bluuebunny/crossref_metadata_2025 huggingface dataset:
A Medium for Overcoming the in vitro Inhibition of Clostridium perfringens by Streptococcus faecalis var. zymogenes, and a Note on the in vivo Interaction of the Two Organisms
Authors: Jayne‐Williams D. J.
Published: March 2008

Summary. The presence of Streptococcus zymogenes in samples plated for the enumeration of Clostridium perfringens markedly reduces the numbers of clostridial colonies. This effect is not overcome by the use of media usually recommended for the selective isolation of Cl. perfringens, but an agar medium containing 100 μg of both D‐cycloserine and neomycin/ml proved satisfactory. Use of this medium for estimating numbers of Cl. perfringens in the gut of gnotobiotic quail has shown that inhibition by Strep. zymogene does not appear to occur in vivo.
Rapid Methods for the Determination of Faecal Contamination in Oysters
Authors: Qadri R. B. , Buckle K. A. , Edwards R. A.
Published: March 2008

Summary. Two methods for the rapid detection and estimation of numbers of faecal coliforms and Escherichia coli type I in oysters have been developed. That for faecal coliforms involves incubation of tubes of MacConkey broth for 2 h at 37° and then for 22–24 h at 44°. The second method, a modification of MacKenzie, Taylor & Gilbert's (1948) specific method for E. coli type I, makes use of the same system of incubation, but requires the inoculation of tubes of peptone water as well as MacConkey broth, the former tubes being used for subsequent testing for indole formation. Both methods take only 24–26 h and are as sensitive and accurate as the Most Probable Number methods which are in common use and which take upwards of 72–96 h to complete.
Some Observations on the Colony Morphology of ‘Corroding Bacilli’
Authors: Robinson J. V. A. , James A. L.
Published: March 2008

Summary. Pitting, spreading and domed colonies of strictly anaerobic and facultatively anaerobic strains of ‘corroding bacilli’were induced by varying the culture conditions. Colony form seemed to depend on 2 factors, the availability of certain nutrients and the condition of the bacteria at the time of inoculation.
Further Observations on the Toxicity of Navy Beans (Phaseolus vulgaris) for Japanese Quail (Coturnix coturnix japonica)
Authors: Jayne‐Williams D. J. , Burgess C. D.
Published: March 2008

Summary. The lethal and growth depressing effects of feeding raw navy beans (RNB) to Japanese quail have been shown to be due neither to poor palatability nor to dialysable, lipid or carbohydrate constituents, but to a protein material soluble at pH 3 and precipitable by saturation with (NH4)2SO4. This material proved resistant to digestion by pepsin and proteolytic bacteria but was destroyed by autoclaving at 121° for 15 min. Germfree birds given a diet containing RNB which had been fermented by coliforms grew well, indicating that toxicity of RNB is not dependent on the release by intestinal bacteria of poisons from innocuous precursors in the beans. Examination of the effects of feeding diets containing other raw legume seeds to quail have shown that toxicity is associated with the presence of high concentrations of phytohaemagglutinins (PHAs). Quail given RNB diet showed a greater incidence of liver infection than birds fed an autoclaved bean diet but bacteriological examination of gut contents of such birds revealed no marked qualitative or quantitative differences. Chemical examination of gut contents likewise revealed no marked differences. Experiments with gnotobiotic quail showed that coliforms derived from a variety of sources were capable of causing the death of birds on RNB diet and that the numbers attained in different parts of the intestine by a single coliform strain were not affected by the diet fed. The results suggest that toxicity of RNB may be due to impairment of body defence mechanisms by PHA leading to tissue invasion by normally innocuous components of the intestinal microflora.
Factors Affecting the Viability of Mycoplasma mycoides in Bottled Contagious Bovine Pleuropneumonia Vaccine
Authors: Lloyd L. C. , Pearson Catherine W. , Etheridge J. R.
Published: March 2008

Summary. Some of the factors contributing to the loss of viability of V5 contagious bovine pleuropneumonia vaccine in BVFOS medium during storage were investigated. Results showed that: 1, some types of rubber stoppers were highly toxic to Mycoplasma mycoides; 2, loss of viability was greater when the vaccine was stored in smaller bottles and was related to the proportionately greater air space; 3, the addition of glycerol to BVFOS medium resulted in slightly better survival during storage at 37° but decreased survival at 4°; 4, small bottles can be filled to higher levels, and the air space reduced, if the mouth of the bottle is protected during incubation by a metal cover instead of a cotton wool plug. It is recommended that the amount of air space should not exceed 40% of the volume of the bottle, the vaccine should be stoppered with non‐toxic stoppers after incubation and the BVFOS medium should not be supplemented with glycerol. Vaccine prepared in this way should maintain a viable count of 107 or more organisms/ml during storage at 4° for at least 12 weeks.
The Incidence of Enterotoxin Production in Strains of Staphylococcus aureus Isolated from Foods
Authors: Payne D. N. , Wood J. M.
Published: March 2008

Summary. The production of staphylococcal enterotoxins A, B, C, D and E among 200 strains of Staphylococcus aureus was surveyed using a double diffusion immunoprecipitation technique. Enterotoxin A was found to occur most frequently and enterotoxin B least frequently. The distribution of enterotoxigenicity in strains isolated from meat products differed from that of strains isolated from dairy products. The correlations of porcine plasma coagulation and of bacteriophage pattern with enterotoxigenicity were determined.
A Thin‐Layer Chromatographic Technique for Rapid Estimation of Bacterial Lipases
Authors: Legakis N. , Papavassiliou J.
Published: March 2008

