bluuebunny/crossref_metadata_2025 huggingface dataset:
Measurement of Heat Resistance Parameters for Spores Isolated from Canned Products
Authors: Gibbiel A. Y. , Abd‐El Al A. T. H.
Published: March 2008

Spores of Bacillus subtilis, B. cereus, B. megaterium and B. pumilus were isolated from canned products. Heat resistance parameters were determined for these spores in distilled water and in different juices and brines. D values for B. subtilis, B. cereus, B. megaterium and B. pumilus suspended in distilled water were 1·5, 0·8, 1·6, and 1·5 min at 212°F. The D value for B. stearothermophilus in water was 3μ4 min at 248°F. Both D and Z values were reduced when spores of B. megaterium were heated in orange and mango juices. Similarly, spores of B. stearothermophilus were destroyed in okra brine faster than in water. Sodium chloride increased the thermal resistance of B. megaterium spores and this effect was independent of NaCl concentration of 2–15%. Pectin also conferred some protection against heat inactivation of spores of B. megaterium but sucrose had no effect.
Survival of Infectious Bronchitis (IB) Virus in an Iodophor Disinfectant and the Influence of Certain Components
Authors: Jordan F. T. W. , Nassar T. J.
Published: March 2008

The survival of infectious bronchitis virus in an iodophor disinfectant and modifications of the disinfectant by the omission or increase of certain components was determined by 2 methods. Both showed that iodine was the most important factor in preventing the survival of virus and that surfactant and acid were complementary to this. Stabilizer, in the presence of yeast, prolonged virus survival.
A Comparison of Two Methods for Obtaining Anaerobic Counts in Different Segments of the Gastro‐intestinal Tract of Piglets
Authors: Vervaeke I. J. , Van Nevel C. J. , Decuypere J. A. , Van Assche P. F.
Published: March 2008

Summary. The total anaerobic count on contents of the gastro‐intestinal tract of 7 piglets, fed on a milk powder diet, was determined with the ringed plates technique of Van der Heyde and the roll tube method of Hungate. Simultaneously, the oxidation‐reduction potential (Eh) was measured in the different segments. For caecal and large intestinal contents, higher counts were obtained with the roll tube method. Nevertheless, the proportional composition of the dominant flora was identical for both methods. Marked differences between the Eh of the different gastro‐intestinal segments were observed.
Studies on Freshwater Bacteria: The Effect of Enclosure in Large Experimental Tubes
Authors: Jones J. G.
Published: March 2008

Summary. A study of viable aerobic heterotrophic bacteria in the open water of Blelham Tarn and in 2 large experimental tubes introduced into the tarn, demonstrated certain differences between the populations during the period of thermal stratification. Whereas a relatively stable mixture of several species was found in the tarn, the populations of the tubes were often dominated by cycles of single species, including those from genera tentatively identified as Acinetobacter, Flavobacterium group, Moraxella, coryneform group and Aeromonas. It was not possible to be certain which factors had caused this change in the species composition, but it was noted that some nutrients, especially phosphate‐phosphorus and iron, became depleted in the tubes. The other major difference between the tarn and the experimental tubes was that complete deoxygenation of the hypolimnion was found only in the former. The bacterial populations of the tarn and the tubes were similar after overturn and during all periods when conditions were isothermal.
The Effect of Relative Humidity on the Survival of Three Serotypes of Klebsiella
Authors: Turner A. G. , Salmonsen Patricia A.
Published: March 2008

Summary. Any factor which enhances the survival of human pathogens in the hospital environment can result in increased exposure of the patient to such pathogens and perhaps contribute to an increase in patient infections. Klebsiella serotypes 3, 9 and 69 were exposed on glass to relative humidities (R.H.) of 11, 33, 53 and 85%. Death rates for all serotypes, at a constant 25°, could be correlated with the amount of moisture in the air. Prolonged survival was demonstrated at 11 and 33% R.H. with an increased death rate at 53 and 85%. The implications of this phenomenon are discussed.
A Quantitative Comparison of the Faecal Microflora of Baboons Fed a Natural Diet or a Synthetic Diet Complete or Deficient in Pyridoxine or Riboflavin
Authors: Uphill Patricia F.
Published: March 2008

Summary. Quantitative methods were used to study the microflora of faeces produced by a group of baboons receiving fresh fruit and vegetables (natural diet), and 3 groups fed a synthetic diet deficient in either pyridoxine or riboflavin, or which contained both vitamins (pair fed). There was no significant difference between the microbial counts of any of the groups of organisms studied in the pyridoxine or riboflavin deficient and pair fed baboons. Compared with baboons on natural diet, faecal counts from baboons fed the synthetic diet showed highly significant increases in Clostridium welchii and in lactose‐fermenting enterobacteria, together with a considerable decrease in the number of lactobacilli. Small increases in the numbers of micrococci, staphylococci and faecal streptococci were noted, whilst the numbers of yeasts were reduced slightly. Whilst the change from the natural to the synthetic diet caused a great alteration in the flora, the synthetic diet flora appeared to be extremely stable and generally unaffected by drastic modifications of the synthetic diet. However, marked alteration did occur on re‐feeding with the natural diet. Data on the faecal microflora of baboons are compared briefly with published data for man and other animals, and the effects of dietary changes on the composition of the faecal flora are discussed.
Identification of Pseudomonas spp. Isolated from Milk Produced in South Eastern Queensland
Authors: Juffs H. S.
Published: March 2008

