bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Study of Rapid and Simplified Confirmatory Tests for Clostridium perfringens
Authors: MEAD G. C. , LEÓN LUCY PÁEZ DE , ADAMS B. W. 
Published: March 2008

Strains of Clostridium perfringens and culturally similar species which also may grow on selective isolation media for this organism were examined by conventional confirmatory tests, the API ZYM system and by individual tests for phosphatase and glutamic acid decarboxylase activity.API ZYM tests, involving 19 different enzymes, confirmed the known similarity between Cl. perfringens, Cl. absonum, Cl. paraperfringens and Cl. sardiniensis but effectively distinguished this group from Cl. bifermentans, Cl. celatum, Cl. perenne and Cl. sordellii. A similar separation was achieved by a single test for acid phosphatase which could be applied to individual colonies on a plating medium.Because the acid phosphatase test was found to be of greater value than nitrate reduction in distinguishing Cl. perfringens, it could replace the latter in the usual series of confirmatory tests. It is suggested that strains from Cl. perfringens isolation media should be screened for acid phosphatase activity at the purification stage and only positive strains subjected to further tests.It was found that Cl. perfringens could not be distinguished from the other species on the basis of glutamate decarboxylase activity.
An Electrophoretic Analysis of Variation in the Glucose‐6‐Phosphate Dehydrogenase and Malate Dehydrogenase of Vibrio cholerae, Vibrio parahaemolyticus and Vibrio fluvialis
Authors: MOMEN H. , SALLES C. A. 
Published: March 2008

A total of 59 isolates of Vibrio cholerae, V. parahaemolyticus and V. fluvialis were studied using the techniques of enzyme electrophoresis. The enzymes used were malate dehydrogenase (E.C.I. 1.1.37) and glucose‐6‐phospate dehydrogenase (E.C.I. 1.1.49). The results in general confirmed classical methods of vibrio taxonomy. The three species could be separated from each other and identified by their enzyme variant types.The term zymovar, a group of strains having similar enzyme variants, is introduced. In the V. cholerae isolates six zymovars were found. All V. cholerae serovar 01 strains were classified in the same zymovar except for some strains of environmental origin, which occurred in another zymovar. In V. fluvialis two zymovars were detected corresponding with biovars 1 and 2 of this organism. All isolates of V. parahaemolyticus gave the same enzyme type.The technique of enzyme electrophoresis appears to be a useful tool in vibrio taxonomy and used in conjunction with other methods may aid in the elucidation of the systematics of the genus.
The Potassium Iodide Method for Determining Protection Factors in Open‐fronted Microbiological Safety Cabinets
Authors: CLARK R. P. , GOFF M. R. 
Published: March 2008

A method for determining operator protection factors in Class I and Class II microbiological safety cabinets and for evaluating product protection factors in Class II cabinets, is described. The technique employs an aerosol of potassium iodide droplets produced by a spinning disc generator together with special centripetal air samplers detecting any aerosol escape. The method meets the requirements of British Standard (BS) 5726 and is an alternative to the microbiological technique.The method has been used to evaluate the performance of a number of safety cabinets in relation to the requirements of BS 5726.Working procedures and unsuitable environments have been shown to prejudice the containment performance of open‐fronted cabinets by several orders of magnitude.The relationship between inflow air velocity and protection factors in Class I safety cabinets has confirmed the optimum requirements defined in the British Standard.
The occurrence and properties of Gemmiger formicilis and related anaerobic budding bacteria in the avian caecum
Authors: Croucher Susan C. , Barnes Ella M. 
Published: March 2008

Gram negative budding bacteria with a characteristic morphology have been observed in the caeca of chickens, turkeys, ducks and guinea fowl at levels between 0–4 and 24% of the total flora. Using strict anaerobic techniques a detailed study has been made of the organisms isolated from the caeca of chickens aged between 15 and 44 d. The majority of isolates were identified as Gemmiger formicilis, the strains being divided into twomajor types according to the relative amounts of butyric acid and lactic acid produced from glucose. A second group of isolates could not be related to any known species.Amongst properties of ecological interest studied were limiting temperatures for growth, ammonia utilization, ability to utilize various carbon sources and survival in environments outside the intestine.Attempts to produce a selective medium for the isolation of these organisms when present at less than 2% of the total flora were unsuccessful.
The Rappaport—Vassiliadis (RV) enrichment medium for the isolation of salmonellas: An overview
Authors: Vassiliadis P. 
Published: March 2008