Summary. A thin‐layer chromatographic technique for the estimation of lipase in Pseudomonas aeruginosa and staphylococci is described. The technique needs a short incubation period (4 h), while the subsequent procedure is quite simple and rapid. The validity of the technique was established by testing 56 strains of Ps. aeruginosa and 35 strains of staphylococci. The results strongly support the usefulness of the technique which can be quite easily applied to routine use.
Erwinia rhapontici (Millard) Burkholder Associated with Pink Grain of Wheat
Authors: Roberts Pauline
Published: March 2008

Summary. Bacteria isolated from pink‐coloured grains of English wheat were identified as Erwinia rhapontici, and were identical with isolates made by Luisetti & Rapilly (1967) from wheat with a similar disorder in France. Pink grain was reproduced with English and French isolates and with authentic cultures of E. rhapontici when developing grain of wheat plants was inoculated, but only after wounding.
Daily Variations in the Production of Aflatoxins by Aspergillus flavus NRRL‐3145 Following Exposure to 60Co Irradiation
Authors: Applegate K. L. , Chipley J. R.
Published: March 2008

Summary. Spores of the toxigenic fungus Aspergillus flavus NRRL‐3145 were exposed to γ‐irradiation and allowed to germinate. The increase in the production of aflatoxins B1 and B2 following inoculation on cracked red wheat or in a liquid synthetic medium was greater than that which occurred in similarly treated cultures derived from non‐irradiated spores. Variations in aflatoxin production were also observed daily for both the control and irradiated cultures developing on both media, with maximum toxin production varying from 2–10 days of incubation. The most notable increases in aflatoxin production occurred from cultures that developed from spores irradiated with 150, 200 or 300 krad. Exposure to 400 or 600 krad resulted in the complete inhibition of spore germination and, consequently, no aflatoxin was produced. The quantities of B2 toxin produced were significantly lower than that of B1 toxin, except in the synthetic medium where B2 production was comparable with that of B1. Cultures developing from non‐irradiated spores exhibited a diphasic curve in production of aflatoxin G1 when grown on wheat, with maximum toxin production occurring on the 4th and 10th day of incubation, while in the synthetic medium, G1 production occurred as a monophasic curve. In the wheat, irradiation of A. flavus spores with 25, 100, 150, 200 or 300 krad caused significant increases of G1 toxin over the amounts of the same toxin produced by non‐irradiated controls. Similarly, exposure of spores to 200 krad and subsequent growth in a liquid synthetic medium resulted in significant increases in the amounts of G1 toxin produced compared with non‐irradiated controls. Except for the 200 krad irradiation, the amounts of G2 toxin produced daily by spores were generally lower than those of G1 toxin in either the wheat or the synthetic medium. Media, time of incubation and selected irradiation levels affected the daily and total amounts of aflatoxins produced.
Rapid Screening for the Isolation of Mutants of Aspergillus nidulans with Increased Penicillin Yields
Authors: Ditchburn P. , Giddings B. , Macdonald K. D.
Published: March 2008

Summary. After UV treatment conidia of a strain of Aspergillus nidulans were plated on an agar medium. The survivors gave rise to individual colonies which were inoculated separately on agar discs and incubated. The discs were then transferred to biological assay plates seeded with spores of a strain of Bacillus subtilis sensitive to penicillin. Using this primary screening method, mutants have been isolated which, when tested later in shake flask cultures, gave larger penicillin yields than the parent strains.
Biological Control of Crown Gall: Seed and Root Inoculation
Authors: Htay Khin , Kerr A.
Published: March 2008

Summary. Experiments on the control of crown gall by inoculating susceptible plants with a non‐pathogenic strain of Agrobacterium radiobacter have continued. In all experiments, highly significant disease control was achieved. In one experiment, 42% of untreated plants growing in soil heavily infested with A. radiobacter var. tumefaciens died; inoculation of seed with the non‐pathogenic strain reduced this to nil. Combined seed and root inoculation was more efficient than seed inoculation alone. In naturally infested soil, combined seed and root inoculation at transplanting gave 99% control of gall formation (as dry weight). A significant increase in plant growth resulted from combined seed and root inoculation. At transplanting, roots should probably be inoculated within 2 h of lifting. This method of biological control is now widely practised by commercial growers in South Australia.
Physical Responses of Yeast Cells to Osmotic Shock
Authors: ROSE D.
Published: March 2008

Shock exposure of the osmophilic yeasts Saccharomyces rouxii, Torulopsis globosa and T. apicola to solutions of sucrose and polyethylene glycol of MW 200 (PEG 200) at water activity (aw) values between 0.88 and 0.98 caused gradual changes in cell volumes in the test solutions, though cell volumes were consistently lower in PEG 200. Non‐osmophilic yeasts, Sacch. cerevisiae, bakers’yeast and Schizosaccaromyces pombé showed responses similar to the osmophiles in sucrose solutions only, as cells in PEG 200 apparently equilibrated with external osmotic pressures by uptake of solute. Optical densities of cell suspensions supported the findings on cell volumes. Viability tests at the highest and lowest solute concentrations indicated that all test organisms withstood the osmotic shock over the test period. As the theoretical relationship between aw and osmotic pressure breaks down in concentrated solutions, it is considered that the water relations of yeasts should not be considered exclusively in terms of aw, but also in conjunction with osmotic pressure and solute uptake.
Incidence of Salmonellae in Animal Feed and the Effect of Pelleting on Content of Enterobacteriaceae
Authors: STOTT J. A. , HODGSON J. E. , CHANEY JANE C.
Published: March 2008