Summary. Bacteria were isolated from raw and pasteurized milks produced throughout S. E. Queensland. Milk samples were plated initially on penicillin agar or on milk agar and incubated at 30° and 7°, respectively. On the basis of primary characterization, 167 of the 330 isolates obtained were identified as Pseudomonas spp. The pseudomonads were further characterized in accordance with the taxonomic studies of the genus by Stanier, Palleroni & Doudoroff (1966). Species designations were ascribed to the Pseudomonas isolates on the basis of distinctive species characteristics in conjunction with similarity coefficients between each isolate and the ideal species phenotype, as follows: Ps. fluorescens (121), Ps. aeruginosa (16), Ps. putida (12), Ps. maltophilia (9), Ps. pseudoalcaligenes (5), Ps. cepacia (3) and Ps. alcaligenes (1). A dendrogram obtained by cluster analysis of the Pseudomonas isolates is included.
An Investigation of the Oxidation‐reduction Potential and of the Effect of Oxygen on the Germination and Outgrowth of Clostridium butyricum Spores, using Platinum Electrodes
Authors: Douglas F. , Hambleton R. , Rigby G. J.
Published: March 2008

Summary. The changes in electrode potential recorded by a platinum foil electrode, and in pH, during the incubation of Clostridium butyricum spores in a medium continuously sparged with a sterile gas mixture have been correlated with the biological events occurring simultaneously. The marked fall in Eh which occurs during incubation is recorded by this type of electrode as occurring during the period of rapid cell replication; this observation may be an artefact associated with foil electrodes and the authors feel that results obtained with such electrodes should be interpreted with caution. The stimulating effect of CO2 and the increasingly inhibitory effect on germination of O2, as the concentration of the latter in the gas mixture is increased, have been noted. The inhibitory effect is thought to be due to the O2 itself and not to the high Eh produced in the medium by the O2.
Effect of Long Chain Fatty Acids on Bacterial Respiration and Amino Acid Uptake
Authors: Galbraith H. , Miller T. B.
Published: March 2008

Summary. Long chain fatty acids stimulated oxygen uptake by Gram positive bacteria at bactericidal and protoplast lytic concentrations and produced inhibition at higher levels. The order of activity between individual acids and effects of reversal agents on respiratory activity corresponded to those which produced bactericidal activity. Protoplasts were more susceptible to inhibition than whole cells. Gram negative bacteria were inhibited to a limited extent at high fatty acid concentrations, but spheroplasts were highly sensitive. Fatty acids inhibited amino acid uptake both aerobically and anaerobically at sub‐bactericidal levels. The effects were reversed by metal cations, and reflected the activity of dinitrophenol and sodium azide. The susceptibility of organisms to inhibition was of the same order as the sensitivity to other antibacterial effects. The probable mode of action of the fatty acids is discussed in terms of the interference with energy metabolism within the bacterial cell.
The L‐Phase of Erwinia carotovora var. atroseptica and its Possible Association with Plant Tissue
Authors: Jones Susan M. , Paton A. M.
Published: March 2008

Summary. The growth and recognition of the L‐phase of Erwinia carotovora var. atroseptica in vitro and in vivo is described. Evidence is offered for its existence in nature. It is postulated that the bacterium may be present in the potato plant in such a form, closely associated with the plant tissue cells, and as such may be the means of transmitting the disease from one plant to another without the disease being apparent. Under certain circumstances, as yet undetermined, changes in the environment may lead to the reversion of the L‐phase to the bacterial phase with the consequent development of the characteristic disease syndrome.
The Recovery of Indicator Bacteria on Selective Media
Authors: Hoadley A. W. , Cheng C. M.
Published: March 2008

Summary. The recovery of Pseudomonas aeruginosa, Escherichia coli, and Streptococcus faecalis from aqueous suspending media has been studied with a rich plating medium (trypticase‐soy agar) and selective media. Tap water was highly toxic to all strains investigated. Recovery of Ps. aeruginosa was most successful when phosphate buffer was the diluent. Phosphate buffer did not improve the recovery of E. coli. Streptococcus faecalis remained viable when suspended in double distilled water, deionized distilled water or phosphate buffer. Following a lag period all strains grew in 0.1% peptone water or stream water. Injury preventing recovery of viable cells on selective media occurred during suspension in all aqueous media tested, including those which supported growth. These observations suggest difficulties inherent in the interpretation of bacteriological results obtained during surveys of water sources and a need to reduce the selectivity of recovery media against injured cells.
Studies on the Mechanism of the Sporicidal Action of Glutaraldehyde
Authors: Thomas S. , Russell A. D.
Published: March 2008

Summary. Low concentrations (0.025–0.125%) of glutaraldehyde inhibited or prevented colony formation by Escherichia coli, Bacillus subtilis and B. pumilis in agar, and inhibited germination of spores of the Bacillus spp. in L‐alanine plus D‐glucose. Higher concentrations (2%) of glutaraldehyde at pH 8.5 were sporicidal. Pre‐treatment of spores with glutaraldehyde lessened release of dipicolinic acid when the spores were subsequently heated at 100°, but not at 121°. Spores treated with glutaraldehyde and then with 0.5 M thioglycollic acid in 6 M urea at 70° were less sensitive to lysis by hydrogen peroxide than spores which had not been exposed to glutaraldehyde. Glutaraldehyde was less effective in preventing peroxide induced lysis if added to spores which had been previously exposed to thioglycollic acid plus urea at 70°. The mechanism of the sporicidal activity of glutaraldehyde is discussed in relation to these findings.
Salmonella Contamination of Sheep and Mutton Carcasses Related to Pre‐slaughter Holding Conditions
Authors: Grau F. H. , Smith M. G.
Published: March 2008

