bluuebunny/crossref_metadata_2025_split huggingface dataset:
Solid‐state (solid‐substrate) food/beverage fermentations involving fungi
Authors: Steinkraus K. H. 
Published: December 2004

Abstract“Solid‐substrate” fermentation developed in the Orient is a very useful fermentation method. It is presently used to produce a variety of foods, beverages and related products. Solid‐substrate fermentation products utilizing fungi including soy sauce, miso and tempe, ontjom, sake, and bread have been produced for centuries at the home and village level. They are examples of economical methods of preserving and improving the flavor, texture and nutritive values of cereal/legume substrates. “Solid‐substrate” fermentation is also applied to animal products such as milk to produce Roquefort and Camembert cheeses which diversify the food flavors available to man“Solid‐substrate”fermentation has certain advantages. The substrate is concentrated; the product can be extracted with relatively small quantities of solvent; the product can be easily dehydrated; moisture level can be controlled favoring the desired organisms; enzyme concentration is generally higher than is submerged fermentation; product concentration is generally higher than in submerged cultures; it is the only technique that yields true mushroom fruiting bodies and it can be used not only for production of crude enzyme concentrates (koji) but also for raising the protein content of high starch substrates. It also can be used to increase the content of vitamins at low cost. Disadvantages of “solid‐substrates”from the modern industrial processing view point are the greater difficulty of handling solid substrate and the greater difficulty of controlling the fermentation parameters, temperature, pH and oxygen, and rate of microbial growth compared with liquid submerged fermentations.
Submerged Cultivation of a Fungal Mutant Strain Humicola Lutea 120‐5 Producing Acid Proteinases
Authors: Aleksieva P. , Grigorov I. , Djerova A. , Sheremetska P. , Tchorbanov B. 
Published: December 2004

AbstractThe optimal parameters for the cultivation in 10‐l fermenters of a mutant strain Humicola lutea 120‐5 were established:temperature 30°C, inoculum size 6%, inoculum age 24 h, aeration rate 0,6 vol/vol · min, medium agitation 620 rpm and cultivation time 72 h. A maximal proteolytic activity of 2000 µg tyrosine liberated from 2%casein ml−1 culture filtrate min−1 at pH 3.0 and 40°C was obtained under the fixed conditions. α‐Amylase biosynthesis during the cultivation of H. lutea 120‐5 was observed but it was insignificant to the 72nd h. It is demonstrated that starch can be used as alternative to glucose carbon source. It is proved that the mutant strain H.lutea 120‐5 produced two acid proteinases.
Sorption of penicillium‐cellulase on cellulose and lignin
Authors: Shawky B. , Kasulke U. , Philipp B. , Schulz G. , Hirte W. 
Published: December 2004

AbstractSorption of Penicillium cellulase onto cotton linters samples differing in physical structure and onto KLASON‐ lignin from spruce has been investigated by determining cellobiase, CMCL‐ and ‘linters‐activity’ as well as protein content of a cellulase culture filtrate before and after contact with the sorbent at different temperature for different time intervals. CMCL‐ and cellobiase‐activity were found to be reduced much less by the sorption process onto the cellulose samples than ‘linters‐activity’ and protein content. Sorption increased in the order: untreated linters < mercerized linters < wet fibrillated (‘colloidal milled’) linters. With the KLASON‐lignin also a considerable sorption of the cellulase system was observed. Results are discussed with respect to preferential sorption of enzyme components.
Inhibierungserscheinungen bei der alkoholischen Gärung, I. Einfluß der Ethanolkonzentration auf die spezifische Ethanolbildungsgeschwindigkeit von Saccharomyces cerevisiae
Authors: Richter K. , Becker U. 
Published: December 2004

AbstractDifferential values of the specific ethanol production rate \documentclass{article}\pagestyle{empty}\begin{document}$$ v_{(t)} = \frac{1}{{x_{(t)} }} \cdot \frac{{dP}}{{dt}} $$ \end{document}
can be calculated exactly from experimental batch fermentation process data by use of a nonlinear regression programme. The method used is based on the fact, that the function P = f(t) can be approximated by an exponential equation. The specific ethanol production rate is calculated then from the first differential derivation of this equation using the appropriated values of actual biomass concentration. For two strains of Saccharomyces cerevisiae a linear and nonlinear kinetic pattern, respectively, was found for product formation. This result can be explained by a simple mathematical relation according to ν=ν0 − a . Pb,in which the exponent becomes 1 in the case of linear kinetic pattern.
Enhancement of enzymatic degradation of cellulose by application of mixed enzyme systems of different fungal origin
Authors: Szakäcs‐Dobozi M. , Szakäcs G. , Meyer D. , Klappach G. 
Published: December 2004