In 1976 two major modifications were introduced in the composition and use of Rappaport's magnesium chloride—malachite green enrichment medium for salmonellas. One modification consisted of the reduction to one‐third of the amount of malachite green contained in the original formulation of Rappaport's medium, and the other in the incubation at 43 instead of 37°C. Since 1980, the modified medium incubated at 43°C is known as RV (Rappaport—Vassiliadis) enrichment medium for salmonellas.From 1977 to 1981, in eleven studies, the RV enrichment broth has been compared to the standardized Muller‐Kauffmann tetrathionate broth (MK broth) recommended as a reference method by the International Standards Organization, for the isolation of salmonellas from meat products, after pre‐enrichment in buffered peptone water. In all these studies the RV broth was superior to the MK broth in the isolation of salmonellas from naturally contaminated meat products (bovine minced meat, pork sausages, mesenteric lymph nodes, chicken carcases), sewage and faeces of healthy pigs, after pre‐enrichment in buffered peptone water. This superiority was statistically significant in seven of the eleven trials. Furthermore, in three more investigations the RV medium was compared with Oxoid selenite broth, with Difco tetrathionate broth and Difco selenite‐cystine broth. In all these three investigations the RV medium was superior for isolation of salmonellas, after pre‐enrichment, from naturally contaminated meat products and animal feeds. The superiority was statistically highly significant.When dealing with meat products, the RV medium in 10 ml volume inoculated with 0.1 ml of the pre‐enrichment medium, proved to be as effective as the RV medium in 100 ml volume, inoculated with 1 ml of pre‐enrichment medium, and clearly superior to the MK broth in 100 ml quantity.In all these studies involving enrichment in RV medium, MK broth, Difco tetrathionate broth, Oxoid selenite broth, incubated at 43°C and Difco selenite‐cystine broth incubated at 37°C, the RV medium proved to be highly specific. This means that the RV medium inhibits much more strongly the competing organisms, (including ‘Proteus hauseri’) which are lactose‐ and sucrose‐negative on the selective media and which may produce salmonella‐like colonies.
Quality assurance of selective culture media for bacteria, moulds and yeasts: an attempt at standardization at the international level
Authors: Mossel D.A.A. , Laarhoven Trees M.G. Bonants‐Van , Ligtenberg‐Merkus Anniek M.Th. , Werdler Maria E.B. 
Published: March 2008

To facilitate monitoring of culture media, a simple quantitative streaking technique, implying ever‐decreasing numbers of colony‐forming units per surface area, as in spiral plating, was developed. The procedure evaluates, in quantitative terms, the ability of media (1) to support the formation of colonies by organisms that it was designed to grow and (2) to resist colonization by organisms that it is expected to suppress. The procedure was therefore termed ecometric evaluation. The ecometric results appeared to agree well with observations made on productivity and selectivity of the media studied during routine examination of specimens.These encouraging results prompted further, rigorous standardization of ecometry. A template was developed to standardize inoculation and the depth of the agar was controlled to within ± 10%. Finally the attributes of the inocula used were accurately defined.The standardized ecometric technique has been found useful for the following purposes: (1) to assess the practical significance of the inhibitory effect of gentamicin observed in some moulds and yeasts (this was solved by replacing poorer basal media by one particular richer modification, viz. yeast morphology agar); (2) the development of a blood‐free selective enumeration medium for Campylobacter jejuni, i.e. sulphide iron motility agar plus the combination of antibiotics suggested by Skirrow (1977); and (3) verification of the absence of antimicrobial activity of enzyme preparations, e.g. catalase, used in culture media to remedy sublethal damage in certain groups of bacteria.Ecometric evaluation can now be recommended for (1) routine monitoring of consignments of dehydrated or ready‐to‐use, purchased media; and (2) in‐house checking of the functioning of medium preparation departments. Only occasionally is it necessary to use conventional counting techniques to confirm the results.
The effect of yoghurt on some components of the gut microflora and on the metabolism of lactose in the rat
Authors: Garvie Ellen I. , Cole C.B. , Fuller R. , Hewitt D. 
Published: March 2008

