bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of the Intracellular Amino Acid Pool and Proteins from Whole Cells of Rhizobium japonicum
Authors: Lillich T. T. , Elkan G. H. 
Published: March 2008

ABSTRACT.The amino acid composition of proteins from whole cells of Rhizobium japonicum was determined. The proteins contain only those amino acids commonly associated with bacteria and in ratios approximately equal to those which have been reported in other bacterial genera. Analysis of the intracellular amino acid pool showed relatively large amounts of alanine, glutamate and lysine. These amino acids are normally associated with the peptidoglycan layer of bacterial cell walls leading to speculation that the pool observed was for the synthesis of cell wall precursors rather than for general protein synthesis. The high levels of alanine relative to the other amino acids can also be explained by the operation of alanine dehydrogenase, (E.C. 1.4.1.1) which is an assiniilatory enzyme for ammonia.
A Selective Medium for Enumerating Salt Requiring Vibrio spp. from Wiltshire Bacon and Curing Brines
Authors: Gardner G. A. 
Published: March 2008

ABSTRACT.A medium is described for the enumeration of salt requiring Vibrio spp. which are found commonly in the microflora of spoiled bacon. Data are presented on the selectivity of the medium in the examination of Wiltshire style bacon and curing brines.
The Influence of Temperature and Moisture on the Disinfecting Activity of Methyl Bromide on Infected Poultry Litter
Authors: Harry E. G. , Brown W. Burns , Goodship Gwen 
Published: March 2008

ABSTRACT.At 25°, exposure of finely sieved poultry house litter for 20 h to methyl bromide (MeBr) gas at concentrations of 10–120 mg/l, i.e. concentration‐time (CT) products of 200–2400 mg h/l, resulted in a marked reduction in the number of bacteria present in terms of Salmonella typhimurium, Escherichia coli and micrococci. The activity of the gas was affected adversely by a reduction in temperature and by its application to litter of a high moisture content. Except with wet litter, a reduction of >99% of the Salm. typhimurium present resulted from exposure at 25° to gas concentrations as low as 10 mg/l (CT product, 200 mg h/l) and it was undetected in samples exposed to 40 mg/l at 25° (CT product, 800 mg h/l) or 80 mg/l at 10° (CT product, 1600 mg h/l). The significance of reductions of this order, in terms of the infectivity of the litter to chicks subsequently reared on it, is discussed. Escherichia Coli showed a susceptibility similar to that of Salm. typhimurium but micrococci were considerably more resistant.
Inhibition of Aflatoxin Accumulation in Smoked Substrates
Authors: ARSECULERATNE S. N. , SAMARAJEEWA U. , WELIANGA L. V. 
Published: March 2008

The pattern of fungal colonization on processed (smoked) copra kernels and the levels of aflatoxin detected in copra and in culture of Aspergillus flavus on fresh coconut suggested that aflatoxin accumulation was inhibited by the smoking process. This paper describes the study of the smoking process under laboratory conditions with fresh coconut and potato dextrose broth; aflatoxin accumulation was found to be significantly or totally inhibited in both smoked coconut and in smoked broth. Mycelial growth was inhibited to a lesser degree.On account of the urgent need for simple, cheap and efficent techniques for the processing and safe storage of food substrates especially in poor tropical countries, we suggest that the smoking process deserves study under industrial conditions for the protection of other agricultural food crops (e.g. groundnut) as well.
Large‐scale Harvesting and Concentration of Bacteria by Tangential Flow Filtration
Authors: REID D. E. , ADLAM C. 
Published: March 2008

A self‐contained tangential flow filtration system was used to harvest, concentrate and wash suspensions of corynebacteria aseptically.
Using two filter stacks each containing 15 × 0.6 nm filters, 60 l of culture could be concentrated to 8 l, thrice washed and harvested within a working day.
Organism washing was efficient and no impairment of activity of harvested organisms was seen.
Tangential flow filtration provides a simple rapid method for harvesting bacteria and their extracellular products aseptically from cultures grown on a production scale.
An Automatic Apparatus for the Evacuation and Filling of Several Anaerobic Jars Simultaneously
Authors: IMPEY C. S. , PRESCOTT E. H. A. 
Published: March 2008