AbstractIndividual culture supernatants of six cellulolytic fungi and their mixed enzyme systems were compared in hydrolysis of pure celluloses and cellulose‐rich wastes. It has been observed that the hydrolysis rate of pure cellulosie substances in general increased by mixed enzymes as compared to the enzymes supernatant derived from only one microbial source. This effect was particularly high when Trichoderma and Penicillium enzyme systems were operated together.
Nucleic acid reduction from yeast activation of intracellular rnase
Authors: Bueno G. E. , Otero M. A. , Klibansky M. M. , Gonzäles A. C. 
Published: December 2004

AbstractThe study of a heat‐shock process for RNA reduction was carried out for different yeast strains. Different results were obtained from each of them. Candida utilis NRRL Y‐660 shows its best performance after a 8‐s. heat‐shock in the presence of 3% NaCl. For commercial baker's yeast Saccharomyces cerevisiae and Kluyveromyces fragilis L‐1930, similar results were obtained with only 1% of NaCl. The latter needed longer heat‐shock periods. e.g. 15s. to give such an RNA reduction. Biomass recovery ranged from 60 to 75%, being higher for C. utilis and K. fragilis while excessive losses were observed in S. cerevisiae cells.No significant protein deterioration was obtained in the best performance samples. The aminoacid profile appears to be improved in comparison to the starting material in these strains after RNA reduction.
Spektralphotometrische in‐situ‐Messungen der diffusen Reflexion bei der mikrobiellen Kohlenwasserstoffwandlung
Authors: Bayer C. , Iske U. , Glombitza F. , Nagel B. 
Published: December 2004

AbstractThe spectrophotometrical measurement of the diffuse reflectance in fermentation media has been proved useful for the analytical control of the microbial biosynthesis and transformation. A laboratory steril fermenter was fitted at an UV/VIS‐spectrophotometer equipped with a diffuse reflectance attachment. The apparent absorbance ΔE8(328) of aromatic hydrocarbons and the reciprocal scattering E8(650) have been compared with parameters of the discontinuous fermentation of the yeast Lodderomyces elongisporus and the bacteria strain EB 10c on petroleum hydrocarbons as a substrat.
The inhibitory effects of pyrocarbonic acid diethyl ester on lactobacillus casei and its phage Jl – A novel strategy for phage control in technical fermentation processes
Authors: Murata A. 
Published: December 2004

AbstractThe effects of pyrccarbonic acid diethyl ester (PADE) on Lactobacillus casei Sl and its phage Jl was investigated in relation to the control of phages in the dairy industry and other technica fermentation processes.PADE exhibited a bacteriostatic effect at 0.5 to 8 mM and a bactericidal effect at 10 mM or higher. It inhibited the growth of the phage at its bacteriostatic and bactericidal concentrations. The growth inhibition of the phage was reversible at the bacteriostatic concentrations but complete and irreversible at the bactericidal concentrations. PADE inactivated the free phage within several minutes; 10 and 30 mM of PADE inactivated 90 and 100%, respectively, of the phage. It completely decomposed into ineffective components in several minutes. The bacteria grew almost normally when they were inoculated after the complete decomposition of PADE.These four characteristics of PADE – its bactericidal effect, its inhibitory effect on phage growth, its phage‐inactivating effect and its decomposition – suggest a novel strategy for phage control in technical fermentation processes, including the dairy industry.
Wechselwirkungen zwischen Lektinen und Mikroorganismen II. Identifizierung von Mikrobiellen Stämmen und Mutanten durch die Kinetik induzierter Agglutinationen
Authors: Flemming Ch. , Sattler K. , Flemming I. 
Published: December 2004

AbstractThe kinetic of lectin or antibody induced agglutination between single cells in a complex but highly specific reproducible marker. It is useful for the identification of strains and mutants. Using the described method we are able to differentiate the mutants of yeast strains.
Wirkung von Ölen und fettsäuren auf Wachstum und Enzymbildung bei Thermoactinomyces vulgaris. VI. Studien zur Wirkungsweise von Öl
Authors: Leuchtenberger A. , Jakovleva M. B. , Ruttloff H. , Loginova L. G. 
Published: December 2004