During a survey of meat and bone meals, fish meals and poultry feeds salmonellae were found only in samples of meat and bone meal, for which 19% were Salmonella‐positive. MPN estimations on 2 meat and bone meal samples gave figures of 6 and 39 salmonellae/ 100 g, respectively. Sampling of poultry feed before and after pelleting showed that this process gave up to 1000‐fold reduction in numbers of Enterobacteriaceae depending on the type of processing involved.
Protein Changes Caused by Bacterial Growth on Beef
Authors: DAINTY R. H. , SHAW B. G. , DE BOER KLASKA A. , SCHEPS ELLY S. J.
Published: March 2008

Proteolysis could not be detected, prior to the appearance of spoilage odours and surface slime, in beef allowed to spoil aerobically at 5° with its own natural flora or after inoculation with a reconstituted freeze‐dried beef slime. Although the slime inoculum gave a final microbial flora similar to the naturally‐attained one, it resulted in more rapid and extensive post‐spoilage proteolysis. Pure culture experiments showed that proteolysis was probably due to the activities of Gram negative organisms.
An Evaluation of the Carbon Dioxide Component in the GasPak Anaerobic System
Authors: FERGUSON I. R. , PHILLIPS K. D. , TEARLE P. V.
Published: March 2008

The GasPak disposable hydrogen and carbon dioxide generator is a convenient and reliable method for producing anaerobiosis in the GasPak system. As a source of carbon dioxide, however, the generator is inadequate, uncontrolled and unreliable.
pH and Eh in Single and Mixed Culture Bacterial Plaque in an Artificial Mouth
Authors: COULTER W. A. , RUSSELL C.
Published: March 2008

The pH and Eh of bacterial plaques produced on a tooth surface in an artificial mouth following inoculation with saliva, single cultures and mixed cultures were measured. The importance of these properties and the role of sucrose in controlling colonization by specific organisms, particularly anaerobes, was investigated. The degree of colonization was estimated from the viable counts in the effluent from the tooth. Interactions between the bacterial species in the multi‐culture plaques are discussed. The results are presented in support of the hypothesis that colonization of the teeth by anaerobes depends upon prior growth of aerobes during early plaque formation.
A New Method for Strain Identification of Rhizobium trifolii in Nodules
Authors: CLOONAN M. J. , HUMPHREY BEVERLEY
Published: March 2008

An indirect haemagglutination test has been developed for the detection of strains of Rhizobium trifolii in nodules of subterranean clover plants. Preserved sheep red blood cells, coated with isolated specific rhizobial lipopolysaccharide, were used as the indicator of agglutination; these cells were agglutinated by specific antilipopolysaccharide antibody. Detection of lipopolysaccharide antigen in a suspension of nodular tissue was carried out by reacting the suspension with antilipopolysaccharide antibody prior to the addition of coated red blood cells. The presence of antigen in the suspension was indicated by an inhibition of agglutination. The test was more sensitive than agglutination and immunodiffusion in the detection of rhizobial lipopolysaccharide antigens, and could be used for the rapid screening of large numbers of nodules.
Studies of the Utilization of Coconut Water Waste for the Production of the Food Yeast Saccharomyces fragilis
Authors: SMITH M. E. , BULL A. T.
Published: March 2008

The accepted food yeast Saccharomyces fragilis was grown in batch and chemostat culture on coconut water and on a simulated coconut‐water medium containing glucose, fructose, sucrose and sorbitol, to provide kinetic data for a feasibility study of microbial protein production. Analyses of growth on individual and mixed carbon substrates were made to determine sugar assimilation patterns in batch and chemostat cultures on coconut water. Growth on the polyol produced a much reduced specific growth rate, assimilation rate, growth yield and productivity compared to growth on the sugars. In mixed substrate fermentations a sequential utilization of the carbohydrates occurred. Both the monosaccharides repressed invertase synthesis and all three sugars repressed sorbitol assimilation. Complete carbon assimilation was only obtained by prolonged batch fermentation or in chemostat cultures at low dilution rates (<0.10 h‐1). Supplementation of coconut water with biotin and nicotinic acid increased biomass yields in chemostat cultures.
Antibacterial Activity of Ambodryl and Benadryl
Authors: DASTIDAR SUJATA G. , SAHA P. K. , SANYAMAT B. , CHAKRABARTY A. N.
Published: March 2008

Of nine antihistamines screened for in vitro antibacterial activity, ambodryl (bromodiphenhydramine hydrochloride) and benadryl (diphenhydramine hydrochloride) were the most active. At 50 to 100 μ/ml concentrations these inhibited a large number of Gram negative and Gram positive bacteria in vitro, with ambodryl having a broader spectrum. In vivo tests showed that the compounds at single doses of 3 and 1.5 μg/g body weight protected mice against a challenge with a virulent strain (LD50) of Salmonella typhimurium, and also significantly reduced the multiplication of this organism in the liver, spleen and blood of the protected animals in comparison with the unprotected controls.
Susceptibility to Phosphomycin as a Differential Character for Gram Negative Anaerobic Bacilli
Authors: RODRIGUEZ J. A. GARCIA , PRIETO J. PRIETO , SANCHEZ J. E. GARCIA , GONZALEZ M. C. SAENZ , LUENGO F. MARTIN
Published: March 2008

On the basis of their sensitivity to phosphomycin, various species of anaerobic Gram negative bacilli examined fell into one of two groups. All strains of Bacteroides were resistant to 500 umg/ml whereas strains of Fusobacterium were uniformly sensitive to 62.5 μg/ml. Disc sensitivity testing to phosphomycin at concentrations of 200–500 μg/ml provides a reliable and rapid means of distinguishing fusobacteria from bacteroides.
Filter Mud as a Carrier for Rhizobium Inoculants
Authors: PHILPOTTS HELEN
Published: March 2008