Garvie, E.I. Cole, C.B., Fuller, R. & Hewitt, D. 1984. The effect of yoghurt on some components of the gut microflora and on the metabolism of lactose in the rat. Journal of Applied Bacteriology56, 237–245Feeding yoghurt or base milk (from which the yoghurt was prepared by fermentation) to rats increased the counts of coliforms in the gut whereas the counts of lactobacilli were reduced by yoghurt but not by the base milk. Lactobacillus bulgaricus survived in the guts of gnotobiotic and conventional rats when yoghurt was fed continuously. Streptococcus thermophilus also survived in gnotobiotic rats but its ability to survive in conventional rats could not be examined. Both organisms failed to colonise the gut when a small inoculum of yoghurt was administered orally to germfree rats maintained on the stock diet. Streptococcus thermophilus but not Lact. bulgaricus grew in the rat diet when tested in vitro. Two enzyme systems (β‐galactosidase and lactase) were studied using, respectively, o‐nitrophenyl‐β‐D‐galactopyranoside (ONPG) and lactose as the test substrates. Enzyme levels estimated with both substrates. increased in the gut contents when rats were fed yoghurt but an increase was only found with ONPG in the intestinal mucosa fraction. The bacterial origin of all this increased activity is discussed. The other lactose‐containing diets did not affect enzyme activity to the same degree. Feeding yoghurt changed the lactobacillus flora from one which was predominantly hetero‐fermentative (Lact. reuteri) to one which was predominantly homofermentative (Lact. salivarius).
Microbial growth at reduced water activities: some physicochemical properties of compatible solutes
Authors: Chirife J. , Favetto G. , Fontán C. Ferro 
Published: March 2008

Chirife, J., Favetto, G. & Ferro Fontán, c. 1984. Microbial growth at reduced water activities: some physicochemical properties of compatible solutes. Journal of Applied Bacteriology56, 259–268.The water activities (aw) of solutions of D‐arabitol (a major compatible solute in yeasts grown at reduced aw) and also of related polyols (L‐arabitol, xylitol and ribitol) were determined at 25d̀C. The aw of saturated solutions of L‐proline and monopotassium L‐glutamate (solutes which accumulate in bacterial cells at reduced aw) were also determined. The viscosities of L‐proline, monopotassium L‐glutamate and D‐arabitol solutions were measured at 25, 30, 35 and 40d̀C for various concentrations up to high molalities. The relative viscosity curves were described using a theoretical model for the concentration dependence of viscosity. No relationship of viscosity of the electrolytes to effectiveness as ‘compatible solutes’ were evident, neither were the compatible solutes particularly effective ‘structure makers’ or ‘structure breakers.’
The uptake and utilization of Entodinium caudatum, bacteria, free amino acids and glucose by the rumen ciliate Entodinium bursa
Authors: Coleman G.S. , Hall F.J. 
Published: March 2008

Coleman, G.S. & Hall, F.J. 1984. The uptake and utilization of Entodinium caudatum, bacteria, free amino acids and glucose by the rumen ciliate Entodinium bursa. Journal of Applied Bacteriology56, 283–294.Washed suspensions of Entodinium bursa were incubated anaerobically with Entodinium caudatum, ten species of bacteria and a yeast. The rate of uptake and digestion of these micro‐organisms was investigated. Protozoa grown in vivo did not engulf Proteus mirabilis or Klebsiella aerogenes but rapidly took up Bacillus mega‐terium, Selenomonas ruminantium, Torulopsis glabrata and Streptococcus bouis, although only the last was digested with release of soluble material into the medium. Protozoa grown in vitro engulfed each of the bacteria tested, taking up Megasphaera elsdenii and i>Proteus mirabilis most rapidly. Individual bacterial species and mixed rumen bacteria were engulfed more rapidly (up to 20 times) by protozoa grown in vivo than those grown in vitro, although the latter digested over 80% of theB. megaterium, Escherichia coli and P. mirabilis taken up. Labelled Ent. caudatum was extensively digested after engulfment by Ent. bursa. Some of the digestion products were released into the medium but individual amino acids were transferred as such from Ent. caudatum protein to Ent. bursa protein. Engulfed bacteria and polysaccharide granules were transferred intact from one protozoon to the other. Free amino acids were also taken up intact from the medium into protozoal protein but there was little biosynthesis of amino acids from glucose. When available for engulfment Ent. caudatum was quantitatively a much more valuable source of amino acids for protein synthesis by Ent. bursa than free amino acids or bacteria.
Applications of fluorescent antibody for detecting capsular substances in Staphylococcus epidermidis
Authors: Ichiman Y. 
Published: March 2008