Summary. When sheep were held in abattoir pens, the fleece became contaminated with salmonellae within 1 day even when there was less than 1 salmonella/g of soil. Salmonellae were first shed in the faeces after 2–3 days. Both the percentage of infected sheep and the number of salmonellae/g of faeces subsequently increased rapidly. Contamination of fleece and carcasses increased with time and with the degree to which the pens were contaminated. The fleece appeared to be a significant source of salmonella contamination of the carcass.
Nitrogen Fixation in Seawater
Authors: Wynn‐Williams D. D. , Rhodes Muriel E.
Published: March 2008

Summary. The acetylene reduction technique was used for a 3‐year period to monitor potential nitrogen fixation by aerobic heterotrophic bacteria in the sea 2 miles offshore in Cardigan Bay. Samples from depths down to 15 m were membrane‐filtered and the residues incubated aerobically or anaerobically in acetylene‐containing gas mixtures in sealed Millipore Field Monitors. Pure cultures of aerobic heterotrophs isolated from spread‐plates or monitor membranes supplied with ‘nitrogen‐free’media, were tested for ability to reduce acetylene. Glucose was the best of 14 substrates tested to support both growth and acetylene reduction by marine bacteria. The results suggested the presence of a few aerobic or facultatively anaerobic nitrogen fixers among much more numerous and efficient ‘fixed‐nitrogen‐scavengers’. The acetylene‐reducing capacity of pure cultures was inexplicably variable, even under closely‐standardized conditions: this is discussed. The more consistent acetylene reducers included various‐sized rods (Gram positive and negative), coccobacilli and yeasts, which latter may have had non‐culturable bacteria associated with them. No recognizable Azotobacter sp. was isolated, despite the strongly‐selective conditions imposed. Similar results were obtained for seawater samples from the Irish Sea and an Iceland fjord.
Cellular Changes Accompanying the Transition from Minimal to Maximal Rate of Extracellular Enzyme Secretion by Bacillus amyloliquefaciens
Authors: Stormonth D. A. , Coleman G.
Published: March 2008

Summary. During exponential growth of Bacillus amyloliquefaciens in a maltose–L‐amino acids medium at 30°, cellular protein, RNA and DNA increased in parallel. After the exponential phase, extracellular protein, including α‐amylase, was secreted into the medium at a quarter of the maximum rate of total cellular protein synthesis. The free amino acid pool for protein and the ‘nucleotide’pool for RNA both increased fourfold during the transition to the post‐exponential phase to 4.0 and 1.6%, respectively, of the cellular dry weight. Subsequently, the nucleotide pool did not change significantly whilst the free amino acid pool was reduced to 2/3 of its maximum size. When post‐exponential phase, exoprotein‐secreting bacteria were transferred to fresh culture medium, growth was re‐established and there was a 4–5 fold reduction in nucleotide pool size accompanied by a loss of exoenzyme‐forming ability.
Inhibition of Spores of Clostridium spp. by Sodium Nitrite
Authors: Roberts T. A. , Smart J. L.
Published: March 2008

Summary. Sodium nitrite heated in a laboratory medium was more inhibitory to spores of Clostridium spp. than nitrite added as a filter‐sterilized solution to the same medium. Most spores remained refractile after inhibition for >3 months and some proved viable when inoculated into fresh nitrite‐free medium. The inhibitory activity of heated nitrite medium was not stable indefinitely, growth sometimes occurred on re‐inoculation with vegetative cells.
A Technique for Sampling Micro‐organisms from the Pilo‐sebaceous Ducts
Authors: Holland K. T. , Roberts C. D. , Cunliffe W. J. , Williams M.
Published: March 2008

Summary. A method for sampling quantitatively bacteria present in the subsurface pilo‐sebaceous units of human skin is described. Less than 0.5% of a marker surface organism was isolated and counts of up to 106 organisms/cm2 obtained.
The Effect of Tetracycline upon Establishment of Escherichia coli of Bovine Origin in the Enteric Tract of Man
Authors: Hirsh D. C. , Burton Glenna C. , Blenden D. C. , Tsutakawa R.
Published: March 2008

Summary. Human volunteers were given orally 0, 50 or 1000 mg of tetracycline/day for the 4 days preceding and the 5 days following ingestion of 1–2 x 106 cells of tetracycline resistant Escherichia coli strain x‐314 of bovine origin. Of those receiving 0, 50 or 1000 mg of tetracycline/day, 9/13, 5/9 and 12/13, respectively, excreted the organism at least once during the 25‐day sampling period. Significant differences were not observed between subjects receiving 0 or 50 mg of tetracycline/day with respect to the length of time the coliform was recovered from faeces, or the maximum proportion of the total coliforms found to be E. coli x‐314. Those receiving 1000 mg of tetracycline/day shed E. coli x‐314 for longer periods and the latter's contribution to the coliform population was greater than in those subjects receiving 0 or 50 mg of tetracycline/day. It was concluded that 1000, but not 50 mg, of tetracycline/day taken orally potentiates the establishment of a tetracycline resistant E. coli in the enteric tract of man.
Bifidobacteria from the Faeces of Piglets
Authors: Zani G. , Biavati B. , Crociani F. , Matteuzzi D.
Published: March 2008

Summary. Ninety‐five strains of bifidobacteria isolated from 52 specimens of piglet faeces collected at 19 farms were studied. The main phenotypic characters of the strains were determined; however their assignment to known species of the genus Bifidobacterium was based primarily on their deoxyribonucleic acid homology relationships following DNA‐DNA hybridization tests. The majority of the strains were recognized as Bifidobacterium suis Matteuzzi et al. Some strains could not be assigned to any known species of the genus so they were allotted provisionally to 2 unassigned bacterial groups.
Effects on Plant Growth Produced by Azotobacter paspali Related to Synthesis of Plant Growth Regulating Substances
Authors: Barea J. M. , Brown Margaret E.
Published: March 2008