AbstractSome aspects on the action of vegetable and animal oils and fatty acids on growth and protease synthesis of T. vulgaris were studied to interpret the stimulating effect of these substance. It was found that oil does not influence the hydrolysis of the substrate casein by the protease. However, the effect on the gas exchange during fermentation has a substantial importance. Furthermore, the metabolization of lipids shows that they play a role as carbon source.
Einfluß einiger Faktoren in Abhängigkeit von den Methoden bei der Immobilisierung eines bakteriellen Enzympräparats mit Milchkoagulationswirkung
Authors: Dobreva E. 
Published: December 2004

AbstractThe influence of different factors (binding time, pH, temperature, and enzyme/carrier ratio) on the efficiency of immobilization of enzyme preparation with milk clotting activity from Bacillus mesentericus M strain by use of different carriers and methods of binding was investigated. It has been established that the dependence of immobilization from pH is most pronounced and is mainly influenced by the nature of the carrier. The binding time is of essential importance only by immobilization through adsorption. The temperature has not any influence on the efficiency of immobilization of the indicate preparation. Saturation of many of the used carriers by the different methods for immobilization was achieved at enzyme/carrier ratio 1 : 10, with exception of the cases where glutaraldehyde was used as binding reagent. In this case then the ratio was 1 : 4.
Fluorimetrische und photometrische Schnellbestimmung von L‐Lysin in Fermentationslösungen
Authors: Hesse G. , W. Römer , Miosga N. , Wachtel E. 
Published: December 2004

AbstractIn a methodical paper two analytical‐chemical procedures are described which concern the control of L‐lysine formation during fermentation processes. On one hand lysine is determined fluorimetrically with o‐phthalaldehyde at defined pH, on the other spectrophotometrically with ninhydrine in acidic medium. The analytical conditions are discussed with respect to specifity, interferences, accuracy and reproducibility. A comparison of values with Autoanalyzer technique and two other methods for lysine determination offers the possibility to decide in what manner and with which aim of desired accuracy, economy and rapidity a given specimen has to be analyzed.
Effects of temperature on microbial ethanol production I. The temperature profile curve of ethanol production of the yeast strain saccharomyces cerevisiae Sc 5
Authors: Richter K. , Becker U. 
Published: December 2004

AbstractThe temperature‐profile curve of ethanol production of the yeast Saccharomyces cerevisiae Sc 5 is shown. Accordingly the biokinetic sphere of ethanol formation consists of 5 ranges. The maximum specific ethanol formation rate v0 is reached within the temperature limits of 32°C ≦ T ≦ 36°C, and the maximum temperature for ethanol formation amounts to T″max = 57°C. Within the first suboptimum temperature range ethanol formation is not retarded thermally. Using a modified ARRHENIUS equation the activation energy of ethanol formation was calculated to be ΔHÊtOH = (78.5 ± 2.2) kJ/mol.
Auswirkungen der Methode der Linearisierung des μ‐cs‐Verlaufs auf die Parameteranpassung bei dem Monodschen Modell
Authors: Stiebitz O. , Wolf K.‐H. , Klöden W. 
Published: December 2004

AbstractNowadays, the MONOD conception is the foundation for modelling the growth‐connected substrat consumption. The methods of the parameter estimation for μmax and Ks have a variable exactness. Using the experimental MONOD's data [1] variable graphical and numerical methods are analyzed from the point of statistical view. Appropriate objective functions are proposed.
Dynamics, regulation, block description and optimal performance of cellular metabolism in open conditions: Outline of a unifying concept
Authors: Reich J. G. 
Published: December 2004

AbstractThe paper offers a survey of theoretical concepts for the analysis of metabolic systems in open connditions such as realized in cultures of microbial cells. The dynamics and regulation of metabolism within the cell is condensed into a block description of the system to which global performance and design criteria are applied.
Einflußder Aufbewahrungsmethode auf die Stabilität der biotechnologischen Eigenschaften von Zellulose utilisierenden Pilzen
Authors: Hornecka D. , Czajkowska D. , Ilnicka‐Olejniczak O. 
Published: December 2004

AbstractThe influence of long‐term storage on the stability of the cellulolytic enzyme and protein biosynthesis ability, was determined.Microorganisms belonging to genera Aspergillus, Fusarium, Penicillium, Sporotrichum, Allescheria and Mucor were used. The strains were stored on wort agar slants, on SAUNDER'Smedium and on a medium according to MANDELS‐WEBER, under paraffin oil or without it. After 3 years storage no influence of the storage method on the biosynthesis of cellulolytic enzymes (strain A. niger 33/2 and 33/20) was found. A systematic increase in the celluloslytic activity was exhibited by strains A.n. 33/2 and A.n. 33/20 on wort agar (40 and 98%, respectively) and on SAUNDER'Smedium (79 and 66%, respectively), as well as by the new strain CEL 2 on Saunder's medium without paraffin oil.
A fed‐batch cultivation method for the simultaneous utilization of glucose and formate by yeasts
Authors: Müller R. H. , Zimmermann E. , Babel W. 
Published: December 2004