Laboratory tests indicated that filter mud, a waste product from sugar cane mills, proved to be a suitable carrier for Rhizobium inoculants, provided it was not dried by heating. Autoclaving air dried material was not detrimental and ensured high survival when held at room temperature. The adverse effect of oven drying, which was increased by subsequent autoclaving or gamma irradiation, lessened with time.
A Simple Procedure for Screening of Salmonellae using a Semi‐Solid Enrichment and a Semi‐Solid Indicator Medium
Authors: CHAU P. Y. , HUANG C. T.
Published: March 2008

The incorporation of triphenylmethane dyes and divalent cations in a semi‐solid medium in conjunction with a low pH retarded the motility of most enteric bacteria except for Salmonella, Enterobacter cloacae and Citrobacter freundii. The migration of the latter two species in the semi‐solid medium, however, could be selectively inhibited by the incorporation of novobiocin to the medium and by incubation at 41 °C. Based on these observations, a semi‐solid enrichment medium was developed and used successfully in a Salmonella screening procedure in which a semi‐solid indicator medium was used as the first and a slide agglutination test as the second screen. Clinical laboratory evaluation of the procedure showed an increase of 92% in the frequency of positive isolations, with no false positives, as compared with a conventional multi‐step isolation procedure.
A Further Simplified Procedure for the Detection of Pseudomonas aeruginosa in Contaminated Aqueous Substrata
Authors: MOSSEL D. A. A. , VOR H. DE , EELDERINK INEKE
Published: March 2008

A simple method for the detection of Pseudomonas aeruginosa in bottled water and aqueous pharmaceutical and cosmetic preparations is described.

Subsequent to enrichment in Thom et al.'s (1971) nitrofurantoin broth at 42 °C, streaking positive cultures on to King et al.'s (1954) agar with nitrofurantoin added and incubating at 42 °C.

Stabbing colonies into single, three 2 cm layer tubes (violet red bile dextrose agar/plain agar/SIM medium) and identifying strains by their non‐fermentative attack on glucose, motility, oxidase reaction and failure to produce H2S or indole.
A Note on the Estimation of Azotobacter Densities by Membrane Filter Technique
Authors: HEGAZI N. A. , NIEMELÄ S. I.
Published: March 2008

Membrane filter technique is recommended for routine analysis of water and soil particularly those with low Azotobacter density.

Tests of four brands of membrane filters used for enumerating different groups of bacteria showed that highest Azotobacter counts were obtained with Millipore and Sartorius membranes.

Boiling of the membranes for 5 min in distilled water leads to the removal of possible substances toxic to the development of Axotobacter cells which was demonstrated by the increase of the recovered colonies, and to equal estimates obtained with the various brands.
The Effect of Tetracycline on the Coliform Gut Flora of Broiler Chickens with Special Reference to Antibiotic Resistance and O‐Serotypes of Escherichia coli
Authors: HOWE KATHERINE , LINTON A. H. , OSBORNE A. D.
Published: March 2008

The effect of terramycin, administered prophylactically in drinking water, on the gut flora of broiler birds was investigated. Exposure to the antibiotic for only 24 h profoundly affected the counts of tetracycline‐resistant strains and selected O‐serotypes carrying resistance determinants. Large numbers of Escherichia coli resistant to sulphonamides were found in treated and control birds and this is discussed in relation to the use of sulphaquinoxaline as a coccidiostat. Evidence of carcass contamination by antibiotic resistant E. coli found in the gut is presented.
Effect of Chlortetracycline Feeding on the Salmonella Reservoir in Chickens
Authors: JAROLMEN H. , SAIRK R. J. , LANGWORTH B. F.
Published: March 2008

An experimental model was developed to study the influence of antibiotic feeding on the salmonella reservoir in chickens. This model had the features of being very sensitive, allowing for the recovery of very low numbers of infecting salmonella, and, as was the case in the first experiment, closely simulated natural conditions in permitting the spread of salmonella from non‐medicated carrier birds to their penmates. The data from both experiments demonstrate clearly that feeding a sub‐therapeutic level of chlortetracycline did not increase the numbers of salmonella being shed into the environment. In fact, the salmonella pool was significantly reduced in chickens fed chlortetracycline at 200 g/ton. In the first experiment, conducted under more natural conditions, not only did the continuous use of chlortetracycline markedly reduce the spread of salmonella to a non‐inoculated population of broiler chickens but it failed to cause the emergence of chlortetracycline‐resistant salmonella. In the second experiment, where medicated feed was administered 6 days before the birds were individually infected with large numbers of salmonella, resistant organisms did appear; however these conditions did not lead to increased numbers of salmonella being shed.
An Apparatus for the Continuous Culture of Micro‐organisms on Solid Surfaces with Special Reference to Dental Plaque
Authors: DIBDIN G. H. , SHELLIS R. P. , WILSON CONSTANCE M.
Published: March 2008

In the apparatus described a multi‐channel peristaltic pump is employed to supply precisely controlled amounts of two media (saliva substitute and nutrient broth) to bacterial plaques growing on extracted teeth and other surfaces, in 6 independent chambers under identical conditions. The same pump also removes waste products. A timer‐controlled pneumatic switch programmes the delivery of medium as required. The assembly is compact and is sterilizable in a hospital autoclave as a complete unit. Surface cultures have been established following inoculation with both selected single strains and with mixed bacteria derived from saliva; in the latter instance, the bacterial deposits showed morphological resemblance to natural dental plaque.
Sugar and Polyol Permeability of Salmonella and Osmophilic Yeast Cell Membranes Measured by Turbidimetry, and its Relation to Heat Resistance
Authors: CORRY JANET E. L.
Published: March 2008

