bluuebunny/crossref_metadata_2025_split huggingface dataset:
Continuous chemical sterilization of microbiological media with β‐propiolactone
Authors: Toplin Irving 
Published: December 2004

AbstractA laboratory bench set‐up for the continuous chemical sterilization of microbiological media using β‐propiolactone was developed. The apparatus permits the sterilization of up to 4 liters/hr. of liquid media. The parameters of hydrolyzing time and temperature necessary to reduce the β‐propiolactone to nontoxic levels were determined using a E. coli‐nutrient broth system. The sterilization technique was applied successfully to a variety of media, and its potential usefulness on an industrial scale is discussed.
Automatic control of dissolved oxygen levels in fermentations
Authors: Siegell Stuart D. , Gaden Elmer L. 
Published: December 2004

AbstractDissolved oxygen levels in fermentation systems are affected by (a) gas flow rate, (b) degree of agitation, and (c) oxygen partial pressure in the gas. Since the first two variables cannot easily be separated, a method for dissolved oxygen control has been devised based on the variation of oxygen partial pressure in the gas. Oxygen and nitrogen are fed to a special mixing valve capable of varying the proportions of the two gases while keeping the total flow rate constant. A dissolved oxygen electrode and control system adjust the valve setting to automatically maintain a preset oxygen level. Oxygen analyzers, monitoring the inlet and outlet gas streams, provide additional information from which oxygen absorption and uptake rates may be determined. The system provides a means for the quantitative and independent study of aeration and agitation effects. In addition, it offers a basis for routine control of oxygen levels in plant fermentation equipment.
Stripping in sparged fermentation systems. II. The effect of operating temperature and gas phase pre‐humidification in an ethanol‐water system
Authors: Hamer G. 
Published: December 2004

AbstractThe effect of operating temperature upon relative stripping of a two component (ethanol–water) mixture by dry air, with the aid of a previously derived equation,1 is considered. The variations encountered in the relative humidity of air sparged to fermentors are discussed. A general equation is developed for the stripping of a more volatile component from a solution in water by wet air. The theoretical results derived from this equation are tested experimentally at one particular level of prehumidity of the air sparged to an ethanol–water system.
Kinetic studies of gluconic acid fermentations
Authors: Humphrey Arthur E. , Reilly Peter J. 
Published: December 2004

AbstractThe kinetics of the gluconic acid fermentation have been studied at pH 5.8 Pseudomonas ovalis B‐1486 was used as the fermenting organism. D‐Gluconolactone was found as an intermediate in the fermentation and accumulated at times in large amounts. When this occurred, hydrolysis of the lactone was found to be the rate limiting reaction. This can be, under certain conditions, a poor fermentation in which to study oxygen transfer limiting conditions. Further, it is impossible to relate batch and continuous kinetic data for this fermentation unless the lactone hydrolysis reaction is taken into account.
Submerged production of arginine decarboxy‐oxidase in 20‐liter and 200‐liter fermentors
Authors: Delcambe L. , Pho Dang Ba , Regnouf F. , Olomucki A. 
Published: December 2004

AbstractA process has been developed whereby arginine decarboxy‐oxidase (ADO) can be produced by growing Streptomyces griseus in submerged form in 20‐l. and 200‐l. tank fermentors. A medium containing salts, corn steep, glucose, or starch is used. With addition of 0.02% arginine and with limited aeration, a high yield has been obtained.
Location and action of Streptomyces griseus α‐D‐mannosidase, an antibiotic‐transforming enzyme
Authors: Inamine Edward , Demain Arnold L. 
Published: December 2004

AbstractStreptomyces mannosidase, like the enzyme from other sources, is shown to require a divalent cation for enzyme activity. N‐Ethylmaleimide pretreatment of enzyme‐containing cells eliminated the requirement of aeration for enzyme activity. Methyl‐α‐D‐mannoside was found to be a strong inhibitor of the hydrolysis of both p‐nitrophenyl‐α‐D‐mannoside and mannosidost reptomycin. The enzyme is bound at or near the surface of the cell and is inactivated by sonic oscillation. Small participate matter containing most of the activity can be released from the cells into water, such release being inhibited by phosphate, Tris, or sodium chloride.
Proteases of the genus Bacillus. II. Alkaline proteases
Authors: Keay Leonard , Moser Patricia W. , Wildi Bernard S. 
Published: December 2004