An apparatus is described that will automatically evacuate and refill with gas up to four standard anaerobic jars, simultaneously.
The control valves can be switched manually when large anaerobic vessels, such as modified milk churns are in use.
Evaluation of Media for Counting Viable Bacteria in Estuaries
Authors: GOULDER R. 
Published: March 2008

Plate counts of viable bacteria in estuarine water samples were made using seven standard agar media.
Highest counts were obtained on Anderson's medium which is therefore recommended for general estuarine use.
The composition of Anderson's medium was peptone 2.5 g, yeast extract 2.5 g, FePO4 0.1 g and agar 15.0 g, made up to 11 with artificial estuary water.
SHORT COMMUNICATIONAn Adaptable System for Timed Aseptic Sampling and Storage of Microbial Cultures
Authors: NEWMAN P. B. 
Published: March 2008

Equipment is described which permits aseptic sampling of microbial cultures and the subsequent controlled temperature storage of these samples.
The system is fully automated, has a flexible sampling programme (10 min—2 days’interval between samples) and a capacity of up to 300 × 15 ml samples.
It is inexpensive to construct and sufficiently flexible to permit direct integration with standard monitoring and/or automated analytical systems.
Microbial Ethanol, Yeasts and Coliform Bacteria in the Stomachs of Milk Fed Calves
Authors: WHITE R. W. 
Published: March 2008

The frequent occurrence of Torulopsis glabrata in calf rumen is confirmed.
The presence of this organism is not necessarily accompanied by ethanol production.
Ethanol is frequently found in the rumen of calves in the absence of T. glabrata.
In the absence of glucose the presence of ethanol in the rumen of young animals can be produced from lactose by a coliform organism.
Floating‐loop Replica‐plating Device
Authors: WIBERG J. S. 
Published: March 2008

The main feature of this device is its ‘floating loops’, which are thin wires formed into loops at one end and mounted in a frame such that the wires are free to move up and down. This feature was incorporated into the ‘applicator’devised by Tarr (1958) for phage‐typing, but has not been as widely used as it merits. The present device was developed independently, without knowledge of Tarr's applicator, and is described here partly to emphasize the advantages of floating loops, and partly to offer an alternative to Tarr's device, both in design and in usage.
Floating loops confer two main advantages over other types of device that pick up droplets of organism suspensions on the ends of rigidly mounted metal rods: (a) a more uniform volume of suspension is delivered, and (b) the loops do not cut into the soft agar in the acceptor Petri dish, since they are very light and ‘float’on the agar.
The device applies 56 standard spots of phage to the surface of seeded agar plates; it has performed satisfactorily in thousands of tests over several years.
Enhancement of the Sensitivity of the Limulus Assay for the Detection of Gram Negative Bacteria
Authors: COATES D. A. 
Published: March 2008

In the Limulus pyrogen assay a linear relationship has been demonstrated between optical density and viable cell number of the strains of Gram negative bacteria studied.
When the bacteria are suspended in a solution of 0.9% saline and 10‐5 M‐ethylenediamine‐tetra‐acetic acid (EDTA) the sensitivity of the assay is markedly improved and the variation between different species or strains is greatly reduced.
The Limulus assay is able to detect fewer than 103 of the least reactive Gram negative bacteria studied within 1 h. It is being developed as a rapid method for detecting Gram negative contamination in raw materials and products.
Suitability of Different Bacterial Groups for Determining Faecal Contamination During Post Scalding Stages in the Processing of Broiler Chickens
Authors: NOTERMANS S. , VAN LEUSDEN F. M. , VAN SCHOTHORST M. 
Published: March 2008