Ichiman, Y. 1984. Applications of fluorescent antibody for detecting capsular substances in Staphylococcus epidermidis, Journal of Applied Bacteriology56, 311–316.A fluorescent antibody technique was developed for the determination of the type of capsule of strains of Staphylococcus epidermidis. Many mouse virulent and avirulent strain populations were investigated. Of 300 fresh isolates of Staph. epidermidis, 27 were mouse virulent strains and of these 74.1% and 25.9% were mono‐ and polyvalent, respectively. The frequency of capsular type antigens I, II and III, produced by the 27 virulent strains was found to be 18.5%, 88.9% and 18.5%, the majority being capsular type II. In the mouse avirulent strains, capsular type antigen production was demonstrated in 263 out of 273 strains examined and mono‐ and polyvalent capsular types comprised 52.3% and 44.0%, respectively. Capsular type I, II, III strains and non‐typable strains occurred at frequencies of 15.0%, 95.2%, 34.9% and 3.7% respectively, the majority of mouse avirulent strains also being capsular type II. These results indicate that a majority of ordinary Staph. epidermidis produce capsular type antigens although the capability is quantitatively different according to strain.
A comparison of contact plate and calcium alginaie swab techniques for quantitative assessment of bacteriological contamination of environmental surfaces
Authors: Scott Elizabeth , Bloomfield Sally F. , Barlow C.G. 
Published: March 2008

Scott, E. Bloomfield, S.F. & Barlow, C.G. 1984. A comparison of contact plate and calcium alginate swab techniques for quantitative assessment of bacteriological contamination of environmental surfaces. Journal of Applied Bacteriology56, 317–320.A contact plate method for enumeration of bacteriological contamination at 9 environmental sites in 64 homes was compared with swab sampling techniques. Contamination levels of 100 or more organisms/21–25 cm2 were demonstrated more frequently using swab methods, but for some sites where low numbers of organisms were present, higher recovery rates were obtained using contact plates. When contamination levels from contact plate and swab techniques were compared according to rank order a good correlation was obtained. Results of this investigation indicate that the contact plate method is satisfactory for differentiation of ‘hygiene levels’ at environmental sites whilst facilitating handling of large numbers of samples in a field survey.
A new selective and differential agar medium for Escherichia coli and coliform organisms
Authors: Wright R.C. 
Published: March 2008

Wright, R.C. 1984. A new selective and differential agar medium for Escherichia coli and coliform organisms. Journal of Applied Bacteriology56, 381–388.An enriched lauryl sulphate‐aniline blue agar medium which is selective for Escherichia coli and coliform organisms is described. From faecal samples, the medium gave higher counts of colonies producing acid from lactose than media containing bile salts. From contaminated water and food samples, the medium gave comparable or higher counts of colonies identified as E. coli than standard media. Colonies of E. coli were more readily differentiated from those of other coliform organisms.
Infectivity of Rhizobium meliloti as affected by extracellular polysaccharides
Authors: Olivares J. , Bedmar E.J. , Martinez‐Molina E. 
Published: March 2008

Olivares, J., Bedmar, E.J. & Martinez‐Molina, E. 1984. Infectivity of Rhizobium meliloti as affected by extracellular polysaccharides. Journal of Applied Bacteriology56, 389–393.The addition of crude extracellular polysaccharide (EPS) preparations from highly infective Rhizobium meliloti increased the infectivity of a poorly infective strain. The addition of crude EPS preparations from another species did not promote nodu‐lation, suggesting the specificity of such an effect. Acid treatment of the crude EPS preparations resulted in total inhibition of nodulation.
A note on an improved molybdate agar for the selective isolation of yeasts from tropical fruits
Authors: Rale V.B. , Vakil J.R. 
Published: March 2008

Rale, V.B. & Vakil, J.R. 1984. A note on an improved molybdate agar for the selective isolation of yeasts from tropical fruits. Journal of Applied Bacteriology56, 409–413.Molybdate agar was fortified with 0.125% calcium propionate and used for routine isolation and differentiation of a variety of yeasts from mixed floras including large numbers of fungi and actinomycetes inhabiting tropical fruits. The results suggest that this technique could be usefully incorporated in yeast isolation and identification procedures.
Interactions between Azotobacter chroococcum and vesicular‐arbuscular mycorrhiza and their effects on plant growth
Authors: Brown Margaret E. , Carr G. R. 
Published: March 2008