AbstractThe alkaline proteases of B. subtilis NRRL B3411, B. pumilis, and B. licheniformis have been isolated by fractionation followed by ion exchange chromatography and their homogeneity demonstrated. General enzyme properties of the B. sublitis NRRL B3411 alkaline protease have been studied and attempts made to differentiate a group of alkaline proteases. It is clear that the alkaline proteases known as Subtilisins or Subtilopeptidases are not, exclusive to B. subtilis but are common to many Bacilli and therefore the generic name Bacillopeptidases has been proposed. It is clear too that on the basis of the effect of pH on activity, amino acid composition, esterase activity, and immunological cross‐reactions the Bacillopeptidases can be divided into two groups or types: (a) Bacillopcptidase A (Subtilisin A or Subtilopeptidase A) which includes Subtilisin Carlsberg, B. licheniformis, and B. pumilis alkaline proteases; (b) Bacillopeptidase B (Subtilisin B or Subtilopeptidase B) which includes B subtilis NRRL B3411, Subtilisin Novo, Subtilisin BPN' (Nagarse), alkaline protease Daiwa Kasei, and (probably) B. subtilis var. amylosacchariticus. At present, no further differentiation is possible and whether or not the enzymes within group A or B are identical remains an open question. Methods for examination of crude enzyme mixtures or fermentation beers are described and from the examination of a number of crude enzymes and fermentation beers it appears that organisms producing Bacillopeptidase A do not produce neutral protease or amylase, while organisms producing Bacillopeptidase B produce a neutral protease and amylase as well.
Kinetics of the conversion of glucose to gluconic acid by Pseudomonas ovalis
Authors: Bull Daniel Newell , Kempe Lloyd L. 
Published: December 2004

AbstractThe concept of a “critical oxygen concentration” is conventionally considered to hold for the submerged aerobic fermentation of glucose to gluconic acid. Above the critical level the fermentation rate is supposedly independent of oxygen concentration. In this work it is shown that, at a given agitation rate, the fermentation is independent of dissolved oxygen when above the critical. However, an increase in the agitation rate results in an increase in the fermentation rate. This increase was shown to be accompanied by an increase in the gluconolactone concentration in the broth. Gluconolactone, an intermediate in the reaction pathway, is hydrolyzed nonenzymatically to gluconic acid. Evidence is presented to suggest that the increased gas‐liquid interfacial area brought about by increased agitation causes an increased net rate of lactone formation. This in turn results in an increased rate of hydrolysis of the lactone to gluconic acid. A model is presented hypothesizing that negatively charged cells adsorb at the gas‐liquid interface. These cells attract hydrogen ions, causing a lowering of the pH in the film around the bubbles. It is this lowered pH which is considered to bring about increased fermentation rates when the interfacial area is increased. Supporting evidence is presented.
Microbiological leaching of a zinc sulfide concentrate
Authors: Torma A. E. , Walden C. C. , Branion R. M. R. 
Published: December 2004

AbstractThe microbiological extraction of zinc from a high‐grade zinc sulfide concentrate has been investigated, using a pure strain of Thiobacillus ferrooxidans. Conditions such as temperature, pH, pulp density, nutrient, concentration, and specific surface of solids have been studied in terms of their effects on zinc extraction rate and in some instances on final zinc concentration in solution. Where appropriate, optimum conditions for leaching have been specified.
Utilization of bound lactase in clinical chemistry
Authors: Stasiw R. O. , Patel A. B. , Brown H. D. 
Published: December 2004

AbstractA “stick test” for the detection of lactose has been developed based upon the enzyme lactase chemically bound via Procion brilliant orange to DEAE‐cellulose. Utilization of the bound rather than the free enzyme allows an ease in its addition to and removal from the reaction medium as well as a facile control of reagent quality and quantity. The bound enzyme “stick” may be reused for several determinations.
Continuous production of extracellular protease by Bacillus subtilis in a two‐stage fermentor
Authors: Jensen Donald E. 
Published: December 2004