Several bacterial groups were tested for their suitability in determining faecal contamination of carcasses during those stages in poultry processing which follow scalding.Counts of Enterobacteriaceae obtained with the ‘skin‐maceration’method of sampling gave a reliable indication of faecal contamination only when the birds had been scalded at 60° C or above. With lower scald temperatures, none of the bacterial groups tested was found to be suitable as an index of faecal contamination during subsequent processing.
The Relationship Between the Numbers of Rhizobia in Broth and the Quality of Peat‐based Legume Inoculants
Authors: ROUGHLEY R. J. , THOMPSON J. A. 
Published: March 2008

The numbers of rhizobia in unsterilized peat‐based legume inoculants were not significantly related to the numbers in the broths used in their preparation provided the broths contained a minimum of 5 x 108ml‐1.
This relationship was also true for 18 of 19 strains grown in sterilized peat.
It is considered that counting rhizobia in broth culture is unproductive except where the production of inoculants is in its development phase.
A Method for Studying the Activity of Preservatives and its Application to Bronopol
Authors: MOORE K. E. , STRETTON R. J. 
Published: March 2008

A device for dispensing up to 100 1 simultaneously from as many as 24 tubes arranged in a randomized block is described. As the device can also be used for dispensing single drops onto the surface of pre‐dried agar in Petri dishes, it can be used for viable counts.
To validate the technique, dose‐response curves of the preservative bronopol against Pseudomonas aeruginosa were examined.
Microbial Metabolism of Methanol in a Model Activated Sludge System
Authors: SWAIN H. M. , SOMERVILLE H. J. 
Published: March 2008

Methanol is not broken down when added transiently (0.23% v/v) to a model activated sludge system operating with a retention time of 11 h. Measurement of methanol in the effluent agreed closely with calculated values.
Adaptation of the sludge in such a system to 0.1% (v/v) methanol occurs over a period of several days. More than 80% of the methanol is then metabolized.
Methods for the Screening of Amylase‐producing Mutants in Aspergillus niger
Authors: ESWARAN S. , NGA B. H. 
Published: March 2008

Three methods, which made use of amylose azure, a colorimetric reagent for α‐amylase. of screening for amylolytic activity of strains of Aspergillus niger are described.
A high correlation of the corresponding values of amylolytic activity of the strains by these methods was obtained, suggesting that only one needs to be used for an indication of the amylolytic activity of the strains.
The Effect of Medium Volume and Yeast Extract Diffusate on δ–Hemolysin Production by Five Strains of Staphylococcus aureus
Authors: TURNER W. H. 
Published: March 2008

High concentrations of δ–hemolysin were formed by Staphylococcus aureus CN 4108, CN 6730 and CN 6729 growing in 10 ml of medium in baffled shake flasks (100 ml); larger volumes of medium under identical conditions led to the formation of much lower levels of toxin.
Formation of the immunologically‐distinct δ–hemolysin by canine strains CN 7450 and CN 7442 was inhibited when only 10 ml of medium was used in the shake flasks; the toxin was formed when 20 or 30 ml of medium was used.
High levels (40% v/v) of yeast extract diffusate in CCY medium were found to inhibit the formation of δ–hemolysin from strains CN 6729 and CN 7442. Strains CN 6730. CN 4108 and CN 7450 required at least 20, 30 and 40% (all v/v) YED respectively for optimum production of δ‐hemolysin.
Strains CN 4108 and CN 7450 both formed δ‐hemolysin in late log phase.
Degradation of the Mucoid Polysaccharide of Pseudomonas aeruginosa by Beneckea pelagia
Authors: PITT T. L. , RAISBECK L C. 
Published: March 2008