Summary. Treating seedling roots of several plant species with cultures of Azotobacter paspali changed plant growth and development and significantly increased weight of leaves and roots; effects were probably caused by plant growth regulators. Culture supernatant fluids contained indolyl‐3‐acetic acid, at least 3 gibberellins and 2 cytokinins. The added inoculum of A. paspali survived in plant rhizospheres for only a few weeks and no nitrogen was fixed in the root zone of young Paspalum notatum, the grass with which A. paspali is associated.
The Immunopurification of Tetanus Toxoid
Authors: Hughes M. , Thomson R. O. , Knight P. , Stephen J.
Published: March 2008

Summary. The isolation of tetanus toxoid by immunosorption chromatography is described. The immunosorbent, a polymerized horse antitoxin, was used repeatedly with little loss in capacity and recoveries of toxoid of > 90% were achieved. In terms of specific antigenic activity, immunopurified tetanus toxoid is purer than that purified by conventional procedures and is at least as immunogenic.
Competition between Food Particles and Rumen Bacteria in the Uptake of Long‐chain Fatty Acids and Triglycerides
Authors: Harfoot C. G. , Crouchman M. L. , Noble R. C. , Moore J. H.
Published: March 2008

Summary. Suspensions of mixed rumen bacteria were incubated with long‐chain fatty acids and their corresponding triglycerides in the presence and absence of the food particles present in the rumen. The uptake of free fatty acids and triglycerides by the bacteria was due largely to physical adsorption. With increasing unsaturation of the free fatty acids, less adsorption occurred and in all instances the presence of food particles reduced greatly the extent to which the fatty acids were adsorbed on the bacteria. The triglycerides were adsorbed to the bacteria to a much less extent than their corresponding free fatty acids, more of the substrate remaining in the supernatant fraction. The presence of food particles had little effect on the extent to which the triglycerides became adsorbed to the bacteria, but reduced greatly the amount of triglyceride present in the supernatant fraction. The decrease in amount of free fatty acid associated with the bacteria and the decrease in the amount of triglyceride in the supernatant liquid when food particles were present, was wholly accounted for by the increase in amount of these substrates associated with the food particles. The implications of these findings with respect to the metabolism of lipids in the rumen is discussed.
Microbiology of Nigerian Palm Wine with Particular Reference to Bacteria
Authors: OKAFOR N.
Published: March 2008

The bacteria isolated from samples of wine produced by the fermentation of the saps of Elaeis and Raphia palms were identified as Micrococcus, Leuconostoc, Streptococcus, Lactobacillus, Acetobacter, Serratia, Aerobacter (Klebsiella), Bacillus, Zymomonas and Brevibacterium. The organisms occurring most frequently belonged to the first 5 genera. The change from c. pH 7 to c. pH 4.5 during fermentation appeared to be due to lactic acid bacteria and/or certain Gram negative bacteria, e.g. Serratia and Aerobacter (Klebsiella) spp. From about the 3rd day onwards, Acetobacter spp. were recovered.
Nutritional Requirements for Growth and Sporulation of Clostridium perfringens
Authors: MUHAMMED S. I. , MORRISON S. M. , BOYD W. L.
Published: March 2008

Two strains of Clostridium perfringens grew in a chemically defined medium consisting of L‐tryptophan, L‐arginine, L‐glutamic acid, L‐histidine HCl, L‐leucine, DL‐threonine, DL‐phenylalanine, DL‐tryrosine, DL‐valine, L‐cystine, ascorbic acid, Ca d‐pantothenate, pyridoxine, biotin, adenine HCl, glucose, salts and mercaptoacetic acid. Alanine, aspartic acid and methionine were highly stimulatory but not essential for growth. Growth did not occur in the absence of glucose, but other fermentable carbohydrates were not tested. Acetone, isopropyl alcohol, succinic acid, acetic acid, butanol, butyric acid, lactic acid, pyruvic acid, oxaloacetic acid or acetaldehyde did not eliminate the requirement for glucose. Methionine was required for sporulation; one strain also required riboflavin, isoleucine, serine and lysine. Butanol increased the degree of sporulation in a complex thioglycolate medium. Failure of Cl. perfringens to sporulate in inadequately buffered media containing glucose was shown to be caused by the high H‐ion concentration developing in the culture medium. In addition, some possible end‐products of glucose metabolism such as lactic acid, oxaloacetic acid and acetaldehyde, reduced sporulation in one strain appreciably.
The Effects of Feeding Tetracycline, Nitrovin and Quindoxin on the Drug‐Resistance of Coli‐aerogenes Bacteria from Calves and Pigs
Authors: LINTON A. H. , HOWE KATHERINE , OSBORNE A. D.
Published: March 2008

A study of calves and pigs was made to compare the effects on intestinal coli‐aerogenes bacteria of feeding diets medicated with tetracycline, nitrovin or quindoxin. Results showed that even before the introduction of medicated diets, drug‐resistant coli‐aerogenes bacteria were present in surprisingly high numbers. However, it was clear with both animal species that only tetracycline had a selective effect. With calves a resistance to furazolidone was frequently present in tetracycline‐resistant organisms. Analysis of the resistance patterns supported the contention that the dominant coli‐aerogenes bacteria in the gut flora following use of certain growth‐promoters, resulted from suppression of fully sensitive organisms: the distribution of the various resistance patterns was independent of the agent used and whether or not the diet was medicated. There was no significant difference in the trans‐missibility of resistance genes between calves and pigs receiving either tetracycline or quindoxin or neither treatment. Results obtained with nitrovin were thought to be similar but, inexplicably, the control animals all gave low values.
The Effect of Sporulation Temperature on the Resistance of Bacillus subtilis to a Chemical Inhibitor
Authors: BELL N. D. S. , PARKER M. S.
Published: March 2008