AbstractGrowth and protease production of Bacillus subtilis in semisynthetic and synthetic media were studied in batch culture and in a two‐stage, laboratory scale, continuous fermentor. The amount, of extracellular protease production was measured under specific growth conditions in both stages of the ferment or. At the dilution rates employed, the cells in the first stage of the ferment or produced negligible quantities of protease, and the culture primarily functioned as a continuous inoculum for the second stage of the fermentor. The culture effluent from the second stage of the fermentor contained extracellular protease, on the average, equal to 60 per cent, of the activity that had been found in the supernatant of a 48‐hr batch culture grown in a medium having the same composition as that in the continuous fermentor. Extracellular protease was produced in semisynthetic medium by B. subtilis in the two‐stage fermentor for as long as 20 days without culture degeneration. Additional studies indicated that continuous protease production could also be achieved in a synthetic medium. The RNA/ protein ratios of cells grown in semisynthetic medium in batch culture and in each stage of the two‐stage fermentor were examined. There was a positive correlation between the amount of protease produced by the cells and their RNA/ protein ratio. Techniques employed for continuous production of protease by B. subtilis and the potential use of the method for investigating the control of secondary metabolite synthesis are discussed.
Preparation and characteristics of microcapsules containing asparaginase
Authors: Mori Takao , Sato Tadashi , Matuo Yuhsi , Tosa Tetsuya , Chibata Ichiro 
Published: December 2004

AbstractConditions for the preparation of microcapsules containing asparaginase by interfacial polymerization were investigated.The activity of microcapsules prepared under the optimal conditions was about 37% compared with that of native asparaginase. Particle size of microcapsules could be controlled by determining the stirring rate and concentration of Span 85. The membranes of microcapsules were resistant to mechanical shock or attack of chymotrypsin, and no leakage of asparaginase from microcapsules was observed.
The “rotary column” method for growth of large‐scale quantities of cell monolayers
Authors: Santero Giovanni G. 
Published: December 2004

AbstractA method and an apparatus that reduce the heavy expenses involved in traditional methods for the large‐scale monolayer production of primary and secondary, strain and line cells and of the biologicals derived therefrom are described. The method is based on the principle of gathering in a single unit a sheaf of columns by means of general manifolds fitted with cocks. The growth of cells on the glass walls is irrespective of the number, length, and diameter of the columns used. The apparatus, placed in a thermo‐adjustable room and connected to adequate devices which allow it to rotate on its longitudinal axis and to be set in a vertical position, need not be dismounted nor transported since it can be connected by a number of tubes to the necessary services. Sterilization is carried out by flowing steam and fluids are poured in or drained off by vacuum or pressure. A microscope fitted to the bearing structure allows the operator to observe the cell monolayers and the cytopathic effect of viruses on the whole length of the outer columns. During the various working stages pH is under continuous control and automatically adjusted. The whole working cycle is extensively described (cleaning, sterilization, seeding, incubation, trypsinization of the monolayer, culture and harvesting of the virus) and results compared with those obtained by traditional methods.
Mannose‐containing polysaccharides of yeasts
Authors: Spencer J. F. T. , Gorin P. A. J. 
Published: December 2004

AbstractThe known species of yeasts produce at lest 180 different polysaccharides having mannose as a major constituent. The type of mannan formed is characteristic of the yeast species, and can be used as an aid in identification and classification. The immunological characteristics of yeasts depend largely upon the nature of the mannans. Some of the yeast mannans can be produced in relatively high yields, and have been suggested as replacements for plant and bacterial gums as thickeners, dispersing agents, and similar applications. However, more significant uses, based on the finer differences in their chemical structures and the specific reactions they undergo, may result from a closer study of these polymers.
The relationship of substrate, growth rate, and maintenance coefficient to single cell protein production
Authors: Abbott Bernard J. , Clamen Allen 
Published: December 2004

AbstractVarious organic compounds were assessed as potential substrates for single cell protein production. Substrate evaluation was based on the costs associated with the substrate, oxygen, and heat yield coefficients: Ysub, Yo, and Ykcal, respectively. Yo, and Ykcal, were calculated from experimental values of Ysub, and from the elemental composition of bacterial cells. The dependence of the yield coefficients on the specific growth rate (μ) and maintenance coefficient (m) also was assessed. The analysis disclosed that m caused two‐ to threefold variations in the yield coefficients as μ was increased from 10% to 100% of μmax. The effect of different m values at constant specific growth rates also was determined. The value of m had a significant effect on the yield coefficients even at high specific growth rates. Assignment of cost factors to the yield coefficients provided an estimation of the impact m and μ on biomass production costs.
Kinetic analysis of diauxic growth and pectolytic enzyme formation in aspergilli
Authors: Zeteliaki‐Horvåth Kornélia , Békåssy‐Molnår Erika 
Published: December 2004