Studies of turbidity of Salmonella typhimurium 7M 4987 and of two osmophilic yeasts (Saccharomyces rouxii NCYC 381 and Schizosaccharomyces pombe NCYC 380) in solutions of sucrose, glucose, fructose, sorbitol and glycerol up to 0·5 molal indicate that the extent by which turbidity (a measure of the degree of plasmolysis) increases correlates well with the degree of protection afforded by the solutes (at higher concentration) during heating at 65·. These results support the hypothesis that degree of protection of the solutes can be correlated with degree of plasmolysis or cell shrinkage, indicating that heat resistance is associated more with dehydration of the cell than with replacement of cell water by solutes.
Mixed Inoculations with Effective and Ineffective Strains of Rhizobium leguminosarum
Authors: JOHNSTON A. W. B. , BERINGER J. E.
Published: March 2008

An ineffective Rhizobium leguminosarum strain capable of forming green nodules of similar size and number as normally effective strains was tested for its ability to compete with an effective strain in nodule formation on the pea. The ineffective strain was found to be more competitive and influenced the pattern of nodulation by the effective strain on the same root system. Nodules containing both strains were pink and able to reduce acetylene.
Bacteriological Changes Occurring During the Culture of Algae in the Liquid Phase of Animal Slurry
Authors: ALLEN MARION D. B. , GARRETT M. K.
Published: March 2008

The single‐celled alga Chlorella vulgaris was cultured in the liquid phase of pig slurry under two different light intensities, and the development of the indigenous bacterial flora was compared qualitatively and quantitatively with that of controls not inoculated with chlorella. Particular attention was given to the occurrence and survival of potential pathogens. Algal growth was found to favour the growth of certain bacteria but had little effect on or was hostile to that of others. The effects of light were mediated by the algae rather than having a direct effect on the bacterial cells. The algae, which were harvested by centrifuging and then freeze‐dried, were found to enhance the survival of certain bacteria during this procedure.
Location and Formation of Cellulases in Trichoderma viride
Authors: BERG B. , PETTERSSON G.
Published: March 2008

The location and formation of cellulases and β‐glucosidase in the fungus Trichoderma viride were studied on different substrates. The cellulases were found to be cell‐bound during active growth on cellulose, CMC, and cellobiose. On CMC, much CM‐cellulase was found cell‐free but sonication released cellulase from the washed mycelium. Analysis of the carbohydrates of the mycelial cell wall after hydrolysis revealed glucose, mannose, and galactose—the same carbohydrates as reported to be present in purified cellulase from the same organism. Glucose repressed the formation of both CM‐cellulase and Avicelase and cellobiose apparently the formation of Avicelase. Relatively little CM‐cellulase was formed on cellobiose but a straight line was obtained when a differential plot of CM‐cellulase versus protein was made.
Contamination of Pig Carcasses at Two Abattoirs by Escherichia coli with Special Reference to O‐serotypes and Antibiotic Resistance
Authors: LINTON A. H. , HANDLEY BARBARA , OSBORNE A. D. , SHAW B. G. , ROBERTS T. A. , HUDSON W. R.
Published: March 2008

Evidence of the source of carcass contamination of pigs at slaughter was obtained by determining presumptive coliform counts on faeces and on carcass surfaces, and comparing the O‐serotypes and antibiotic sensitivity patterns of Escherichia coli from both sites. All of the 16 pig carcasses from the slaughter line of a commercial abattoir were contaminated with presumptive coliform bacilli on most sites examined; the carcasses of six out of eight pigs slaughtered at the Meat Research Institute (MRI) abattoir were also contaminated, but only small numbers of coliforms could be detected on a few of the sites. The proportion of O‐serotypes of E. coli present in faeces which were also detected on carcass surfaces, indicating faecal contamination, varied between 0 and 8.6% in MRI slaughtered pigs but reached 66.6% in one group of commercially slaughtered pigs. O‐serotypes found on carcass surfaces but not in the faeces of the pigs, were used as an indication of environmental contamination and this was very evident in the commercially slaughtered pigs. A high proportion of E. coli O‐serotypes in the gut were resistant to antibiotics and these were also often found on the carcass surface and, since the range of O‐serotypes in the pig is similar to that reported in man, the pig must be considered to be a potential reservoir of antibiotic resistant E. coli for man.
The Relationship between Lactobacillus mali from Cider and Lactobacillus yamanashiensis from wine
Authors: CARR J. G. , DAVIES PATRICIA A. , DELLAGLIO F. , VESCOVO MARISA , WILLIAMS R. A. D.
Published: March 2008

The two species, Lactobacillus mali and L. yamanashiensis have been compared using the following criteria: morphological observations and biochemical tests; amino acids of the cell wall mucopeptides; % G+C ratios and DNA homology. These tests have shown these organisms to be similar but not identical. Their similarity is, however, sufficiently great to consider them as one species. Due to priority of publication L. yamanashiensis is proposed for the specific name and culture No. 239 as the type strain. All organisms previously known as L. mali will in future be called L. yamanashiensis subsp. mali since there are enough differences at a subspecies level to distinguish the wine and cider strains.
Chemical and Microbiological Studies on Leachates from a Waste Tip
Authors: RILEY R. D. , BENEDICT R. G. , SEABLOOM R. W. , CARLSON D. A.
Published: March 2008

Some chemical and microbial parameters were examined in a 12 month study of leachate from a waste tip.