The ability of spores of Bacillus subtilis to germinate at 50° in sublethal concentrations of chlorocresol is related to sporulation temperature as is the resistance of the subsequent outgrowth at 50° to this substance. The degree of germination, age of spores and amount of outgrowth produced are of minor importance in determining resistance of the outgrowth.
Synergism between Ultrasonic Waves and Hydrogen Peroxide in the Killing of Micro‐organisms
Authors: AHMED F. I. K. , RUSSELL C.
Published: March 2008

The lethal effect on different micro‐organisms of ultrasonic waves and hydrogen peroxide separately and in combination was examined. Ultrasonic waves were able to disintegrate Fusobacterium nucleatum within 3 min and to kill Veillonella parvula after 15 min and Streptoccus sanguis after 20 min; 20 vols H2O2 (6% w/v) killed V. parvula, Strep. sanguis and Staphylococcus aureus after 5 min treatment, and Clostridium sporogenes spores after 25 min. Sonication of Cl. sporogenes spores, Bacillus cereus spores and Candida albicans in 20 vols H2O2, using an ultrasonic probe, was lethal to the organisms after 15, 10 and 10 min, respectively. The latter 2 organisms were not killed by 30 min exposure to either agent separately. Similar results were obtained when an ultrasonic tank was used for sonication.
Studies of Different Sampling Methods for the Determination of Bacterial Counts from Frozen Broilers
Authors: NOTERMANS S. , KAMPELMACHER E. H. , VAN SCHOTHORST M.
Published: March 2008

The attachment of bacteria to the skin of broilers was not influenced by freezing or thawing of the carcasses. Only a small proportion of indicator organisms which were attached to the skin during processing were recovered in either the thaw water or rinsing fluid; a close correlation was found between bacterial counts from both types of sample. Numbers of Enterobacteriaceae and total counts were readily obtained by sampling the thaw water and this is, moreover, a non‐destructive method. In order to detect the presence or absence of pathogenic micro‐organisms the rinsing method was considered to be preferable, provided that the whole of the rinsing fluid was tested in each case.
Toxicity of Sodium and Chloride Ions to Rhizobium spp. in Broth and Peat Culture
Authors: STEINBORN JULIA , ROUGHLEY R. J.
Published: March 2008

The growth of a strain of Rhizobium trifolii and of R. meliloti was studied in broth and peat cultures to determine the relative toxicity of Na+ and Cl‐. The following salts were added in a range of concentrations: Na2HPO4 as a source of Na+, CaCl2.2H2O as a source of Cl‐, and NaCl. Disodium hydrogen orthophosphate affected the growth rate of both strains in broth culture but not in peat culture. Unexpectedly, calcium chloride was more toxic than NaCl in broth and peat culture. The toxicity of NaCl can be ascribed to the Cl‐. Rhizobium meliloti strains grew on 3·5% NaCl after adaptation during a long period. Rhizobia for soya bean and cowpea grew at 0·5% NaCl and those for clover and pea, at 1·0% NaCl.
A Comparison of Various Selective Isolation Media for their Efficiency in the Diagnosis and Enumeration of Soft Rot Coliform Bacteria
Authors: O'NEILL R. , LOGAN C.
Published: March 2008

The efficiency of various selective isolation media for diagnosis and enumeration of Erwinia carotovora var. atroseptica is described. In both pure culture and mixed population studies the medium of choice is that of Cuppels and Kelman's modified by the addition of manganous sulphate. Difficulties in the preparation of this pectate medium have been overcome by including an antifoam agent.
Effects of Poorly Metabolized Hydrocarbons on Substrate Oxidation by Cladosporium resinae
Authors: WALKER J. D. , COONEY J. J.
Published: March 2008

Twelve hydrocarbons which singly support no growth or little growth of Cladosporium resinae were examined for their effects on utilization of four substrates which do support growth of the fungus. Of the 48 combinations of an oxidizable substrate with a potential hydrocarbon substrate, 8 combinations supported increased oxygen consumption above the level obtained with the oxidizable substrate alone. There was no evidence of co‐oxidation of the potential co‐substrates toluene or p‐xylene; their effects on increasing O2‐uptake appear to be due to permeability changes. With hexadecane alone, the ratio hexadecane oxidized to CO2: hexadecane taken up by cells was 97:3. Addition of p‐xylene or toluene decreased that ratio slightly to 96:4 and 89:11, respectively. These high ratios of hydrocarbon oxidized to hydrocarbon taken up may be advantageous during degradation of petroleum in the natural environment, since petroleum components could be degraded without formation of a large biomass.
MacConkey and Glutamate Media in the Bacteriological Examination of Seawater
Authors: ALIVISATOS G. P. , PAPADAKIS J. A.
Published: March 2008

Confirmatory tests were made in 4807 positive tubes of MacConkey broth. It was found that when an equal volume of seawater was added to a double strength MacConkey broth only 88% of the tubes contained coliform organisms (12% false‐positive reactions); when, however, the ratio of the volume of seawater to broth was 1/5 or less, coliform organisms were found in 93·5% of the positive tubes (6·5% false‐positive reactions). Glutamate medium gives a higher rate of false reactions than MacConkey broth when an equal volume of seawater is added to double strength medium. When the volume ratio of seawater to glutamate medium is equal to or less than 1/5, then the minerals‐modified lactose glutamate medium gives better results than MacConkey broth in the coliform and especially in the Escherichia coli count. The difference is statistically significant.

