bluuebunny/crossref_metadata_2025 huggingface dataset:
The Relative Efficacy of Six Selective Media in Isolating Coagulase Positive Staphylococci from Meats
Authors: Jay J. M.
Published: March 2008

Coagulase positive staphylococci were found in 30% of 236 meats when egg yolk agar was used, in 22% of 45 meats when mannitol‐sorbic acid broth was used, in 16% of 70 meats when mannitol‐salt agar was used, in 21% of 146 meats when tellurite‐glycine agar was used, in 8% of 75 meats when polymyxin agar was used and in 7% of 54 meats when Vogel and Johnson agar was used. Of a total of 855 suspect colonies tested from the five solid media, 245 (29%) were coagulase positive. All of the media showed higher percentages of recovery from meats that contained relatively large numbers of staphylococci in proportion to the total number of cocci. The simultaneous use of egg yolk agar and mannitol‐sorbic acid medium gave the best results.
A Rapid, Unequivocal Method for Detecting Glutamic Acid Decarboxylase in Primary Plate Cultures of Enterobacteriaceae
Authors: Stewart D. J.
Published: March 2008

In a rapid technique for detecting L‐glutamic acid decarboxylase activity in lactose fermenting colonies growing on purple MacConkey's agar the colonies, after exposure to toluene vapour for 30 min, are removed from the agar surface with small filter paper discs and allowed to act on a buffered substrate containing 1% of L‐glutamic acid for 1 h. The amino acids are extracted from the disc with a small drop of water and separated by paper chromatography in 1–3 h.

A considerable increase in decarboxylase activity was produced by exposing the cells to toluene vapour. Pyridoxal‐5‐phosphate in the substrate also stimulated activity to a lesser degree.
Sources of the Lactic Acid Bacteria Occurring in Silage
Authors: Stirling Anna C. , Whittenbury R.
Published: March 2008

Lactobacilli, pediococci and leuconostocs were found to be scarce on living undamaged plant tissue. They were not found by direct plating of intact portions of the inflorescence or seed of any plant examined, but they were detected on foliage damaged by insects, on sheaths at the base of grasses and on withered blades of grass. The numbers of lactic acid bacteria on plant material increased during the harvesting and ensiling operations. Many organisms were recovered from the mechanical equipment and the hand implements used during harvesting of the crop.
Studies on Jute Retting Bacteria
Authors: Ahmad M.
Published: March 2008

Summary: A total of 1,438 colonies of aerobic and anaerobic bacteria has been isolated from samples of retted jute stems collected from 12 districts of East Pakistan. Of these, 169 isolates have been purified and characterized. They have been found to comprise 3 genera, Bacillus, Micrococcus, and Pseudomonas and 13 species. Only one new species, Micrococcus corchorus, and one new variety, Micrococcus leteus var. liquefaciens, are reported; these will be described elsewhere.

Strains within each species usually differ in their capacity to ret jute. Active retting strains have been found to lose their retting activity, and it has been concluded that this loss may follow either from loss of adaptive enzymes or from mutations.

Among the aerobes and facultative anaerobes, B. subtilis has been found to be the most common and B. macerans, B. polymyxa, Micrococcus corchorus and Pseudomonas aeruginosa the most active retting agents in East Pakistan. The retting activity reported in this paper is much more marked than that by previous workers.

A detailed description of the process of jute retting is given.
The Effect of Sublethal Heat Treatment on the Growth of Staphylococcus aureus
Authors: Jackson H. , Woodbine M.
Published: March 2008

Summary: When an enterotoxigenic strain of Staphylococcus aureus was subjected to sublethal heat treatment and subsequently inoculated into nutrient broth and incubated at 37° there was a fall in viable numbers. This fall was followed by a lag phase of growth. When the sublethally heated organisms reached the logarithmic phase of growth they showed the same doubling time as unheated organisms. The maximum numbers of organisms reached in nutrient broth was generally the same for heated and unheated organisms. The fall in viable numbers and the delayed lag phase are discussed.
Studies on the Bacteriophagy of Pseudomonas mors‐prunorum, Ps. syringae and Related Organisms
Authors: Crosse J. E. , Garrett Constance M. E.
Published: March 2008

Summary: A group of 23 phages, mainly isolated with Pseudomonas mors‐prunorum and Ps. syringae as the propagating strains, was tested against more than 200 pseudomonads including named plant pathogens and a variety of saprophytes. The majority of the phages had a wide host range, and did not distinguish between plant pathogens and saprophytes, thus confirming the close relationship between these two groups. The most reactive bacteria were 60 English isolates of Ps. mors‐prunorum, 48 from cherry and 12 from plum, and 28 isolates of Ps. syringae from pear. Patterns of reaction within these 3 groups were relatively homogeneous and each group was distinct and differed from all other isolates tested. Ps. syringae isolates from other hosts were less uniform and occasionally shared reaction patterns with other species, e.g. Ps. cannabina and Ps. glycinea. Similar relationships were observed with phages at both high titre and at routine test dilution including the difference in phage sensitivity between the cherry and plum strains of Ps. mors‐prunorum. On the basis of 7 biochemical tests the plum and cherry strains were indistinguishable but they differed from all Ps. syringae isolates tested by giving white growth in 5% sucrose broth and in failing to liquefy gelatin. Furthermore, unlike most Ps. syringae isolates they were also unable to hydrolyze aesculin and were tyrosinase positive. There was no clear evidence in this investigation of correlation between phage sensitivity and biochemical activity. Eleven isolates from various European countries, designated Ps. mors‐prunorum, differed widely both in phage sensitivity and biochemical activity and some of them may be more appropriately called Ps. syringae. Others may be intermediate forms between these species. The relationship between Ps. mors‐prunorum and Ps. syringae and the nomenclature of these organisms are discussed and a concept of ecotypes suggested as a substitute for species.
The Production of Mannosidostreptomycinase
Authors: Shaw R. K.
Published: March 2008