Anaerobic decomposition within the tip yielded large amounts of aliphatic acids in raw leachate, which exerted a bacteriostatic action on coliforms within the tip.

Heterotrophic aerobes subcultured from the four sampling areas included representative from 11 bacterial genera and one mould.

Many of the isolated bacteria grew slowly and produced colonies much smaller than normal. The pollutants in raw leachate probably suppressed the growth of these organisms.
Determination of Relative Bacterial Levels on Carcasses and Meats—a New Quick Method
Authors: ØLGAARD K.
Published: March 2008

A new method for bacterial surface sampling meats is described. Using a cotton wool swab stick, bacteria are transferred directly to the surface of a segment (= 1/6) of an agar plate. After incubation, the number of colonies is estimated using a comparator disc, giving the result in point values of 1/3 of a log10‐unit. The average point value is then converted into the average number of colonies per segment using a Table. In order to emphasize that the results should be regarded as relative levels rather than actual bacterial counts, the result should be recorded as ‘bacteria/sample’—not ‘bacteria/cm2′.
The Effect of Soil Treatment on the Response of the Soil Microflora to the Herbicide Dalapon
Authors: WINGFIELD G. I. , DAVIES H. A. , GREAVES M. P.
Published: March 2008

Responses of the soil microflora to the herbicide dalapon have been examined using three different soil treatments. The parameters examined were bacterial numbers and dehydrogenase activity. The effects of dalapon were less marked in soil cores sprayed with dalapon than in disturbed soil samples with herbicide incorporated throughout. Air‐drying of soil reduced the rate of disappearance of dalapon. The implications of these results are discussed in relation to the problems of designing sensitive tests which avoid exaggerated or abnormal effects of the agricultural chemical under test.
Immunocytochemical Localization of Spore Specific Antigens in Ultrathin Sections
Authors: SHORT J. A. , WALKER P. D. , HINE P. , THOMSON R. O.
Published: March 2008

It has been demonstrated, using immunocytochemical techniques, that individual spore antigens are synthesized in discrete compartments of the bacterial cell. An outer layer of bacterial spores, demonstrable ultrastructurally as a distinct exosporium in Bacillus cereus or as an outer tight‐fitting sporecoat in B. subtilis, is synthesized in the cytoplasm of the mother cell. Conversely, the layers of the inner sporecoat antigens are synthesized in the forespore compartment and in association with the forespore membranes. Different layers of the sporecoat are thus synthesized in separate morphological areas and are presumably under different genetic control. Immunocytochemical techniques indicate that dipicolinic acid is found in association with the sporecore.
Techniques for the Assessment of Growth of Micro‐organisms on Plumbing Materials Used in Contact with Potable Water Supplies
Authors: BURMAN N. P. , COLBOURNE JENNIFER S.
Published: March 2008

Water samples from plumbing installations have often been of poorer microbiological quality than samples collected from the distribution main. This deterioration is often associated with a musty taste or visible turbidity in the water and slimes have sometimes been observed on water fittings. A technique to assess the ability of plumbing materials to support microbial growth is described and the most common categories of materials capable of supporting growth are identified. The most significant micro‐organisms frequently found to grow on unsuitable materials were coliform organisms, especially members of the genus Citrobacter. Aeromonas hydrophila, Pseudomonas aeruginosa and fungi.
Quasi‐contamination of a Germfree Mouse Isolator
Authors: TAYLOR D. M. , JAYNE‐WILLIAMS D. J.
Published: March 2008

Following the replacement of a damaged glove of a germfree mouse isolator, some illness and deaths occurred in the mouse colony which were considered to be possibly due to contamination.

Organisms were observed microscopically in the gut contents of the mice but repeated attempts to cultivate them proved unsuccessful.

It was finally concluded that the organisms were non‐viable, that they originated from sterlle diet, and that the deaths were due to another cause.
Observations on the In‐Vivo Growth and Symptom Production of Pseudomonas phaseolicola on Phaseolus vulgaris
Authors: RUSSELL P. E.
Published: March 2008

In vivo growth and toxin production are two separate pathogenic properties of Pseudomonas phaseolicola.
A Cylinder Template Method for Sampling Fish Surfaces
Authors: GREEN J. H. , RONSIVALLI L. J.
Published: March 2008

The method described recovers an average of four times more viable micro‐organisms from fish surfaces than the swab method.

Some advantages and disadvantages of the method are listed.
An Examination of the Effect of Three Phenolic Disinfectants on Mycobacterium tuberculosis
Authors: HEGNA IDA K.
Published: March 2008

The effect of a phenolic disinfectant (o‐phenylphenol 45% w/w) with linseed oil soap or with soya oil soap on Mycobacterium tuberculosis was determined by three methods. Neither the geometrical dilution test nor the modified capacity use‐dilution test revealed any differences between the two disinfectants. However, paradoxically both methods proved that the highest concentration of the disinfectants tested (3·5% v/v) exhibited a very low germicidal effect on M. tuberculosis, whereas lower concentrations showed a much better effect. When determining the tuberculocidal effects of various concentrations of the two disinfectants at different exposure times, the higher concentrations showed very low effects, even after the longest exposure time. At concentrations of 2·0 and 1·0% (v/v), the disinfectants displayed the most rapid effects. In the present investigation the disinfectant with the linseed oil soap seemed to destroy the cells more quickly than that with the soya oil soap. The third disinfectant containing p‐chloro‐m‐cresol and o‐benzyl‐p‐chlorophenol with a total of 9·2% (w/w) phenols in a detergent system, did not display, when employing the capacity use‐dilution test, the same phenomenon in the concentrations used, but the experiment showed that the recommended use‐dilution concentration ought to be doubled.
Effect of Yeast Extract Concentration on Viability and Cell Distortion in Rhizobium spp.
Authors: SKINNER F. A. , ROUGHLEY R. J. , CHANDLER MURIEL R.
Published: March 2008