Brown, M. E. & Garr, G. R. 1984 Interactions between Azotobacter chroo‐coccum and vesicular‐arbuscular mycorrhiza and their effects on plant growth. Journal of Applied Bacteriology56, 429–437.The effects of simultaneous inoculation of roots of lettuce seedlings with vesicular‐arbuscular endophytes and Azotobacter chroococcum are described. Endophytes alone increased yields of lettuce grown in partially sterilized P‐deficient soil, but not in the same unsterile soil. Dual inoculation with endophytes and Azotobacter in both soils produced larger plants than either inoculum alone. In another poorly structured unsterile soil with adequate P for plant growth, endophytes depressed yields of lettuce. There was no association between endophytes and Azotobacter. In none of the experiments did Azotobacter influence the level of endophyte infection in the roots; but numbers of Azotobacter on the root systems were decreased in the presence of the endophytes. Azotobacter alone always increased growth of young plants before the effects of the endophytes were observed.
Radioactive labels for Protein A: evaluation in the indirect immunoradiometric assay (IRMA) for Bacillus anthracis spores
Authors: Phillips A. P. , Martin K.L. 
Published: March 2008

Phillips, A.P. & Martin, K.L. 1984. Radioactive labels for Protein A: evaluation in the indirect immunoradiometric assay (IRMA) for Bacillus anthracis spores. Journal of Applied Bacteriology56, 449–456.Staphylococcus aureus Protein A (SpA) labelled with [125I] by the Bolton & Hunter (1973) method performed about as well as labelled sheep anti‐rabbit globulin (SAR) in an indirect immunoradiometric assay (IRMA) for Bacillus anthracis spores immobilized on multispot microscope slides. SpA labelled with [3H] by propi‐onylation also performed well but would be expensive to use. SpA labelled with [3H] fluorodinitrobenzene, or labelled with [125I] by the chloramine T reaction gave erratic assay results, high noise values and low signal‐to‐noise ratios, indicating substantial direct binding of labelled SpA to the slide surface and to the bacterial preparation. The uptake of radioactively labelled SpA in the IRMA was compared with the fluorescence intensity of individual spores in a micro‐fluorometric immunofluorescence (IF) test involving dual labelled fluorescein‐[125I]‐SpA. The maximum number of SAR molecules bound to the mixture of spores and cell‐free antigens in the B. anthracis IRMA was about twice the maximum number of radioactively labelled SpA molecules bound. The SAR : SpA saturation binding ratio on the surface of the spores, however, was approximately the inverse of this. It is concluded that radioactively‐labelled SpA is not recommended in preference to anti‐species antibody reagents in bacterial IRMA tests but fiuorescein‐conjugated SpA deserves further consideration for use in microscope‐based IF tests for bacterial antigens.
A new rapid and sensitive bioluminescence assay for antibiotics that inhibit protein synthesis
Authors: Naveh A. , Potasman I. , Bassan H. , Ulitzur S. 
Published: March 2008

Naveh, A., Potasman, I., Bassan, H. & Ulitzur, S. 1984. A new rapid and sensitive bioluminescence assay for antibiotics that inhibit protein synthesis.Journal of Applied Bacteriology56, 457–463.A new sensitive, rapid and simple bioluminescence assay for antibiotics inhibiting protein synthesis is described. In this assay the ability of the tested antibiotic to inhibit the de novo synthesis of the enzymes participating in the bacterial luminescence system is determined by means of a dark variant of a luminous bacterium that undergoes prompt induction of the luminescence system with certain DNA‐intercalating agents. Upon induction, the in vivo luminescence of the dark variant is increased more than 50‐fold within 30 min. Antibiotics that block the de novo synthesis of protein limit the development of luminescence at a level that was found to be a function of the antibiotic concentration. The minimum detectable concentration of antibiotics in the bioluminescence test, after 45–60 min of incubation, was 0.1 μg ml for streptomycin, gentamicin, kanamycin, lincomycin and chlorampheni‐col and 0.3 μg/ml for neomycin, clindamycin and spectinomycin. The new bioluminescence test has been used to assay these antibiotics in serum.