It is thus concluded that for the bacteriological examination of seawater the volume ratio of water to medium should be 1/5 or less and also that glutamate medium is the medium of choice.
Degradation of Microbicides under Different Environmental Conditions
Authors: VOETS J. P. , PIPYN P. , VAN LANCKER P. , VERSTRAETE W.
Published: March 2008

To determine the biodegradability of some widely used microbicides, these products were dissolved in a mineral solution and synthetic sewage and their breakdown was followed under aerobic and anaerobic conditions. The results indicated that most biocides will not raise pollution problems provided they are discharged into domestic sewage and subsequently treated by aerobic water purification systems. However, all but a few of the biocides tested failed to be degraded in tests simulating conditions prevailing in oligotrophic aquatic systems or in anaerobic ecosystems.
Cell Envelopes of Gram negative Bacteria: Composition, Response to Chelating Agents and Susceptibility of Whole Cells to Antibacterial Agents
Authors: HAQUE H. , RUSSELL A. D.
Published: March 2008

The effects of ethylenediamine tetraacetic acid (EDTA) and related chelating agents on the sensitivity of isolated cell envelopes of some β‐lactamase +ve and ‐ve strains of Gram negative bacteria have been investigated. Envelopes from Pseudomonas aeruginosa (especially strain NCTC 1999) contained the greatest amounts of Mg2+ and were the most sensitive to these agents in terms of (i) lysis, (ii) release of cations, (iii) release of readily extractable lipid. Cyclohexane—1,2, ‐diamine‐tetraacetic acid was the most effective chelator, followed by EDTA and N‐hydroxy‐ethylethylenediamine triacetic acid, with nitriloacetic acid and iminodiacetic acid having little effect. A lysozyme–Tris–EDTA system also caused lysis of P. aeruginosa envelopes. The sensitivity of whole cells of the various strains to some β‐lactam antibiotics and other antibacterial agents has been carried out and the basis of sensitivity or resistance in relation to drug destruction and the above envelope composition discussed.
An Indirect Radiolabelled Antibody Staining Technique for the Rapid Detection and Identification of Bacteria
Authors: BENBOUGH J. E. , MARTIN K. L.
Published: March 2008

Small numbers of Bacillus subtilis var. niger spores, Serratia marcescens and Francisella tularensis can be detected and identified in an hour using an indirect radiolabelled antibody staining technique with homologous rabbit antibacterial antibody and radiolabelled goat anti‐rabbit globulin. Tritium is better than 125I, 14C and 35S for labelling the globulin. The reagent obtained is sensitive and adequately stable.
Copper and Iron as Determinant Factors of Antibiotic Production by Pseudomonas reptilivora
Authors: MARTINEZ‐MOLINA E. , RIO L. A. DEL , OLIVARES J.
Published: March 2008

Production by Pseudomonas reptilivora of three antibiotics, named A, B1 and B2, took place in media containing either an inorganic or organic nitrogen source but only in the presence of available copper and iron. Higher yields were obtained in media containing inorganic nitrogen. Antibiotic synthesis was mediated by definite levels of copper and iron which determined the production of (a) the iron and copper‐dependent activity A, (b) the two copper‐dependent activities B1 and B2, or (c) a mixture of the three.
Pectinase Production by Bacteria Associated with Improved Preservative Permeability in Sitka Spruce: Synthesis and Secretion of Polygalacturonate Lyase by Cytophaga johnsonii
Authors: KUROWSKI W. M. , DUNLEAVY J. A.
Published: March 2008

Cytophaga johnsonii synthesized a polygalacturonate lyase which produced random cleavage of galacturonic acid polymers. No pectin methyl‐esterase or hydrolytic pectinase activities could be detected in cultures of the organism. Polygalacturonate lyase synthesis was inducible and also subject to repression by glucose and other compounds. Galacturonic acid was the most effective inducer; lower activities were obtained with citrus pectin, polygalacturonic and polypectic acids. Glucose repression of lyase synthesis was not alleviated by 5 mM‐adenosine‐3′.5′‐cyclic‐monophosphate. Enzyme production was growth‐linked and ceased when batch cultures entered the stationary phase. In steady‐state chemostat cultures lyase activity was maximal at a dilution rate (D) of 0.19 h‐1. Polygalacturonate lyase was both cell‐bound and free in the supernatant medium. The proportion of free enzyme increased throughout the batch growth cycle and in chemostat cultures over 70% of the activity was cell free at dilution rates below 0.05 h‐1.
Antibiotic Residues and Their Recovery from Animal Tissues
Authors: McCRACKEN ANN , O'BRIEN J. J. , CAMPBELL N.
Published: March 2008

Investigations were carried out to detect antibiotics in the presence of animal tissues. It was found that antibiotic levels below the maximum permissible level suggested for meat by the F.A.O./W.H.O. could be detected. Tissue samples from animals injected with an antibiotic were examined and results compared with meat to which antibiotic had been added
Ultrasonication—An Enrichment Technique for Microcyst‐forming Bacteria
Authors: SUTHERLAND I. W.
Published: March 2008

Brief ultrasonic treatment of samples of bark, soil or water containing fruiting myxobacteria yields higher isolation rates than conventional procedures when aliquots are applied to solid media. Many normal contaminants, including nematodes, are destroyed and representative strains of most genera of Myxobacteria and Sporocytophaga have been isolated in this way. The technique can also be applied to the isolation of cyst‐forming Azotobacter spp. and may be suitable for cyst‐forming Methanobacterium spp. A further application is in the comparison of bacillary and resting forms in natural environments.
Application of Flow Microcalorimetry to Analytical Problems: the Preparation, Storage and Assay of Frozen Inocula of Saccharomyces cerevisiae
Authors: BEEZER A. E. , NEWELL R. D. , TYRRELL H. J. V.
Published: March 2008

