Coliform Organisms In Water Research Articles

Radiometric Method for the Detection of Coliform Organisms in Water

A new radiometric method for the detection of coliform bacteria in water has been described. The method is based on the release of 14 CO 2 from [ 14 C]lactose by bacteria suspended in growth medium and incubated at 37 C. The evolved 14 CO 2 is trapped by hyamine hydroxide and counted in a liquid scintillation spectrometer. The method permits the detection of 1 to 10 organisms within 6 h of incubation. Coliform bacteria suspended in water for several days recover from starvation and may be quantitated by the proposed method. Bacteria from water samples may also be concentrated by filtration through membrane filters and detected by the radiometric assay.

Radiometric Method for the Detection of Coliform Organisms in Water

A new radiometric method for the detection of coliform bacteria in water has been described. The method is based on the release of (14)CO(2) from [(14)C]lactose by bacteria suspended in growth medium and incubated at 37 C. The evolved (14)CO(2) is trapped by hyamine hydroxide and counted in a liquid scintillation spectrometer. The method permits the detection of 1 to 10 organisms within 6 h of incubation. Coliform bacteria suspended in water for several days recover from starvation and may be quantitated by the proposed method. Bacteria from water samples may also be concentrated by filtration through membrane filters and detected by the radiometric assay.

Comparison of membrane filtration and multiple tube methods for the enumeration of coliform organisms in water

SUMMARYThe membrane methods described in Report 71 on the bacteriological examination of water supplies (Report, 1969) for the enumeration of coliform organisms and Escherichia coli in waters, together with a glutamate membrane method, were compared with the glutamate multiple tube method recommended in Report 71 and an incubation procedure similar to that used for membranes with the first 4 hr. at 30°C., and with MacConkey broth in multiple tubes. Although there were some differences between individual laboratories, the combined results from all participating laboratories showed that standard and extended membrane methods gave significantly higher results than the glutamate tube method for coliform organisms in both chlorinated and unchlorinated waters, but significantly lower results for Esch. coli with chlorinated waters and equivocal results with unchlorinated waters. Extended membranes gave higher results than glutamate tubes in larger proportions of samples than did standard membranes. Although transport membranes did not do so well as standard membrane methods, the results were usually in agreement with glutamate tubes except for Esch. coli in chlorinated waters. The glutamate membranes were unsatisfactory. Preliminary incubation of glutamate at 30° C. made little difference to the results.

A minerals-modified glutamate medium for the enumeration of coliform organisms in water

SUMMARYOxoid dehydrated MacConkey broth was compared with laboratory-prepared Gray's improved formate lactose glutamate medium and with two dehydrated versions of it, by participants in ten laboratories. A variety of chlorinated and unchlorinated water samples was used. The superiority of the glutamate media over MacConkey broth for the detection of coliform organisms in water was again confirmed. The minerals-modified version, either dehydrated or laboratory-prepared, gave the best results and is the medium recommended for use in water examination. Care should be taken to ensure that the final pH after sterilization is 6·7.

Detection of Coliform Organisms by the Fluorescent‐Antibody Method

This article discusses experimentation with the use of the fluorescent‐antibody (FA) technique as a test for the presence of coliform organisms in water. The method involves the use of a fluorescence microscope on unknown cultures (antigens) treated with solutions of fluorescein‐labeled antisera. The basic principle of the FA technique is presented and discussed in the article.

AN IMPROVED FORMATE LACTOSE GLUTAMATE MEDIUM FOR THE DETECTION OF ESCHERICHIA COLI AND OTHER COLIFORM ORGANISMS IN WATER.