The alginase formed by Beneckea pelagia in sodium alginate medium is weakly active on the mucoid polysaccharide of Pseudomonas aeruginosa.
Supernatants of broth cultures of B. pelagia grown in the presence of Ps. aeruginosa mucoid material had a greater enzymic action on this material than did those grown in alginate broth.
A mucoid strain of Ps. aeruginosa, when grown on nutrient agar to which a dilution of such a supernatant had been added, gave non‐mucoid colonies from which smooth suspensions suitable for agglutination tests could be prepared.
The Occurrence of Salmonellas in Raw Frozen Frog Legs
Authors: SHRIVASTAVA K. P. 
Published: March 2008

In two surveys, salmonellas were recovered from (a) 130 of 325 samples, (b) 36 of 100 pairs of frog legs.
They were present on the surface, in the muscle, saddle and bone‐marrow of frozen frog legs.
The muscles, saddle and bone‐marrow appear to become contaminated during the preprocessing stage, i.e. chopping off, skinning and dressing the hind‐legs.
Effect of Recovery Medium and Incubation Conditions on Bacterial Counts from Plants Treating Aerobic Piggery Waste
Authors: JOHNSTON D. W. , OGILVIE S. M. 
Published: March 2008

Dilute (1/10) strength Oxoid Nutrient Broth (CM1) solidified with agar gave consistently higher colony counts from aerated piggery waste than other media tested.
Maximum colony counts were obtained after 28 d incubation at 20°C.
The Influence of Calcium or Manganese on the Resistance to EDTA, Polymyxin B or Cold Shock, and the Composition of Pseudomonas aeruginosa Grown in Glucose‐ or Magnesium‐depleted Batch Cultures
Authors: KENWARD M. A. , BROWN M. R. W. , FRYER J. J. 
Published: March 2008

Cultures were batch grown in simple salts media in which growth was limited either by depletion of glucose and magnesium (C/Mg‐dep) or by glucose alone (C‐dep). Cultures were also grown in these media supplemented by calcium and/or manganese.All cultures grown in the C‐dep media were sensitive to ethylenediaminetetraacetic acid (EDTA), polymyxin and also to cold shock but were relatively resistant to ethyleneglycol‐bis(2‐aminoethyl ether)‐N, N‐tetraacetic acid (EGTA). Inclusion of calcium or manganese in the growth medium enhanced lysis by EDTA. Cultures grown in the basic C/Mg‐dep media were resistant to EDTA, EGTA, polymyxin and to cold shock. Sensitivity to these agents was retained by cultures grown in C/Mg‐dep media supplemented with Ca2+ and/or Mn2+. Cells grown in C/Mg‐dep media with added Mn2+ were more sensitive to EDTA and polymyxin than those from the unsupplemented C/Mg‐dep media but still resistant compared with C‐dep cultures. All cultures from supplemented C/Mg‐dep media were more sensitive to EGTA than those from any of the C‐dep media.Whole cells and cell walls from these various media had differing amounts of cell wall, phosphorus, amino sugar, carbohydrates, readily extractable lipid (REL), total phospholipid (PL), and especially differences in cell wall divalent metal cation content.The differences in PL, REL and amino sugars and carbohydrate did not correlate with the response of C‐dep and C/Mg‐dep bacteria to EDTA, EGTA or polymyxin. The results are discussed in relation to the hypothesis that the sensitivity of Pseudomonas aeruginosa to polymyxin and EDTA is more dependent on outer membrane cation content rather than on other components, e.g. PL and lipopolysaccharide.
Bacteriological Studies of the Effects of Cow's Milk on Dental Plaque and Dental Caries in Rats
Authors: BEIGHTON D. , MCINTOSH H. A. , MCDOUGALL W. A. 
Published: March 2008