A simple procedure for the freezing of large batches of yeast inocula (up to 150 samples) for storage at liquid nitrogen temperatures with the retention of high viability after thawing is described. The recovered frozen cells were examined using a flow microcalorimetric procedure which enables a rapid determination of viability. The application of such inocula to antibiotic assays and growth studies is discussed.
Isolation of a Mycoplasma sp. (Group 7) Previously Associated with Cattle from Guinea Pigs’Genital Tracts
Authors: RIGBY CHARLOTTE , LANGFORD E. V.
Published: March 2008

The incidence and persistence of genital mycoplasmas of 25 normal guinea pigs were investigated by culturing swabs collected over a 63‐day period. Mycoplasmas were consistently isolated from two of the five males, but only once each from three of the 20 females. The 16 strains isolated were divided into four groups. Representative strains of one group were identified as Mycoplasma sp. (group 7 of Leach 1973), by growth inhibition, growth precipitation and fluorescent antibody tests. The other groups were provisionally classified as Mycoplasma spp. and an Acholeplasma sp.
Resistance to Inorganic Salts and Antibiotics Among Sewage‐borne Enterobacteriaceae and Achromobacteriaceae
Authors: VARMA M. M. , THOMAS W. A. , PRASAD C.
Published: March 2008

Lead‐resistant bacteria isolated from domestic sewage showed simultaneous resistance to other inorganic metals and also antibiotics.
Rapid Confirmation of Suspect Salmonella Colonies by Use of the Minitek System in Conjunction with Serological Tests
Authors: COX N. A. , MERCURI A. J.
Published: March 2008

Colonies of 40 members of the Enterobacteriaceae family (26 Salmonella serotypes and 14 other organisms) were picked from selective agar plates and inoculated into Minitek inoculum broth (BBL) and then onto Minitek discs of dextrose, lactose, sucrose, mannitol, maltose, dulcitol, lysine and H2S. After incubation for 6 h, the inoculum broth was tested with salmonella Poly O and after 24 h with salmonella Poly H antisera. The results of the biochemical tests were read after 24 h incubation. With this procedure, all the salmonella cultures used in this study were confirmed as salmonella and differentiated from all the other organisms, which were rejected. This procedure provides an alternative to the time consuming conventional procedures for the biochemical and serological confirmation of suspect salmonella colonies on selective agar plates.
Possible Cause of Anomalies in the Oxidation‐Fermentation Test
Authors: ANDREWS A. R.
Published: March 2008

It has been shown that oxygen can diffuse through oils used as sealants in the Oxidation—Fermentation test.

Vaseline was shown to be the only satisfactory sealant.
Effect of Temperature and Added Polyphosphate on the Survival of Salmonellae in Poultry Meat during Cold Storage
Authors: FOSTER R. D. , MEAD G. C.
Published: March 2008

The behaviour of five salmonella serotypes in minced chicken breast (pH 5.8) and leg muscle (pH 6.4) held at 1 °C, ‐2 °C, ‐5 °C and ‐20 °C was studied with and without the addition of 0.35% polyphosphate (Puron 604).

In the absence of polyphosphate, survival of the test organisms was greater in breast than in leg muscle at all four temperatures, but was greatest at ‐20 °C in both types of muscle and least at ‐2 °C and ‐5 °C, just above and below the freezing point of the muscle.

Addition of polyphosphate increased the death rate of the salmonellae in breast muscle held at ‐2 °C and to a lesser extent at ‐20 °C but had little or no effect in leg muscle or in breast held at 1 °C or ‐5 °C.
Production of Plant Growth Regulators by Rhizosphere Phosphate‐solubilizing Bacteria
Authors: BAREA J. M. , NAVARRO E. , MONTOYA E.
Published: March 2008

Culture supernatant fluids of 50 phosphate‐dissolving bacteria isolated from rhizospheres of crop plants were examined for IAA, gibberellins and cytokinins. These bacteria possessed phytase activity and 27 could dissolve rock phosphate. Twenty bacteria synthesized all 3 types of plant hormones, 43 produced IAA, 29 formed gibberellins and 45 cultures produced cytokinin‐like substances. Of the 50 bacteria tested 28 decomposed IAA. Plant growth inhibitors were detected in cultures of some isolates. The ecological significance of these rhizosphere bacteria and their mode of action when used as inoculants is considered.
The Characterization of Clinically Important Gram Negative Anaerobic Bacilli by Conventional Bacteriological Tests
Authors: DUERDEN B. I. , HOLBROOK W. P. , COLLEE J. G. , WATT B.
Published: March 2008

One hundred and sixty‐five reference strains and laboratory isolates of Gram negative, non‐sporing, anaerobic bacilli were subjected to a series of simple laboratory tests that were initially selected for their discriminatory value. Conventional biochemical tests, tests of resistance to antibiotics, and tolerance to dyes and bile salts were included. These tests allowed a clear separation of strains into three main groups: Bacteroides fragilis, B. melaninogenicus and Fusobacterium spp. Certain tests were found useful for identifying recognized subspecies of B. fragilis and B. melaninogenicus. A scheme for the identification of unknown laboratory isolates of Gram negative anaerobic bacilli is presented.
The Application of Miniaturized Methods for the Characterization of Various Organisms Isolated from the Animal Gut
Authors: JAYNE‐WILLIAMS D. J.
Published: March 2008