Summary: A medium is described which supports the production of high levels of mannosidostreptomycinase (B'ase) activity by Streptomyces griseus. The enzyme can be utilized to convert streptomycin B to streptomycin A in normal fermentations.
Survival of Freeze Dried Bacterial Cultures
Authors: Steel K. J. , Ross Helen E.
Published: March 2008

The survival of 100 strains of bacteria, representing 15 genera, on freeze drying and during storage in the freeze dried state for 10 years has been assessed. Gram‐positive organisms tended to survive better than Gram‐negative. Viable organisms were recovered from all but one of the cultures.
Factors Affecting the Growth and Fat Formation of Rhodotorula gracilis
Authors: Allen L. A. , Barnard N. H. , Fleming Muriel , Hollis B.
Published: March 2008

Summary: The vitamin requirements of Rhodotorula gracilis are satisfied by inclusion in the growth medium of pantothenic acid and thiamine. For maximum growth in the particular medium and with the size of inoculum used in our experiments a concentration of about 10 μg of pantothenate/1 was sufficient but for rapid early growth a higher concentration was beneficial.

Pantothenic acid can be replaced by β‐alanine but maximum growth response then occurs only in the presence of asparagine. Either ammonium sulphate or urea provides a suitable source of nitrogen for growth of the organism.

Shake flask experiments with a synthetic medium showed that a solution containing only glucose and phosphate was adequate for fattening, that wide limits in pH value (e.g. 4–8) were permissible and that the rate and efficiency of fat production were not affected by large differences in the concentration of sugar.

Provided sugar was still present in the medium a progressive decrease in the percentage of protein was accompanied by a corresponding increase in the percentage of fat in the yeast. When aeration was prolonged beyond the point at which all the sugar was exhausted, this trend was reversed.

The fat produced during fattening had a lower iodine value than that produced during normal growth. Only a small proportion of the fat in Rh. gracilis is in the free condition and extractable by direct treatment with a simple solvent. Preliminary hydrolysis with hot HCl is necessary for quantitative release of the fat.

Refinery cane molasses provides a suitable source of sugar both for growth and for fattening of Rh. gracilis. Growth in a fermentor with incremental feeding, under conditions of high aeration and rapid stirring, gave a yield of dry yeast equivalent to 52–54% of the sugar consumed; the doubling time during the logarithmic growth phase was 3 h.

Aeration of Rh. gracilis in a phosphate‐molasses medium resulted in a rapid consumption of sugar during the whole period of aeration. This was accompanied by an increase in the weight of yeast, accounted for by an increase in all constituents—fat, carbohydrate, mineral matter and a small amount of protein formed from the residual nitrogen carried over from the growth medium. Since much more fat than protein was produced the percentage of fat in the yeast rose and the percentage of protein fell. The proportion of carbohydrate in the cell was subject to some fluctuation. Under certain conditions it appears that the reserves of carbohydrate may be drawn upon to provide energy for fat formation, resulting in an actual destruction of cellular carbohydrate.

The proportion of sugar converted to fat rose to a maximum between c. 14–23 h and then rapidly declined. For a short period a fat coefficient of over 40% was attained in one experiment. Thereafter conversion was relatively inefficient, a small quantity of fat being produced from the consumption of a large quantity of sugar.
An Attempt at Phage Typing in the Genus Serratia
Authors: Pillich J. , Hradečná Z. , Kocur M.
Published: March 2008

Summary: The present report gives the results of the effect of 10 bacteriophages of Serratia marcescens on 107 strains of the genus Serratia. The phage S103 was the most effective (80% strains lyzed), and the phage PK the least (12% strains lyzed). Only 13 strains were resistant to all the phages studied. The majority of the strains of the genus studied could be allocated to one of seven groups on the basis of their sensitivity to the phages.
A Serological Approach to the Genus Pseudomonas
Authors: Hobbs G. , Cann D. C. , Gowland G. , Byers Hilary D.
Published: March 2008

Summary: Serological methods are described by which organisms of the genus Pseudomonas and related genera can be compared. More specific relationships are demonstrated by agglutination techniques or agar diffusion with trichloroacetic acid extracts; less specific relationships are shown by agar diffusion with disintegrated cell preparations. Up to three strain specific antigens may be found and at least six antigens are widely distributed amongst strains of the genera Pseudomonas, Achromobacter, Vibrio and Aeromonas.