AbstractA fed‐batch cultivation method was elaborated which 1. warrants simultaneous consumption of glucose and formate, 2. is easy to employ and provides reproducible results, 3. gives information about the role of formate in yeast growth, 4. results in almost identical conditions for parallel cultures on glucose and glucose/formate. The method was applied to Hansenula polymorpha and Saccharomyces cerevisiae. Relevant results were obtained and were comparable to those found previously under chemostatic conditions. Thus, the method is considered suitable for comparative investigations of yeast growth on glucose/formate to demonstrate the role of formate as an additional energy donor.
Rapid determination of L‐lysine with an enzyme electrode by steady state and kinetic measurement
Authors: Weissbach F. , Kreibich G. , Bartels K. , Schülke W. 
Published: December 2004

AbstractFast and simple methods of determination of L‐lysine by a potentiometric enzyme electrode based on a CO2 electrode and L‐lysine decarboxylase are described. Measuring devices for manual and automated operation for steady state response measurement as well as kinetic measurement are compared. Sample frequency may be increased by decreasing the time of a measuring cycle.
Hopf bifurcation for a family of two‐state microbial growth models
Authors: Bley Th. , Wegner B. 
Published: December 2004

AbstractWe describe a family of two‐state microbial growth models, in which growth and maintenance are assigned to two different cell states. The way of splitting periodic solutions for low dilution rates of a continuous fermentation is shown. The existence of these periodie solutions is mainly influenced by the properties of substrate consumption, which the maintenance rate in the second cell state amounts to.
Production of cellulases and xylanase by Trichoderma reesei F‐522 on pretreated wheat straw
Authors: Szczodrak J. 
Published: December 2004

AbstractAutohydrolyzed and ethanol‐alkali pulped wheat straw was examined as a candidate feedstock for both cellulase and xylanase production and enzymatic hydrolysis. Submerged cultures of Trichoderma reesei F‐522 grown on hydrothermally modified straw provided culture supernatants of the highest enzymatic activities, whereas the maximal efficiency of enzymatic hydrolysis was recorded in straw treated with ethanol‐NaOH mixture. Some culture conditions were optimized to improve the growth and cellulase production by T. reesei on autohydrolyzed wheat straw.
Purification and properties of two β‐glucosidases isolated from Aspergillus niger
Authors: Witte K. , Wartenberg A. 
Published: December 2004

AbstractThe cellulase complex of the fungus Aspergillus niger (strain CBS 554.65 = ATCC 16 888) was fractionated by gel filtration yielding six pronounced peaks. Only proteins from the fraction corresponding to the first peak (96 kDa) showed β‐glucosidase activity vs. the substrate 4‐nitrophenyl‐β‐D‐glucopyranoside (pNPG). These proteins have been fractionated by chromatofocusing, yielding two β‐glucosidases (I and II) which are shown to be homogeneous in isoelectric focusing experiments (pI = 4.6 and 3.8, respectively). Kinetic experiments with pNPG, MU‐glucopyranoside and cellobiose revealed that both types of β‐glucosidases behave like aryl‐β‐glucosidases. β‐Glucosidase‐I acting on pNPG exhibits a split kinetics characterized by high and low substrateconcentration kinetics which are differentiated by different values of V and of Km. In addition, β‐glucosidase‐II is shown to be an exo‐glucohydrolase as deduced from experiments with MU‐cellobiopyranoside.Experimental features should be emphasized; usual soft‐gel ion‐exchange materials did not work in the chromatofocusing separation of the two β‐glucosidases, in contrast to the 10μ‐Si 500 = DEAE exchange material (Serva) typically used in HPLC‐experiments. Furthermore, protein content determinations based on different procedures yielded widely differing values.
Controlled porous glass (CPG) with reactive epoxy groups as support for affinity chromatography I. Optimization of CPG modification and the binding of glucose with modified surface
Authors: Rogalski J. , Dawidowicz A. L. 
Published: December 2004