The effects of liquid milk and skim milk powder on the bacterial composition of rat dental plaque and dental caries were examined in two separate experiments. First, groups of rats fed a cariogenic diet plus one or other of three types of liquid milk had. after 28 d. similar plaque flora. Those rats receiving reconstituted spray‐dried skim milk had a significantly higher incidence of dental caries than those receiving either pasteurized and homogenized milk or ultra‐heat treated milk. The differences in caries scores may be related to differences in inorganic phosphate and calcium levels of the milks. Secondly, rats fed a diet containing 65% phosphate‐free sucrose plus 32% spray‐dried skim milk in powder form had a significantly lower dental caries score than did rats receiving a diet containing 65% sucrose plus 32% autoclaved roller‐dried skim milk powder. At the end of this experiment, the plaque flora had changed significantly and the difference in caries incidence was related to the reduction in the percentage of potentially cariogenic bacteria.These results indicate that the mechanism by which milk reduces dental caries incidence may be (a) by remineralizing incipient carious lesions or (b) by mediating changes in the bacterial composition of dental plaque.
Minimal Medium Recovery of Chilled Salmonella Heidelberg
Authors: TANG C. C. , JACKSON H. 
Published: March 2008

1. Salmonella heidelberg, chilled from 37 to 5°C in glucose‐salts broth, grew better on a simple medium (glucose‐salts agar) than on a complex medium (Tryptic Soy Agar + 0·5% yeast extract).2. The organisms recovered the ability to grow on the complex medium after a further 8 h incubation at 5°C.3. RNA synthesis would appear to be a critical factor in the recovery process.
Effect of High Concentrations of Carbon Dioxide on Growth Rate of Pseudomonas fragi, Bacillus cereus and Streptococcus cremoris
Authors: ENFORS S.‐O. , MOLIN G. 
Published: March 2008

The maximum specific growth rates of Pseudomonas fragi, Bacillus cereus and Streptococcus cremoris were studied over a wide range of carbon dioxide concentrations. The growth rate compared with a control was reduced to 50% in Ps. fragi at 0–5 atm CO2, in B. cereus at 1—3 atm and in Strep, cremoris at 8–6 atm. B. cereus and Strep, cremoris were completely inhibited at 3 and 11 atm CO2, respectively. The growth rate of the aerobic Ps. fragi at 0–99 atm CO2 (0–01 atm oxygen) was reduced to about 20% of that in air. The growth rate of Ps. fragi was decreased at oxygen concentrations lower than 0–01 atm.When Ps. fragi was grown at oxygen limitation (0.0025 atm oxygen) and exposed to 0.99 atm CO2, the inhibiting effect of the CO2 was added to that of the oxygen limitation. No indications of a synergistic effect between CO2 inhibition and oxygen limitation were noted.B. cereus and Strep, cremoris were tested under anaerobic conditions.
Quality Control of Solid Culture Media: A Comparison of the Classic and the So‐called Ecometric Technique
Authors: MOSSEL D. A. A. , ROSSEM FRANCINE VAN , KOOPMANS MIRESE , HENDRIKS MIEKE , VEROUDEN MARJON , EELDERINK INEKE 
Published: March 2008

Some selective culture media, prepared from commercially available dried preparations function poorly, and the same applies to an occasional non‐selective culture medium. This calls for systematic monitoring of media before they are used in actual diagnostic work. Classic plating or dilution‐to‐extinction techniques are often found too cumbersome. Hence a simple streaking technique (‘ecometric’ evaluation) was developed earlier for this purpose. It was subsequently simplified further and its accuracy and precision were assessed in this study.After it had been found that the simplified ecometric procedure allowed a reasonably accurate analysis of the selective and productive properties of media, it was used to evaluate 16 selective media, currently used in food microbiology. Results obtained agreed well with observations on the functioning made during routine examination of various foods. Finally an attempt was made to assess whether ecographic inoculation would allow the study of micro‐organisms under repressive conditions, particularly refrigeration temperature. It appeared that this was indeed possible.
Pyrolysis Gas Chromatography of Pseudomonas and Acinetobacter Species
Authors: FRENCH G. L. , GUTTERIDGE C. S. , PHILLIPS I. 
Published: March 2008