AbstractKinetic studies on the growth of Aspergillus strains as well as constitutive and inductive polygalacturonase formation have been made in bath fermentations, without pH control. Equations describing growth and product formation of the four‐stage growth of microorganisms were applied for the first time to diauxic growth and enzyme formation of Aspergillus strains. Diauxic growth of the cultures has been found in both sucrose‐ and peetin‐containing media. Enzyme concentration in the second transient phase, calculated by the use of new equations, proved to be negligible. In the exponential and declining phases, the calculated values of mycelial and enzyme concentrations were in good agreement with the values observed. Types of classification of the product formation of Luedeking and Piret refer to the second cycle of diauxie. The types of product formation described by Kono and Asai and Luedeking and Piret are mostly in good agreement with each other. The greatest difference has been found in the case of inductive endo‐polygalacturonase formation, where the final enzyme formation could not be plotted because of the decrease (autolysis) in mycelial weight.
Maturity and product formation in cultures of microorganisms
Authors: Brown D. E. , Vass R. C. 
Published: December 2004

AbstractThe concept of a maturation time (tm) for a product formation by a microbial culture is developed and a simple method is described for determining this parameter and also the product formation rate constant (kp) from batch culture experiments. The concept has been utilized in a general model for the prediction of steady state product concentrations in single‐stage continuous‐flow culture systems.
Hydrolysis of β‐galactosides using polymer‐entrapped lactase. A study towards producing lactose‐free milk
Authors: Dahlqvist Arne , Mattiasson Bo , Mosbach Klaus 
Published: December 2004

AbstractA yeast lactase, Maxilact, was immobilized in crosslinked polyacrylamide using a bead‐polymerization technique. The polymer beads obtained, containing the entrapped enzyme, were used for the preparation of lactose‐free milk. The binding yield of the enzyme and residual enzymic activity in the “enzyme beads” were studied as a function of the amounts of monomeric acrylamide and cysteine and bovine serum albumin present as protecting agents in the monomer‐enzyme solution prior to polymerization. A maximum of about 75% of the enzyme could be immobilized using a 20% (w/v) solution of acrylamide plus N, N′‐methylenebis‐acrylamide, whereas the highest activity quotient (bound to free) of about 60% was observed on using a 25% solution. The presence of cysteine increased the activity by up to 30% and that of serum albumin up to about 15%.
Dextranase production from Penicillium funiculosum
Authors: Kosaric N. , Yu K. , Zajic J. E. , Rozanis J. 
Published: December 2004

AbstractTwenty‐eight Penicillium cultures were screened for dextranase activity. Dextranase yield of about 2000 DU/ml was obtained with Penicillium funiculosum SH‐5. Maximum dextranase concentration was attained only when cell mass decreased. The kinetics of the dextranase production was correlated with the cell mass by a two‐parameter model. The optimum pH and temperature for dextranase were 5.0‐5.5 and 55°C, respectively. Crude dextranase preparation was inhibitory to insoluble glucan formation by streptococcus mutans 6715 in vitro.
The kinetics of yeast growth on pure hydrocarbons
Authors: Blanch H. W. , Einsele A. 
Published: December 2004

AbstractThe kinetics of C. tropicalis growth were investigated with pure n‐hexadecane as dispersed phase substrate. Two distinct growth phases were found: In the first phase, exponential growth was independent of stirrer speed. The onset of the second phase, one of linear growth, was determined by stirrer speed. By the use of two different fermenter types, it was shown that the drop size of the dispersed phase was not primarily responsible for the observed kinetics. It was considered that the formation of biological flocs determined the observed growth pattern. This was substantiated by the results of continuous cultures in the different fermenter types, with various substrate concentrations.
Glutamic acid production with gel‐entrapped Corynebacterium glutamicum
Authors: Slowinski Wlodzimierz , Charm Stanley E. 
Published: December 2004