The results obtained so far indicate little or no agreement with any accepted taxo‐nomic divisions. Evidence is presented which suggests that most of the antigens detectable by agar diffusion techniques are polysaccharide in nature rather than protein.
A Rapid Method for Isolating Mutants of Bacillus subtilis Producing Increased or Decreased Amounts of the Antibiotic, Mycobacillin
Authors: Banerjee A. B. , Bose S. K.
Published: March 2008

Summary: A simple, rapid and efficient technique is described for the isolation of mutants of Bacillus subtilis in which the synthesis of mycobacillin, an antifungal antibiotic, is blocked. Suspensions of a chosen culture were subjected to ultraviolet radiation and then plated; colonies failing to produce antibiotic were located by flooding the incubated plates with agar seeded with sensitive fungi such as Candida albicans and Aspergillus niger. The method is also applicable for the isolation of high potency strains.
Further Studies on Aeromonas. II. Taxonomy of Aeromonas and C27 Strains
Authors: Eddy B. P. , Carpenter K. Patricia
Published: March 2008

Summary: The results are given of a biochemical study of 21 strains of C27. An Adansonian analysis was carried out by electronic computer on these strains and the Aeromonas strains studied in the previous paper (Eddy, 1962). The analysis confirms the proposal that the C27 strains should be excluded from the genus Aeromonas and a description of the new genus, Plesiomonas (Habs & Schubert, 1962), for these organisms is given. The analysis did not clearly establish Aer. formicans as a species distinct from Aer. punctata.
The Effect of Freezing on the Radiation Sensitivity of Vegetative Bacteria
Authors: Matsuyama A. , Thornley Margaret J. , Ingram M.
Published: March 2008

Summary: Five strains of bacteria were irradiated, suspended in heart infusion broth or in phosphate buffer, in aerated or anoxic conditions, at temperatures of 10–13° or ‐79°. Survivors under the different conditions were enumerated by plate counts on heart infusion agar.

Exponential survivor‐dose curves were obtained with a Pseudomonas strain and with Escherichia coli B/r when irradiated at room temperature with aeration, whereas an Alcaligenes strain and 2 strains of Streptococcus faecium gave sigmoid curves. The decreased radiosensitivity in the frozen state was measured by comparing the D10 values for exponential curves, or for the exponential portion of sigmoid curves, with that observed for irradiation at room temperature with aeration. This ‘D10 ratio’ svaried between 2°5 and 8·5. For the Alcaligenes strain it was about 4, whether the frozen irradiation took place in the presence or absence of oxygen. With the Pseudomonas irradiated in the frozen state in the absence of oxygen the ‘D10 ratio’ was usually about 1·5 times higher than when oxygen was present. The highest ratio (8·5) was obtained for anoxic irradiation of the Pseudomonas strain.

In general, the shapes of survival curves for frozen irradiation differed from those obtained at room temperature. The sigmoid curves for the Alcaligenes strain irradiated under aerobic conditions when frozen showed a marked decrease in extrapolation numbers. E. coli B/r when frozen in heart infusion broth gave a double exponential curve with a shallow slope initially, followed by a steeper slope. The most radiation resistant strain, Strep. faecium R53, gave sigmoid curves with a D10 value of 300 Krads when frozen, and was then of similar resistance to Clostridium botulinum spores.
The Practical Significance in the Microbiological Examination of Cold Stored Foods of the Allegedly Low Heat Resistance among Psychrotrophic Organisms
Authors: Mossel D. A. A. , van de Moosdijk A.
Published: March 2008

Summary: The significance in food microbiology of the observation of Stapert, Sokolski & Northam (1962), that some bacteria occurring in water have such low heat resistances that they would be affected by the warm agar used for pouring plates, was tested. Forty‐two samples of 6 different foods stored for 7 days at 3° to enrich their psychrotrophic microflora, were examined using the same medium, but in thin poured plates and on spread plates, respectively, incubated at 14°. The logarithmic average count of the foods was c. 108/g and included about 60% Gram‐negative rods and 30% cocci. In 90% of the samples no differences were observed between the results from the two methods of counting. The slightly higher spread plate counts in the remaining instances could be accounted for by the increased disruption of bacterial agglomerations always observed in this procedure. Hence there is no reason to query the results of poured plate counts in general. Where it is yet probably safer to use spread plates, rigorous asepsis in pouring and storing should be observed to prevent the development of colonies of contaminants too small to be detected when the plates are inoculated, but leading to erroneous counts after incubation.
Studies on Coli‐aerogenes and Other Gram‐negative Intestinal Bacteria in Various Animals and Birds
Authors: Mushin Rose , Ashburner Frances M.
Published: March 2008

Summary. Some faecal material from native animals and birds (especially) showed either no coli‐aerogenes bacteria or contained types other than Escherichia coli I.

Amongst coli‐aerogenes isolates, E. coli I was frequent but the high percentage of other biotypes indicated that the animal host may serve as a pool of intermediate and irregular strains. Paracolons and Proteus spp. were abundant, and Salmonella spp. were isolated from dogs and native animals possibly in contact with man.

Animals were only occasionally carriers of enteropathogenic E. coli serotypes and seldom of types locally important in the etiology of infantile diarrhoea, such as E. coli O26:B6 and O55:B5. In this series O86 serotypes other than the diarrhoeal strain isolated from babies were found. The results of the study indicated some degree of host specificity. In the group of 20 O serotypes (referred to as specific E. coli), O8 was most commonly listed. Most strains were sensitive to chemotherapeutic agents but resistance of some strains especially to sulphonamide was recorded.

The implication of the presence in the animal gut of coli‐aerogenes bacteria other than E. coli type I is discussed in relation to bacterial standards for drinking water.
The Effect of Electrolytes or Carbohydrates in a Sodium Chloride Deficient Medium on the Formation of Discrete Colonies of Proteus and the Influence of these Substances on Growth in Liquid Culture
Authors: Naylor P. G. D.
Published: March 2008

Summary. Proteus spp. formed discrete colonies on a simple nutrient agar. This lack of swarming was neither a function of electrolyte deficiency nor of low osmotic pressure. If electrolytes and certain carbohydrates were added to such a medium the organism swarmed. Growth studies showed that 0.5% (w/v) NaCl or 2.86% (w/v) dulcitol promoted greater growth than 2.9% (w/v) glucose. Amongst the 9 genera tested only Proteus and Serratia grew better in the presence of NaCl. It is suggested that this growth enhancement is a factor in causing Proteus to swarm.
The Occurrence of Clostridia on Bacon Slaughter Lines
Authors: Baltzer J. , Wilson D. C.
Published: March 2008

Safety in the production of canned meat products depends on the numbers of heat resistant clostridia in the product before processing, as the effect of heat processing is limited. For this reason, the numbers of clostridia in the raw materials are of great importance, and any method which may reduce these numbers is of value.