Low resolution pyrolysis gas chromatography was performed on five species of Pseudomonas and two species of Acinetobacter. Conventional species groups could be differentiated by canonical variates analysis, and visual examination suggested that subspeciation would have been possible with more data.Carbowax 20M has been used as the stationary phase for the majority of published work on pyrolysis gas chromatography of micro‐organisms. However, with this material baseline resolution was poor, analysis times were long and column deterioration was relatively rapid. Peak area reproducibility on a single column averaged 10%, but it proved impossible to achieve quantitatively similar pyrograms on a new column. These serious drawbacks of Carbowax 20M limit the usefulness of this stationary phase for pyrolysis gas chromatography of micro‐organisms.
Evaluation of Enzyme‐linked Immunosorbent Assay (ELISA) for Serological Identification of Different Rhizobium Strains*
Authors: KISHINEVSKY B. , GURFEL DEBORA 
Published: March 2008

A double‐antidody sandwich method of enzyme‐linked immunosorbent assay (ELISA) previously used for serotyping of peanut Rhizobium isolates was applied for serological identification of fast‐ and slow‐growing Rhizobium strains belonging to different species. This technique is highly sensitive for specific detection of culture and nodule antigens and enabled the rapid screening of large numbers of nodules.ELISA absorbance values of heat‐treated, ultrasonically and mechanically disintegrated cells of the tested strains were consistently higher than those of untreated cells.The antisera to strains R. leguminosarum 250V and R. meliloti 111 obtained from individual rabbits differed in their suitability for ELISA, although they were very efficient in homologous agglutination reactions. The ELISA reactions of culture and nodule antigens were identical for all strains investigated.
A Selective Medium for the Enumeration of Streptococcus bovis by Membrane Filtration
Authors: ORAGUI J. I. , MARA D. D. 
Published: March 2008

A new selective medium (membrane‐bovis agar) for the detection and enumeration of Streptococcus bovis is described. It has been successfully used to quantify this organism in polluted waters, sewage and faeces of humans and farm animals. This medium is based on the ability of Strep. bovis to utilize ammonium sulphate as its sole source of nitrogen. Streptococcus faecalis, Strep. faecium, Strep. equinus, Strep. salivarius. Strep. mitis and other bacteria commonly found in water, sewage and faeces are completely inhibited.Streptococcus bovis appear to be the predominant faecal streptococci in the faeces of farm animals and absent in the faeces of humans. A total of 541 characteristic colonies (on m‐BA), isolated from various sources were identified to species level. Over 97% proved to be Strep. bovis. Therefore, routine confirmatory tests on colonies growing on this medium would appear to be unnecessary.
The Effect of Monensin on Pure and Mixed Cultures of Rumen Bacteria
Authors: HENDERSON C. , STEWART C. S. , NEKREP F. V. 
Published: March 2008

The antibiotic monensin was added to pure cultures of Bacteroides ruminicola, Selenomonas ruminantium, Anaerovibrio lipolytica and Megasphaera elsdenii. These organisms, representing succinate‐ and propionate‐producing rumen bacteria, were not affected by monensin up to 10 μg/ml. Methanobacterium ruminantium was slightly inhibited by monensin, Butyrivibrio fibrisolvens, Ruminococcus albus and Streptococcus bovis were inhibited to differing extents by monensin at concentrations between 0.1 and 10 μg/ml. Bacteroides succinogenes was inhibited at first by monensin at >0.5 μg/ml but after a prolonged lag phase adapted to grow in the presence of monensin at concentrations below 5 μg/ml.Monensin (1 μg/ml) almost completely stopped the digestion of chopped straw and dewaxed cotton fibres by rumen contents incubated in vitro. The digestion of grass and powdered filter paper was not significantly reduced under these conditions, but when the concentration of monensin was increased to between 3 and 5 μg/ml, the digestion of these substrates was reduced.