Miniaturized methods for the characterization of streptococci, lactobacilli and aerobic Gram negative rods are described and the results obtained with 461 cultures from the calf rumen and quail gut tabulated. The methods afford a considerable saving in time and materials without concomitant loss of accuracy.
The Fate of Benzothiazole‐2‐Sulphonic Acid in Biologically Treated Industrial Effluents
Authors: MAINPRIZE J. , KNAPP J. S. , CALLELY A. G.
Published: March 2008

Benzothiazole‐2‐sulphonic acid is capable of being completely degraded by micro‐organisms, though in this study, all attempts to isolate a pure culture capable of growing in a liquid benzothiazole‐2‐sulphonic acid–mineral‐salts medium were unsuccessful. Both the mixed culture which was capable of growing in this medium and sludge from an activated sludge plant treating an influent containing benzothiazole‐2‐sulphonic acid, would also oxidize benzothiazole, 2‐hydroxybenzothiazole and 2‐mercaptobenzothiazole. The sulphur and nitrogen originally present in benzothiazole‐2‐sulphonic acid were quantitatively converted to sulphate and ammonia, respectively. Die‐away tests indicate that benzothiazole‐2‐sulphonic acid was only immediately degraded by populations which previously had been exposed to this compound.
Some Properties of the Lipase of Geotrichum candidum Evaluated by a Fluorimetric Assay Technique
Authors: DOOIJEWAARD‐KLOOSTERZIEL ADRIANA M. P. , WOUTERS J. T. M.
Published: March 2008

The oleic acid ester of 4‐methylumbelliferone was found to be a suitable substrate for the fluorimetric assay of the lipase of Geotrichum candidum. This substrate spontaneously formed an emulsion in the assay mixture and had a Km of 10·3 μM. The fluorimetric method was at least a thousand times more sensitive than the conventional potentiometric method. The lower limit of sensitivity of the assay was 1 nmole fatty acid released per min. Optimum conditions for detection of lipase in the culture filtrate of G. candidum were devised. The influence of pH, Ca2+ and several other factors were investigated.
A Simplified Method for the Isolation of Bacteroides nodusus from Ovine Foot‐rot and Studies on its Colony Morphology and Serology
Authors: THORLEY C. M.
Published: March 2008

A simple method for the isolation of Bacteroides nodosus from foot‐rot lesions in sheep is described together with observations on the colony morphology of freshly isolated strains and variant colonies arising on subculture in the laboratory. Serological results from a study of English isolates demonstrate a multiplicity of types based on the K antigens as well as additional antigens common to all strains.
A Longitudinal Study of Escherichia coli in Cows and Calves with Special Reference to the Distribution of O‐antigen Types and Antibiotic Resistance
Authors: HOWE KATHERINE , LINTON A.H. , OSBORNE A. D.
Published: March 2008

The faecal excretion of E. coli from 6 adult cows was followed over a period of 105 days. E. coli were excreted in only 23·4% of specimens and the patterns of excretion varied between animals. All isolates of E. coli were antibiotic sensitive and fell into 6 O‐antigen types; very few were non‐typeable. The O‐types excreted by each animal, compared with those from other cows in the same house, were traced with time. A similar but less intense study was undertaken in 8 calves. In contrast E. coli was excreted from all samples and included both antibiotic sensitive and resistant strains; 37 O‐types were represented. The persistence of specific O‐types within each calf and their spread to other calves in the same house were studied. A comparison of the O‐types in the bovine species with those isolated from man has been made.
Role of Azotobacter paspali in Association with Paspalum notatum
Authors: BROWN MARGARET E.
Published: March 2008

Azotobacter paspali grows in the rhizospheres of Paspalum notatum where it is thought to fix nitrogen actively and hence improve pasture growth. In the experiments described here A. paspali improved growth primarily by producing growth regulating substances. Nitrogenase activity was not detected in rhizospheres of young plants. Its occurrence in older plants was not necessarily associated with the presence of A. paspali and was greater in the rhizopheres of control than of inoculated plants.
Dextranase Activity in Oerskovia xanthineolytica
Authors: HAYWARD A. C. , SLY L. I.
Published: March 2008

Two isolates of a nocardioform bacterium capable of producing an extracellular hydrolase for high molecular weight dextran were isolated from soil by selection of active colonies on a blue dextran agar medium. Comparison with the type strains of Oerskovia turbata and O. xanthineolytica showed that these fresh isolates were closely similar to the latter species. Extracellular dextranase activity was not detected in the type strains of Oerskovia spp. or in 78 other Gram positive bacteria representing 58 species and 14 genera.
The Longevity of Thermoactinomycete Endospores in Natural Substrates
Authors: UNSWORTH BRIDGET A. , CROSS T. , SEAWARD M. R. D. , SIMS R. E.
Published: March 2008

Occupational debris from beneath the Roman fort Vindolanda, and lake sediments cored from Seamere in East Anglia were examined for the presence of viable Thermoactinomyces endospores. Up to 104 viable endospores/g dry wt were recovered from the occupational debris at Vindolanda deposited between 1850 to 1890 years ago. Highest numbers were found in layers of bracken and straw litter sandwiched between clay floors within a military building. Associated artefacts and writing tablets have been used to date the various layers. Pollen analyses on core samples from Seamere revealed one region containing a declining percentage of tree pollen and the appearance of cereal and associated weed pollens suggesting the presence of a primitive agricultural community on the shores of the lake. Samples from this section of the core, deposited ca. 1950 to 2750 years ago, contained viable thermoactinomycete endospores. These studies confirm the extreme longevity of Thermoactinomycete endospores and suggest that these organisms may be usefully employed in future archaeological and palaeoecological studies.