of acetate plus ethanol‐grown cells were more similar to those of acetate‐grown cells but already showed small amounts of cytochrome d.Ethanol‐grown cells were energized only by the oxidation of glucose. But the velocity of ATP synthesis was so low that the P/O quotient amounted to practically zero. The stoichiometries of ATP synthesis of the otherwise‐grown cells were generally higher for the oxidation of glucose than for the oxidations of succinate and D‐lactate. Similar high P/O quotients were measured for the oxidations of glucose and ethanol in acetate plus ethanol‐grown cells.No significant energization could be observed during the oxidations of gluconate and acetate.The findings indicate that electrons delivered by the PQQ‐dependent glucose as well as by NAD+‐ dependent ethanol oxidations have probably a common place of entry into the respiratory chain. Glucose and NADH appeared to be energetically equivalent although at least two energetically different pathways might be involved in substrate oxidation.
Energy balance in solid state fermentation processes
Authors: Leön Rodriguez , Torres J. A. , Echevarrí J. , Saura G. 
Published: December 2004

AbstractIt was applied a macroscopic energy balance to a solid state fermentation process and an electron balance in order to estimate the temperature and the heat evolved in the process. There were employed several equations that describe the development of the system and offer the possibility to design or control such fermentations.
Introduction of the tac‐promoter by lactose under fermentation conditions
Authors: Neubauer P. , Wolff C. , Hecker M. , Hofmann K. , Meyer L. , Kruschke P. , Heinrich H. W. 
Published: December 2004

AbstractThe use of the expensive IPTG for induction of the tac‐promoter is not practicable at the industrial scale because of the large amounts necessary for induction. We developed a system in which IPTG as inducer was replaced by lactose which induces the tac‐promoter with the same efficiency. In E. coli CW3011 (pOF1.0) lactose is utilized as inducer and carbon source even in the presence of glucose, presumably as a consequence of the overproduction of lac‐permease.
Purification and characterization of chorismate mutase isoenzymes from ruta graveolens l.
Authors: Hertel S. C. , Hieke M. , Gröuger D. 
Published: December 2004

AbstractTwo isoenzymes of chorismate mutase (EC 5.4.99.5), designated as CM‐1 and CM‐2, were isolated and partially purified from suspension‐cultured cells of Ruta gravelens by DEAE‐sephacel chromatography and gel filtration. 60–72% of the total activity measured after DEAE‐sephacel chromatography were obtained as CM‐1 and 28–40% were CM‐2 activity. CM‐1 was inhibited by phenylalanine (K1 = 4 · 10−6 M) and tyrosine (K1 = 8. 10−6M) and activated by tryptophan. In contrast, CM‐2 was not influenced by these three amino acids. The molecular weights estimated by gel filtration on SEPHADEX G‐150 were 56000 for CM‐1 and 45000 for CM‐2, respectively. Both isoenzymes were stable at −20°C, but exhibited different behaviour during thermal inactivation and different optima of reaction temperature. CM‐1 catalysed the reaction at a pH optimum of pH 7.8 and CM‐2 showed a broad optimum between 6–10. The Km‐values for chorismic acid were determined to be 1.1 mM for CM‐1 and 0.5 mM for CM‐2. The isoenzymes showed different behaviour to inhibitors of sulfhydryl groups. There were no differences in all parameters of chorismate mutase examined for two various cell lines of Ruta graveolens.