A low concentration of yeast extract (0·1%) in liquid media favoured rapid growth and high percentage of viable cells in cultures of Rhizobium japonicum (CB 1809), R. lupini (WU 425), R. meliloti (SU 47), R. trifolii (TA1) and a cowpea strain (CB 756). Concentrations of yeast extract > 0·35% depressed viability and produced distorted cells in all strains except SU 47: TA1 was especially sensitive. When used at 0·5–1% (w/v), each yeast extract (Difco, Oxoid, Vegemite) or casein hydrolysate produced greatly enlarged abnormal cells of TA1, each containing several granules of poly‐β‐hydroxybutyrate and whorls of intracytoplasmic membranes, and showing greater internal disorganisation than that seen in root nodule bacteroids. Lysogenic and non‐lysogenic cultures of R. trifolii were all sensitive to yeast extract, and such sensitivity, for strains of several species, was unrelated to effectiveness in nodulating host plants. Glycine inhibited growth of all strains tested. Several other amino acids occurring in casein hydrolysate inhibited TA1 strongly and induced formation of distorted cells and spheroplasts; this distortion was partly counteracted by adding salts of calcium or magnesium. In media with 0·1% yeast extract the use of mannitol, sucrose, lactose or galactose as alternative carbon sources, each at a concentration of 0·02–1%, did not affect numbers of viable rhizobia or cell shape in all strains tested.
Dialysis Culture for the Production of Extracellular Protein A from Staphylococcus aureus A676
Authors: LANDWALL P.
Published: March 2008

Different nutrient media have been tested for the production of extracellular protein A from Staphylococcus aureus A676. High yields were obtained in trypticase soy broth with glucose as the main energy source. In aerated fermenter cultures the amount of protein A obtained was 0·2–0·3 gl−1, as compared to reported yields of 0·03 gl−1. Yields were further increased in dialysis cultures, where protein A concentrations of 2 gl−1. were achieved.
Isolation of a Bacteriophage of Leuconostoc mesenteroides from Dairy Products
Authors: SOZZI T. , POULIN J. M. , MARET R. , POUSAZ R.
Published: March 2008

A bacteriophage specific for the leuconostoc strain Pro2 (L. mesenteroides, group V of Garvie) was isolated from whey and buttermilk samples from two factories which use the strain Pro2 in their starters.

Morphologically, it belongs to the group B bacteriophages according to Bradley.

It is the first bacteriophage of leuconostoc isolated from dairy products. The reasons for the widespread ignorance of phages of leuconostocs are discussed.
A Rapid Method for the Detection of Non‐ionic Surfactant‐degrading Micro‐organisms
Authors: COOK K. A.
Published: March 2008

A rapid colorimetric test, involving the use of Dragendorff's reagent, has been developed for the detection of alcohol ethoxylate‐utilizing micro‐organisms on agar media. A number of putative surfactant‐utilizing bacteria were detected using this screening test and their ability to utilize surfactants was confirmed by more detailed growth studies. Suggestions are made concerning the use of this method in enumerating surfactant‐degrading micro‐organisms in natural environments.
Incidence of Enterotoxigenic Clostridium perfringens in Healthy Humans in relation to the Enhancement of Enterotoxin Production by Heat Treatment
Authors: UEMURA TAKASHI
Published: March 2008

Enterotoxin production was greatly enhanced in two of five food poisoning strains of Clostridium perfringens subjected to heat treatment prior to incubation in Duncan and Strong sporulation medium. Heating was carried out on three successive cultures of each strain, the optimum temperature for treatment being 85 °C for one strain and 95 °C for another: on each occasion cultures were heated for 20 min. The triple heat treatment procedure was used in testing strains of Cl. perfringens isolated from faeces of healthy human subjects for production of enterotoxin. Eleven of 35 (31%) individuals were found to be carriers of enterotoxigenic strains, the isolates producing more than 0·1 μ/ml of enterotoxin. Six of the 11 enterotoxigenic strains were killed by heating at 95 °C but one isolate produced more enterotoxin following treatment at this temperature than after heating at 75 °C.
Comparison of the Precision Obtained in Counting Viable Bacteria by the Spiral Plate Maker, the Droplette and the Miles & Misra Methods
Authors: HEDGES A. J. , SHANNON R. , HOBBS R. P.
Published: March 2008

The Spiral Plate Maker yielded counts of viable bacteria in pure suspensions that were at least as precise as those obtained under comparable conditions by the Droplette and Miles & Misra methods. A tendency of the Miles & Misra method to produce erroneous counts of Escherichia coli was demonstrated and the advantages of the mechanical method over established counting methods is discussed.
Ultra‐violet Treatment of Contaminated Irrigation Water and Its Effect on the Bacteriological Quality of Celery at Harvest
Authors: ROBINSON I. , ADAMS R. P.
Published: March 2008