This investigation has shown that clostridia are present on the rind side of pig carcases at various stages during slaughter operations, the numbers depending on the bacteriological state of the slaughtering equipment. In addition, frozen sections have indicated the presence of clostridia in the deeper layers of the skin. Washing the carcases with hot water besides lowering the aerobic count also reduces the numbers of clostridia.
Sporulation of Clostridium botulinum Type E in Different Culture Media
Authors: Roberts T. A.
Published: March 2008

Twenty‐seven strains of Clostridium botulinum type E were inoculated into six culture media and examined for production of spores. Thirty‐six similar media were then inoculated with each of five strains. Strains varied greatly in their ability to form spores in a given medium. Spore formation varied markedly with casein digests and peptones of different manufacturers. Some differences were broadly indicated between strains from the Pacific and from Scandinavia.
A System for Detecting Salmonellae in Meat and Meat Products
Authors: Georgala D. L. , Boothroyd Margery
Published: March 2008

Leifson's selenite F broth was more selective for salmonellae when incubated at 43° instead of the traditional 37°. Different selective agar media produced different numbers of colonies from similar inocula of salmonella cells, but Difco brilliant green agar consistently gave the highest recoveries when tested in this way. Combined with 43° selenite broth enrichment it provided a useful system for isolating salmonellae from foods. In a short comparative test this system compared favourably with more classical techniques employing enrichment of each sample at 37° in two different enrichment broths, followed by streaking on two selective agars.
A Rapid Screening Test for Aflatoxin‐synthesizing Aspergilli of the flavus‐oryzae Group
Authors: de Vogel P. , van Rhee Renée , Koelensmid W. A. A. Blanche
Published: March 2008

A rapid test for the recognition of aflatoxin‐synthesizing strains of the Aspergillus flavus–oryzae group is described. For this purpose the strains are cultivated on Czapek–Dox agar enriched with an aqueous extract of groundnuts, and in which sodium nitrate is replaced by ammonium chloride. Toxin production is observed by the production of a bright blue fluorescence in the medium when placed under an ultraviolet lamp.
A Note on a Simple and Rapid Method of Bacteriological Sampling by Means of Agar Sausages
Authors: Cate L. Ten
Published: March 2008

A rapid and simple method is described for the bacteriological examination of contaminated surfaces. It uses an imprint process with ‘agar sausages’ sterilized in polyamide casings.
The Aerobic Flora of Stored Meat with Particular Reference to the Use of Selective Media
Authors: Gardner G. A.
Published: March 2008

The changes in the aerobic flora of meats stored at 15, 9 and 4° have been compared by means of selective media and by screening representative isolates. By both methods the predominant spoilage flora at the three temperatures belonged to the genus Pseudomonas. Using the medium of Masurvosky, Goldblith & Voss (1963) preliminary investigations have been made into the numbers of pseudomonads in meats.
The Incidence of Organisms of the Genus Clostridium in Vacuum Packed Fish in the United Kingdom
Authors: Hobbs G. , Cann D. C. , Wilson Barbara B. , Shewan J. M.
Published: March 2008

Of a total of 224 samples of commercial vacuum packed fish products examined for the presence of Clostridium spp., 151 gave positive cultures. The predominant species was Cl. welchii; Cl. botulinum was not isolated. Spore suspensions of 29 strains of Cl. welchii were tested for heat resistance; none survived treatment for 5 min at 100°.
A Modification of the Andersen Sampler for Use in Occupied Environments
Authors: Lidwell O. M. , Noble W. C.
Published: March 2008

In occupied environments the median equivalent diameter of particles carrying airborne bacteria is frequently greater than the 50% cut off diameter, c. 12 μ, of the first stage of the Andersen sampler. By adding a prestage with a 50% cut off at an equivalent particle diameter of c. 19μ the sampler can be adapted for estimating the size distribution of the airborne bacteria‐carrying particles found in these situations.
The Degradation of Gallic Acid and its Alkyl Esters by Pullularia pullulans
Authors: Beveridge E. G. , Hugo W. B.
Published: March 2008

By elective techniques an isolate of Pullularia pullulans was obtained which possessed the ability to utilize gallic acid (3,4,5‐trihydroxybenzoic acid) and its alkyl esters together with other aromatic substrates as the sole carbon source for growth in a mineral salts medium. Quantitative measurements were made of the disappearance of the gallates from culture media and of their metabolism by washed suspensions by the Warburg technique. The pattern of oxygen uptake with various substrates by suspensions adapted to gallic acid was examined in the light of Stanier's simultaneous adaptation postulates in an attempt to identify intermediates of gallic acid metabolism. As a result, β‐ketoadipic acid was suspected of being an intermediate. A keto compound was isolated as its 2,4‐dinitrophenylhydrazone during gallic acid metabolism but it was not β‐ketoadipic acid or levulinic acid.
Effects of Microwave Cookery on the Bacterial Counts of Food
Authors: Lacey Barbara A. , Winner H. I. , Mclellan Margaret E. , Bagshawe K. D.
Published: March 2008