AbstractA glutamic acid producing microorganism (Corynebacterium glutamicum) is entrapped in a polyacrylamide gel. These immobilized microorganisms were used to produce glutamic acid in successive batches of fresh medium. Free microorganisms similarly used produced much less glutamic acid under similar conditions.
Effect of aeration intensity on the biochemical composition of baker's yeast. I. Factors affecting the type of metabolism
Authors: Oura Erkki 
Published: December 2004

AbstractEfforts were made to eliminate the influence of other factors as far as possible in order to obtain reliable results on the effects of oxygen on the growth of baker's yeast. A cultivation method is presented which permits the study of the effects of aeration intensity under conditions where the influence of catabolite repression is eliminated. A completely synthetic medium with glucose as the only carbon and energy source is also described.The capacity of yeast to perform aerobic metabolism varies when cultivated under different intensities of aeration. A clear maximum is observed for growth with 10% oxygen in the aerating gas mixture. Under conditions where catabolite repression does not function yeast has the potential for oxidative metabolism even under oxygen‐limited growth. The main agent controlling the ability of yeast to support growth using only the oxidative metabolism is the available oxygen.At high oxygen tensions the metabolism is disturbed.
The tubular loop batch fermentor: Basic concepts
Authors: Russell T. W. F. , Dunn I. J. , Blanch H. W. 
Published: December 2004

AbstractA tubular loop batch fermentor has been designed and constructed, and was found to behave in a similar manner to a conventional stirred tank reactor. It appeared that foaming could be greatly reduced as no air ever encountered the impeller. The fluid mechanics of pipe flow are considerably simpler than tank flow patterns. On this basis a design procedure for a large scale tubular fermentor was outlined, which had considerable advantages over the more complex scale‐up problems of a tank fermentor.
Preparation of immobilized enzymes from acrylic monomers under γ‐ray irradiation
Authors: Maeda H. , Suzuki H. , Yamauchi A. , Sakimae A. 
Published: December 2004

AbstractImmobilized glucoamylase, invertase, and β‐galactosidase were prepared by using 2‐hydroxyethyl acrylate and dimethylacrylamide under γ‐ray irradiation. In the case of 2‐hydroxyethyl acrylate, the monomer‐enzyme solution was changed to the gel by irradiation of less than 1.0 Mrad, but it was difficult to eliminate enzyme leakage from the gel. When leakage was eliminated by increased irradiation, the activities of the gels were very low. In the case of dimethylacrylamide, the monomer–enzyme solution was changed to a gel by irradiation of 1.0 Mrad; leakage could be eliminated by irradiation of 2.0 Mrad. This gel possessed very high activity. In the case of acrylic acid‐sodium acrylate, the monomer–enzyme solution could not be changed to a gel. In preparing gels, high concentrations of enzyme protein had a tendency to obstruct gelation.
High productivity tank fermentation for gramicidin S synthetases
Authors: Tzeng Chu H. , Thrasher Kathleen D. , Montgomery John P. , Hamilton Bruce K. , Wang Daniel I. C. 
Published: December 2004

AbstractA high productivity tank fermentation for gramicidin S synthetases has been developed to supply biocatalyst for a preparative‐scale ATP‐driven cell‐free enzymatic synthesis employing the polypeptide antibiotic, gramicidin S, as a model product. A rich, complex medium supports rapid and dense growth of the enzyme‐producing microorganism, Bacillus brevis ATCC 9999, accompanied by the appearance of excellentenzyme activities. Under conditions used, the two enzyme fractions of the gramicidin S synthesizing system, as well as the total enzymatic activity for synthesis of gramicidin S, all reach their maxima simultaneously at the point where growth enters the stationary phase. Successful batch enzyme fermentations have been performed at the bench (14 liter) and pilot (180 liter)scales.
Conversion of L‐sorbose to L‐sorbosone by Gluconobacter melanogenus
Authors: Kitamura I. , Perlman D. 
Published: December 2004

AbstractGrowing cultures, washed cells, and cell‐free extracts of Gluconobacter melanogenus IFO 3293 were found to convert L‐sorbose to L‐sorbosone. The product was identified by thin layer chromatography of the 2, 4‐dinitrophenylhydrazone, and by paper partition chromatography using chemically prepared materials as standards. Factors influencing the conversion included incubation temperature and composition of the growth medium. Addition of betaine or choline to the growing cultures stimulated conversion of L‐sorbose to L‐sorbosone.