Two crops of celery were irrigated with: (a) river water, (b) river water irradiated with ultraviolet light, or (c) mains water. Ultra‐violet radiation was effective in reducing the number of coliforms but not pectate‐degrading bacteria in the river water. At harvest, larger numbers of coliforms were found on the celery which had been irrigated with the untreated river water even when the last irrigation had been six days previously. Total colony counts and numbers of fluorescent pseudomonads and pectate‐degrading bacteria on the crop were not affected by the different water sources.
Reduction of Nitrate in a Meat System by Lactobacillus plantarum
Authors: SMITH J. L. , PALUMBO S. A.
Published: March 2008

Lactobacillus plantarum in commercial lactic acid starter cultures used to ferment meat products reduced nitrate to nitrite in sterile meat. The nitrite reacted with the meat myoglobin to yield nitrosylmyoglobin.
A Modification of Brilliant Green Agar for Improved Isolation of Salmonella
Authors: WATSON D. C. , WALKER A. P.
Published: March 2008

Five organisms commonly found to be capable of growth on commercial Brilliant Green Agar (BGA) after enrichment in Muller‐Kauffman Tetrathionate broth (MKT) were tested for sensitivity to 18 antimicrobial agents. The sensitivities of two Salmonella serotypes to these agents were also tested. A combination of sulphacetamide (at 1.0 mg/ml) and mandelic acid (at 0.25 mg/ml) incorporated into BGA was found to give maximum recovery of salmonellas from MKT broth enrichment whilst giving maximum suppression of contaminating organisms. More importantly, this Antibiotic‐enriched Brilliant Green Agar (ABG) gave a lower incidence of false positive results when compared with commercial BGA. Increasing the incubation temperature from 35 to 43°C was found to accentuate the selectivity of ABG without inhibiting the growth of salmonellas. A total of 31 Salmonella serotypes were tested for their ability to grow on ABG at 43°C; all produced typical colonies.
Inhibition of Clostridium botulinum type C by Bacteria Isolated from Mud
Authors: GRAHAM J. M.
Published: March 2008

Clostridium botulinum type C was not detected in 54 samples of mud even after seeding them with a small number of spores of this organism. From 35 of these mud samples. 108 strains of bacteria were isolated which inhibited the growth of Cl. botulinum type C. strain FH 6513, but did not denature preformed toxin. These strains fell into three groups: Bacillus spp. (73%); Gram positive non‐sporing rods (11%); and Gram positive cocci (16%). Seven strains of Bacillus spp. were further investigated and found to produce from two to five peptide antibiotics.
Effect of Ethyl Picolinate on Germination, Growth and Sporulation of Bacillus spp.
Authors: PANDEY N. K. , GOLLAKOTA K. G.
Published: March 2008

Ethyl picolinate inhibited outgrowth and sporulation of Bacillus cereus T and laboratory isolates of B. megaterium AH2 and AV1 and B. brevis AG4. The outgrowth‐inhibition was relieved by supplementing the medium before inoculation with any of the following: aspartate, asparagine, leucine, lysine, phenylalanine, tyrosine and vitamin‐free casamino acids. The uptake of radioactive precursors in the synthesis of proteins, ribonucleic acid and deoxyribonucleic acid was prevented when ethyl picolinate was added before inoculation. Cultures incubated for a short period before the addition of ethyl picolinate assimilated radioactive precursors, outgrew and divided after a lag. None of the cultures containing ethyl picolinate sporulated. Growth was not inhibited when a portion of vegetatively growing culture was transferred to medium containing ethyl picolinate.
Survival of Strains of Soft Rot Coliform Bacteria on Microthreads Exposed in the Laboratory and in the Open Air
Authors: GRAHAM D. C. , QUINN C. E. , SELLS I. ANN , HARRISON M. D.
Published: March 2008

Survival of 5 strains of the plant pathogen, Erwinia carotovora var. atroseptica and 3 strains of the plant pathogen E. carotovora var. carotovora, grown in a liquid tryptone medium and held as ‘captive’aerosols on gossamer microthreads, was determined under different atmospheric conditions in a controlled environment room and in the open air. Although these bacteria lost viability more quickly than a robust reference strain of Escherichia coli, sufficient numbers survived for 15 min or more to indicate that airborne spread of viable propagules could take place, especially under cool humid atmospheric conditions. Cells of one strain of each organism extracted from rotted potato tuber tissue were shown to behave rather like those cultured in the tryptone medium.
Effects of the Herbicide Barban and its Commercial Formulation Carbyne on Soil Micro‐organisms
Authors: QUILT P. , GROSSBARD ERNA , WRIGHT S. J. L
Published: March 2008

At high concentrations barban, its commercial formulation Carbyne or the formulating solvent, initially increased soil respiration. Increased respiration due to Carbyne or the solvent was accompanied by bacterial proliferation in response to the organic carbon of the solvent. There was no initial increase in bacterial population in barban‐treated soil. Soil respiration was inhibited after Carbyne treatment during the later stages of incubation (up to 220 days) despite a bacterial population larger than in untreated soil. Barban and Carbyne depressed the rate of glucose utilization and increased phosphatase activity in soil; it is suggested that barban interferes with the respiratory processes of soil micro‐organisms. Low concentrations (2 parts/106) of 3‐chloroaniline were detected in soil treated with either barban or Carbyne. Carbyne and its ingredients also affected the growth and physiological properties of soil bacteria and fungi.
Effects of Negative‐Charged Atmosphere on Micro‐Organisms
Authors: ROSENTHAL I. , JUVEN B. J. , GORDIN S. , BEN‐HUR E.
Published: March 2008

In an attempt to reappraise the reported interactions between ‘small negative ions’and microorganisms, it is concluded that occasional effects observed are most probably due to the mechanical removal of the cells induced by the electrical field produced by the ion generator.