A method is described by which foods drawn from the normal hospital kitchen can be reheated with infrared and microwave irradiation before it is served to patients in an “ultraclean”unit. A considerable reduction in bacterial content has been achieved in all the samples tested and sterility was obtained in some. There was no obvious effect on the palatability of the foodstuffs tested.
A Note on the Microflora of Beef Muscle Stored in Nitrogen at 0°
Authors: Weidemann J. F.
Published: March 2008

Fresh beef stored in nitrogen at 0° was spoiled by Gram positive rods. Almost all the organisms isolated were Microbacterium spp., although in one experiment about 10% of the organisms isolated were Lactobacillus spp. The numbers and types of organisms isolated were similar on each of two media incubated under aerobic and anaerobic conditions.
The Identification of Wild Yeast Colonies on Lysine Agar
Authors: Fowell R. R.
Published: March 2008

The most common wild yeasts infecting pressed baker's yeast in Great Britain are Candida tropicalis, C. krusei, C. mycoderma, Trichosporon cutaneum, Torulopsis candida and Rhodotorula mucilaginosa. Wild yeasts are readily detected and quantitatively estimated by plating infected baker's yeast on lysine agar, which permits of only limited growth of baker's yeast.

Morphology of wild yeast colonies on lysine agar is affected by duration of incubation, location in the agar plate, and sometimes by temperature of incubation, density of infection and numbers of baker's yeast cells present. It is therefore possible to identify each species by at least one characteristic type of colony produced under specified conditions. Ability to grow at 30° and 37° serves to distinguish further between certain species.
The Microbiology of Built Up Poultry Litter
Authors: Schefferle Henrietta E.
Published: March 2008

The numbers of viable bacteria in built up poultry litter were found to be 1010‐1011/g fresh weight and appeared to be little affected by factors such as age, temperature, moisture content and pH. Counts for unused litter and poultry droppings were lower. In built up litter of high alkalinity coryneform bacteria were predominant; micrococci occurred sporadically and small numbers of nocardias, streptomycetes, aerobic spore formers and streptococci were encountered. A variety of Gram negative bacteria also occurred, the numbers of which appeared to be controlled by alkalinity; they were less abundant in litters where the pH and buffering capacity were high. Strongly alkaline conditions also tended to lower the fungal counts but had no effect on the count of enterococci.
The Properties and Classification of the Predominant Bacteria in Rotten Eggs
Authors: Board R. G.
Published: March 2008

A collection of 226 strains of bacteria was assembled from eggs which had rotted on the premises of the producer and from others which had been allowed to rot in the laboratory at 10, 20 or 30°. A majority of the eggs had a mixed infection. All but 8 of the isolates were Gram negative rods. The predominant types were Alcaligenes faecalis, Aeromonas liquefaciens, Proteus vulgaris, Cloaca spp., Citrobacter sp. and Pseudomonas fluorescens. A nonpigmented pseudomonad could not be identified with any of the species included in Pseudomonas.
A Note on the Spoilage of Prepacked Lamb Chops by Microbacterium thermosphactum
Authors: Barlow J. , Kitchell A. G.
Published: March 2008

Summary. The microflora developing at 5° on lamb chops, prepacked commercially, was found to consist largely of facultatively anaerobic, Gram positive, catalase positive, benzidine negative rods resembling Microbacterium thermosphactum. In contrast, beef steaks under the same conditions had a microflora made up predominantly of Gram negative bacteria.
The Dissolved Oxygen and Respiration Rates in Pellicle and Submerged Cultures of Corynebacterium diphtheriae
Authors: Brighton W. D.
Published: March 2008

Summary. The concentration of dissolved oxygen in submerged and static cultures of Corynebacterium diphtheriae was measured with a cathode ray polarograph. In a pellicle culture of the type frequently used for production of diphtheria toxin the concentration of dissolved oxygen in the medium below the pellicle fell sharply after the third or fourth day, and growth then proceeded in a medium which contained only minimal amounts of dissolved oxygen, in spite of the fact that only a cotton wool plug separated the atmosphere above the medium from the outside air.

The measurement of dissolved oxygen in submerged cultures was applied to the determination of respiration rates in growing cultures. The respiration rate for the test organisms varied at different stages in the period of a submerged batch culture. The rate was greatest at the start of the logarithmic phase, and thereafter declined until a steady state was reached.
The Effects of Some Chlorinated Hydrocarbons on Certain Soil Bacteria
Authors: Altman J. , Lawlor Sue
Published: March 2008

Summary. Some common soil bacteria have been shown to tolerate the presence of chlorinated hydrocarbon fumigants. Several of these bacteria indicated an ability to utilize the chemicals as carbon or energy sources. The breakdown of these fumigants may yield compounds either beneficial or detrimental to plants grown in treated soil. Such information is critical to plant disease control since these chemicals are used for the control of plant pathogens, primarily nematodes. It is suggested that the side effects of soil treatment by which plants are stimulated in their growth is a direct consequence of enhanced beneficial microbial activity.
Inhibition of Nitrification in the Activated Sludge Process of Sewage Disposal
Authors: Tomlinson T. G. , Boon A. G. , Trotman C. N. A.
Published: March 2008