AbstractThe selective and complementary interaction between the ligand bound to support surface and isolated substance is the key of the affinity chromatography. This is the reason of the research in the field of certain sorbents. They are obtained by chemical reaction of matrix with proper ligands. It is carried out mainly by using bifunctional substances which make the reaction with the ligand in question possible. This paper deals with the preparation of controlled porosity glass with reactive epoxy groups. In order to obtain such support and avoid application of a proper epoxy silane compound, the double‐step reaction using simple agents was employed. The sorbent syntheses were optimized. The prepared sorbents were applied for coupling some carbohydrates and amino acids.
Energetic efficiency of complex substrate utilization by trichoderma viride
Authors: Leite M. , Apine A. , Zeltina M. , Shvinka J. 
Published: December 2004

AbstractThe efficiency of carbon substrate utilization is evaluated as the thermodynamic efficiency (ηx) of microbial growth.Three methods based on mass‐energy balance are used for the efficiency studies of complex substrates (straw, plant juices, lye) utilization by microfungi Trichoderma viride.

According to substrate and biomass balance ηx = 0.55, 0.37 and 0.36 for Trichoderma viride growth on alkali pretreated wheat straw during 23, 34 and 50 hours. Cellulose biodegradation increases with cultivation time. However, the efficiency of cellulose utilization for cell mass growth decreases at the same time.
In accordance with oxygen‐balance calculations ηx = 0.75 and 0.71 for the same processes. The discrepancy in results from the above two methods probably can be explained by the following:

Substrate and biomass balance gives underestimated results.
Oxygen balance method includes the part of energy for extracellular product formation and therefore ηx can be overestimated.
The efficiency of complex soluble substrate utilization (lye, green juice, deproteinized brown plant juice) tested by means of pulse method gives the values of ηx = 0.72 – 0.88. Similar high estimates of ηx in C‐limited batch culture are observed for soluble carbohydrates (glucose, galactose, lactose, xylose) but not for acetate. The pulse method is advantageous for testing the “true” efficiency of carbon substrate utilization in a definite physiological environment.
Degradation of L‐arabonate by extracts of different filamentous fungi
Authors: Elshafei A. M. 
Published: December 2004

AbstractTen Aspergilli and Penicillia were tested for the capabilities of their extracts in degrading L‐arabinose or L‐arabonate nonphosphorolytically. L‐arabonate dehydratase was nearly absent, while the reverse reaction of 2‐keto‐3‐deoxy‐L‐arabonate (KDA) aldolase was operative in extracts of all the tested organisms grown on L‐arabinose or L‐arabonate as the sole carbon source. Degradation of different related substrates by cell‐free extracts of Aspergillus ustus showed that L‐arabonate, D‐gluconate, D‐galactonate and D‐galactonic acid‐γ‐lactone were degraded under these conditions. Chromatographic studies identified the L‐arabonate degrading products of such degradation in A. ustus as KDA (traces), pyruvic acid and α‐ketoglutaric acid.
Degradation of some sugars and sugar acids by the nonphosphorylated D‐gluconate pathway in Aspergillus ustus
Authors: Elshafei A. M. 
Published: December 2004

AbstractThe degradation of fifteen sugars, sugar acids and related substrates were examined using cellfree extracts of Aspergillus ustus growing on D‐glucose, D‐mannose, D‐galactose or D‐gluconate as the only carbon source. D‐gluconate was superior for the induction of the enzymes capable for the degradation of some of these substrates. The addition of 0.5% malt extract with D‐gluconate to the growth medium or the presence of shaking conditions resulted to an increase in the degradation of those substrates, whileas the incorporation of 0.5% malt extract alone to the medium has no effect. Extracts of D‐gluconate‐grown mycelia of A. ustus degraded D‐gluconate > D‐galactonate > 1 : 5 gluconolactone and > L‐arabonate nonphosphorolytically more effectively. Optimum pH and temperature for the degradation of D‐gluconate were found to be 8.0 and 40°C, respectively. Thermal stability studies on the behaviour of D‐gluconate dehydratase showed that this enzyme was stable at 50°C and 60°C for 30 and 5 minutes, respectively. Specific activity of this enzyme was increased three times when cell‐free extracts were incubated at 60°C for 5 minutes. MgCl2 and CoSO4 were good activators, while CaCl2 p‐mercurychlorobenzoate (PMCB), sodium arsenite, ZnSO4, CuSO4, iodoacetic acid, MnCl2 and FeSO4 were potent inhibitors for D‐gluconate dehydratase activity. Km was calculated for D‐gluconate and found to be 2.5 × 10−2 M.