Summary. A simple method is described for determining the short term effects of sewages, effluents and individual substances on the nitrifying ability of activated sludge and the results of screening many substances are listed. The effects of mixtures of inhibitors and the possibility of formation of complexes between some of those inhibitors were investigated. The long term effects of inhibitors often differ from their immediate effects, one of the most important factors being the ability of activated sludge to become adapted to the inhibitor.
The Nutritional Requirements and Biochemical Reactions of Corynebacterium bovis
Authors: Harrigan W. F.
Published: March 2008

Summary. The cultural characteristics and biochemical reactions of 142 isolates of Corynebacterium bovis were examined and found to include the production of acid from glucose, fructose and glycerol, and the hydrolysis of urea. The reactions on lipolysis test media were equivocal, in part due to the inability of the organism to grow on some media, and also due to the doubtful validity of using Tween agar to test for lipase production. C. bovis demonstrated a requirement for serum, Tween 20 or 80, or egg yolk. In experiments carried out with fully defined liquid media this nutritional requirement was fulfilled by synthetic lecithin or Tween 80, or a mixture of both compounds.
An Improved Simple Macrorespirometer
Authors: Harris P. J.
Published: March 2008

Summary. A simple soil respiration apparatus is described which minimizes the effects of fluctuations of atmospheric temperature and pressure.
The Microflora of Poorly Cleansed Farm Dairy Equipment
Authors: Thomas S. B. , Druce R. G. , King Kay P.
Published: March 2008

Summary. A series of 170 rinses and 14 milk residue deposits from poorly cleansed dairy equipment on 136 farms, giving colony counts at 30° of > 106/ft2 for rinses or /g wet wt for residues, were classified into 8 groups according to the composition and milk spoilage activity of their microflora. Five of the groups were dominated by active milk spoilage types of bacteria and three by inactive organisms. Micrococci, coryneform bacteria and aerobic sporeforming rods dominated the microflora of 1/3 of the 184 samples. Gram negative rods, including coli‐aerogenes organisms, were dominant in another 1/3, a combination of micrococci, coryneform bacteria and Gram negative rods constituted the microflora of 19% and streptococci were dominant in 10%. Active milk spoilage types of bacteria were predominant in 106 (58%) of the rinses and deposits, but inactive types forming no reaction in litmus milk in 72 h at 22° were dominant in 78 (42%).
The Use of Inoculation and Pelleting in the Establishment of White Clover under Mountain Conditions
Authors: Jones D. Gareth , Thomas S. B.
Published: March 2008

Summary. Aberystwyth S.184 and New Zealand Certified Mother white clover (Trifolium repens) seed was inoculated with an effective strain of Rhizobium trifolii and pelleted with lime and lime and Gafsa phosphate. When sown in conjunction with S.59 red fescue (Festuca rubra) on rotary cultivated Nardus‐Festuca mountain pasture treated seed gave a significantly better establishment of clover than the uninoculated, non‐pelleted seed of the same varieties.
The Effects of Sulphite Preservative in British Fresh Sausages
Authors: Dyett E. J. , Shelley Deirder
Published: March 2008

Summary. The bacteriology of pork and beef sausages, with and without metabisulphite preservative, when stored at room temperature and 3—5° is described. The preservative has a marked effect on microbial growth in sausages stored at room temperature, particularly with regard to the organisms found on plates incubated at 37°. Of the latter, coli‐aerogenes and other Gram negative organisms were the most inhibited by the preservative.
A Selective Medium for the Enumeration of Microbacterium thermosphactum in Meat and Meat Products
Authors: Gardner G. A.
Published: March 2008

Summary. A selective medium for the isolation and enumeration of Microbacterium thermosphactum is described and data is presented on its use in assessing the composition of the flora of meat and meat products.
Characteristics of Staphylococci and Micrococci isolated in a Bacon Curing Factory
Authors: Patterson J. T.
Published: March 2008

Summary. The majority of 164 strains of staphylococci and micrococci isolated from fresh pork, curing brines and bacon fell into Shaw subgroups 2 and 3. The strains were tolerant to nitrite, but this was toxic in high concentration, particularly at low pH. Although arginine was attacked by many strains, there was little decarboxylase or deaminase activity with the other amino acids tested. The heat resistance of the strains was generally < 30 min at 60°. The lipolytic activity of the bacon isolates was studied using tributyrin, lard, butter, triolein and palm kernel oil as substrates. The hydrolysis of tributyrin occurred with a number of strains in the presence of 5% of salt, 2% of potassium nitrate and 100 p of sodium nitrite/m and at 4°.
The Use of Ferritin Labelled Antibodies in the Location of Spore and Vegetative Antigens of Bacillus cereus
Authors: Walker P. D. , Baillie Ann , Thomson R. O. , Batty Irene
Published: March 2008

Summary. Ferritin labelled antibodies have been used to detect the presence of vegetative antigens in spores. The specificity of the labelled antibodies was demonstrated. Vegetative antigens were found along the core or cortical membrane in spore disintegrates, and after germination along the developing vegetative cell wall. The implications of these results are discussed in relation to morphological studies of ultra‐thin sections.
A Comparison of Toxin Production by Clostridium botulinum Type E in Irradiated and Unirradiated Vacuum Packed Fish
Authors: Cann D. C. , Wilson Barbara B. , Shewan J. M. , Roberts T. A. , Rhodes D. N.
Published: March 2008

Summary. The rates of toxin production at 10° by inocula of 105, 104, 103 and 102 spores of Clostridium botulinum type E in vacuum packed herring, cod and haddock were compared with that of equivalent numbers of spores surviving γ‐irradiation at 0.3 Mrad. There was little difference between the rates of toxin production in unirradiated and irradiated fish. More toxin was produced in irradiated herring than in unirradiated, but in haddock the reverse was obtained. In cod about equal amounts of toxin were found without trypsinization; after trypsinization toxin levels were generally higher in irradiated samples.
Observations on Halogens as Bathing Water Disinfectants
Authors: Brown J. R. , McLean D. M.
Published: March 2008

Summary. The biocidal activities of the halogens are reviewed. Bromine concentrations exceeding 2 p/m will produce water of acceptable bacteriological quality. In paddling pool water, bromine was less bactericidal than iodine against the staphylococci, enterococci and diphtheroids.
Methods of Examining Damp Grain at Harvest and After Sealed and Open Storage: Changes in the Microflora of Damp Grain during Sealed Storage
Authors: Nichols Agnes A. , Leaver Christine W.
Published: March 2008

Summary. Methods are described for enumerating the micro‐organisms occurring on damp grain (18–35% moisture content) after harvesting and after sealed and open storage.

The microflora of 41 samples of damp grain at harvesting and 137 samples after sealed storage on farms have been examined. The latter included 25 samples from experimental storage, including polythene bags, and 51 samples from stores where spoilage had occurred or advice was sought.

A remarkably consistent population level of bacteria, moulds and yeasts was found on damp grain at harvesting. This information was used as a convenient basis for comparisons with results from grain after storage. Bacteria were initially present at 1–10 × 106/g, but the level generally diminished during anaerobic storage. Also coli‐aerogenes bacteria died out but lactobacilli increased. Strict anaerobes (Clostridium spp.) did not develop. Moulds originally present in small numbers normally decreased but while total yeasts often remained at the ingoing number, there was a change from non‐myceliated to myceliated species, numbers of which sometimes increased further.

If thermophilic yeasts and moulds or Streptomycetaceae were present in large numbers, the grain had been subjected to aeration and had heated. Sometimes mould growth appeared to cause binding of the grain, but in other instances myceliated yeasts were implicated.
Coli‐aerogenes Bacteria on Plants
Authors: Papavassiliou J. , Tzannetis S. , Leka Helen , Michopoulos G.
Published: March 2008

Summary. Specimens of plant foliage and flowers collected in the region of Attica from various situations and geographical regions were examined over a period of 13 months for the presence of coli‐aerogenes bacteria able to grow at 37°. Twenty‐five (12.2%) of 204 specimens carried coli‐aerogenes bacteria of which Escherichia coli type I was isolated from 12 (5.8%). Coli‐aerogenes bacteria were seldom isolated from plants grown in uninhabited areas, and they occured more frequently during summer and autumn.

Vegetables and fruits sold in the central market of Athens are frequently contaminated with coli‐aerogenes bacteria. Of 76 specimens of vegetables examined 66 (86.8%) were positive for coli‐aerogenes bacteria, and 17 (22.3%) for E. coli type I. The figures from 41 specimens of fruits were 26 (65.8%) and 4 (9.7%), respectively.
Effect of Oxygen Tension on the Spoilage Microflora of Irradiated and Non‐irradiated Haddock (Melanogrammus aeglefinus) Fillets
Authors: Licciardello J. J. , Ronsivalli L. J. , Slavin J. W.
Published: March 2008

Summary. The spoilage microflora of irradiated and non‐irradiated air packed or vacuum packed haddock fillets was identified after storage of the fillets at 35°F. With the non‐irradiated fillets, both air packed and vacuum packed, the spoilage flora was predominantly pseudomonads. With the irradiated fillets, the spoilage flora of the air packed samples was chiefly achromobacter; that of the vacuum packed samples was chiefly lactobacilli (or possibly Microbacterium thermosphactum).
Improved Control of Organism Concentration in Continuous Cultures of Filamentous Micro‐organisms
Authors: Righelato R. C. , Pirt S. J.
Published: March 2008

Summary. Mycelium concentration and culture volume measurements in continuous cultures are affected by accretions of filamentous organisms at the overflow weir. A pinch valve is described which periodically closed the air and culture effluent tube. When released the outrush of air cleared the overflow system. With the device the standard deviations of the steady state mycelium dry weights were reduced to one third of their former value and progressive concentration of the organism was eliminated. Measurement of culture volume was corrected for gas retained in the mycelial mass.
Use of the Coulter Counter to Measure the Swelling of Bacterial Spores during Germination and Outgrowth
Authors: Parker M. S. , Barnes Mary
Published: March 2008

An electronic counting and sizing instrument has been used to measure the swelling of spores of Bacillus subtilis during the germination process and to detect and measure outgrown cells.
Bacteriology of Prepacked Pork with Reference to the Gas Composition within the Pack
Authors: Gardner G. A. , Carson A. W. , Patton J.
Published: March 2008

Bacteriological changes in pork stored at 16 and 2° under gas permeable and gas impermeable films and ‘aerobic’conditions have been studied. The concentrations of CO2, O2 and N2 in the atmosphere within the packs were also determined. The groups of bacteria isolated from prepacked pork were Pseudomonas‐Achromobacter spp., Kurthia spp., Microbacterium thermosphactum, Enterobacter‐Hafnia spp. and lactobacilli. Their importance is discussed in relation to storage temperature and gas composition within the packs.
Antigenic Analysis of the Digests of the Crystal Toxins of Bacillus thuringiensis
Authors: Pendleton I. R. , Morrison R. B.
Published: March 2008

Protein crystal toxins from 93 isolates of the Bacillus thuringiensis group of organisms were digested with proteases from the gut of larvae of Pieris brassicae. An antigenic analysis was made of these digests and the results compared with the previously determined antigenic patterns of solutions of the crystals. Digestion led to the loss of some antigens and occasionally to the gain of others. Fewer distinctive antigenic patterns were found in the digests than in the crystal solutions.
Yeast Flora of Cider Factories
Authors: Bowen J. F. , Beech F. W.
Published: March 2008

Harvested and stored fruit, and juice collected from the cider press, showed larger numbers and a wider range of yeast species than did fruit picked aseptically from the tree. The ratios of species changed during storage. Under clean factory conditions or in the pilot plant the range of species was limited. Saccharomyces spp. and other spore‐formers were absent, possibly having been eliminated by thorough cleaning of equipment. Kloeckera spp. which increased markedly on the fruit during harvesting and storage, remained as an appreciable component of the juice microflora. Factories with less rigid standards of sanitation harboured a much wider range of yeasts. Saccharomyces spp. and extraneous sporeformers, which were rarely detected on the whole fruit, appeared in the freshly pressed juice, and together with Kloeckera spp., made up a large proportion of the microflora. The undesirable sporeforming spp., Saccharomycodes and Hansenula, were detected in some instances.
A Divided Petri Dish for Use with Multipoint Inoculators
Authors: Sneath P. H. A. , Stevens M.
Published: March 2008

A sterile disposable plastic Petri dish is described that is divided internally into 25 separate wells. It is designed for use with multipoint inoculators, and allows many commonly used tests to be performed quickly and cheaply. It can also be used for making aseptic serial dilutions.
Structure of Bacillus stearothermophilus: An Electron Microscope Study
Authors: Walker P. D. , Baillie Ann
Published: March 2008

The fine structure of Bacillus stearothermophilus and related organisms is described using the technique of ultrathin sectioning.
Growth and Toxin Production of Clostridium botulinum type E
Authors: Ajmal M.
Published: March 2008

Growth and toxin production of Clostridium botulinum type E was studied at 37, 30, 22 and 4°. Incubation at 30° yielded maximum numbers of viable cells but the toxicity was not different from cultures grown at 22°, thus indicating that the toxin synthesis/cell was greater at the latter temperature. Growth as well as toxin production was less pronounced at 37°. The ability to grow at 4° was influenced by the medium and the type of inoculum used. The role of the enzymic activity of the culture during and after the exponential phase of growth is emphasized in relation to the final toxicity of type E cultures in terms of MLD/ml.
Effect of some Preslaughter Treatments on the Salmonella Population in the Bovine Rumen and Faeces
Authors: Grau F. H. , Brownlie L. E. , Roberts E. A.
Published: March 2008

Salmonella spp. were detected commonly in railway wagons, saleyards and abattoir holding pens through which cattle pass from farm to slaughter. The salmonellae population in the rumen and faeces of cattle at slaughter depended on the previous treatment of the animal. The percentage of animals with salmonellae in the rumen was greater the longer the period between leaving the farm and slaughter; feeding once during this period increased the incidence and numbers of salmonellae in the rumen and at least the incidence in the faeces.
Sterilization of Syringes by Ethylene Oxide
Authors: Rubbo S. D. , Gardner Joan F.
Published: March 2008

Three types of disposable syringe, all known to be sterilized commercially by ethylene oxide, were contaminated with Bacillus subtilis spores at the most inaccessible site, between plunger and barrel, and processed under controlled conditions. The rate of failure in sterilization was related to the syringe design as well as to the number of spores initially present. Rubber tippe plungers forming a double edge contact with the barrel failed to a degree that varied with the thickness of the contacting edges and the tightness of fit in the barrel. Although ethylene oxide may be used if initial contamination is low, gamma radiation would be more reliable for this type of syringe.
Resistance to Paromomycin, Bacitracin and Novobiocin in the Micrococcaceae
Authors: Lacey R. W. , Boswell P. A.
Published: March 2008

The characteristic antibiotic sensitivity pattern of Micrococcus luteus strengthens its case for a distinct taxonomic category. Paromomycin resistance may be useful in identifying this organism.
Design of High Power Magnetic Drives
Authors: Cameron J. , Godfrey E. I.
Published: March 2008

The construction of high power magnetic drives operating at speeds of 300‐ > 2000 rev/min for use in mixing and deep culture vessels of 5–300 1 capacity is described.
Sensitivity to Novobiocin and Lysozyme in the Classification of Micrococcaceae
Authors: Jeffries L.
Published: March 2008

Sensitivity to novobiocin and lysozyme has been determined on strains of Micrococcaceae classified by biochemical and physiological tests, and also on pigmented micrococci and planococci of known guanine + cytosine (GC) content in DNA. These tests confirm the homogeneity of strains within certain proposed subgroups and also the heterogeneity of others, notably strains in Baird‐Parker's Micrococcus subgroup 7. The results of lysozyme and novobiocin sensitivity determinations, on strains intermediate in GC content between the suggested ranges for the genera Staphylococcus and Micrococcus, and also on atypical strains of staphylococci, are presented and discussed.
Activity of Metronidazole against Experimental Tetanus and Gas Gangrene
Authors: Freeman W. A. , McFadzean J. A. , Whelan J. P. F.
Published: March 2008

Metronidazole, a compound widely used in man with minimal side effects, has been shown to be highly active against experimental infections of Clostridium tetani and Cl. welchii in mice. It is too early to forecast what role the compound might have in the chemoprophylaxis of these infections in man.