A chemically defined fluid medium—improved formate lactose glutamate—is described of which the cost is less than a quarter that of standard MacConkey broth and which is at least equally suitable for routine bacteriological examination of water. It has actual advantages in that the medium after fermentation is clearer and that, therefore, acid and gas production is more easily seen; moreover more isolations of both coliform bacteria and ofEsch. coliare obtained with fewer false positive reactions. Trials with a solid version of the medium suggest that the relative freedom from false positive reactions arises from the failure of the medium to growCl. welchii—one of the commonest causes—and enterococci, another suspected participant. In fact, without any inhibitory agent the medium appears to be virtually specific for the coliform group and particularly favoursEsch. coli.It remains to be seen whether certain aerobic spore-bearers found from time to time in surface waters may, to some slight extent, interfere with the almost complete specificity so far discovered.The medium is recommended in place of MacConkey broth and other peptonecontaining media, not only for the prospect of better results, in that suppression of the coliform group does not occur, but also for cheapness and for freedom from the inevitable variability associated with media incorporating peptone and, particularly, bile salt. It is hoped that this medium will shortly become available commercially in dehydrated form at a price still considerably less than that required to make up MacConkey broth from its constituents.Some labour-saving curtailments in the routine of water examination are also suggested.It is hoped not only that the fluid medium will supplant MacConkey broth for the dilution method of water analysis but that the solid medium, without material alteration, will also prove suitable for water examination by membrane filtration.I am deeply grateful to my laboratory staff, particularly Mr J. H. Evans, F.I.M.L.T., and Mr G. H. Lowe, F.I.M.L.T., for undertaking so much of the work when routine work was particularly heavy, and for many valuable suggestions. My thanks in addition are due to Mrs Peggy Johnson and Mrs Marilyn Childs, who made up the medium, and also to the directors of the participating P.H.L.S. laboratories not only for having the work carried out but for helpful comments.

Evaluation of Membrane Filter Technique for Appraising Ohio River Water Quality

Under commission authorization and staff direction, members of the Orsanco Water Users Committee, during the period November 1956‐November 1957, carried out a comparative study of the membrane filter and standard dilution methods of enumerating coliform organisms in raw waters taken from the Ohio River and two tributary rivers. Following completion of the 13‐ month period of comparative tests, the same group conducted a study of three different confirmatory MF media, in order to ascertain whether any improvement was obtainable over the one‐step HD medium that had been used throughout the 13‐month period of comparative tests. The first trial was the two‐step HD medium against the one‐step HD medium that had been previously used. This test continued for 5 months, from January through May 1958. An overall summary of the results revealed that the two‐step HD medium yielded an average of 20 per cent higher coliform counts than the one‐step HD medium. Meanwhile, interest had been aroused in a one‐step medium proposed by Fifield and Schaufus. Although only a limited time was available to test this medium, comparative tests against the two‐step HD medium, during June and July 1958, showed an average of 16 per cent higher counts than the two‐step medium – an encouraging result. It thus was indicated that substantially higher counts, amounting to nearly 40 per cent, were obtainable with the one‐step MF medium as compared to the one‐step HD medium. The conclusions drawn from this study, made by six laboratories over a period of about 20 months, were that the use of the membrane filter is an acceptable alternative method of enumerating coliform organisms in water, as compared to the standard dilution method, and is preferable because of its precision, speed, economy of space, and its freedom from statistical complications.

A comparison of media for the detection of coliform organisms in water.

Five media—MacConkey broth, lactose broth, Teepol broth, lauryl sulphate broth and glucose glutamic acid medium—have been compared as primary media for the isolation of coliform organisms from 1691 samples of water received for examination during a period of 18 months.Of these samples 1043 (61·7%) gave an identical result in all five media. In the other 648 (38·3%) samples there were differences either in the types of coliform organism isolated or in the rapidity with which the reactions appeared in the different media. The differences in the final yields of coliform organisms andEscherichia coliin the five media are not statistically significant.There were differences in the number of false presumptive positive reactions given by the different media—lactose broth giving many more false presumptive positive reactions than any of the other media and nearly six times as many as MacConkey broth, which gave the smallest number.All the reactions tended to appear rather more slowly in glucose glutamic acid medium than in the other media.Glucose glutamic acid medium has the advantages of being a chemically defined medium and of not containing any substances which are likely to be inhibitory to coliform organisms. Other glutamic acid media may be found on further investigation to give better results than the present glucose glutamic acid medium, but those presented here suggest that media containing glutamic acid are worthy of further investigation.I am indebted to Dr Ian Sutherland of the M.R.C. Statistical Research Unit for statistical advice and to Dr R. D. Gray of the Public Health Laboratory, Newport (Mon.) and to Dr A. H. Tomlinson of the Public Health Laboratory, Oxford, for much helpful criticism.

A COMPARISON between MacConkey broth and glutamic acid media for the detection of coliform organisms in water.

Folpmers's glutamic acid medium and the lactose modification described by Burman & Oliver (1952) have been compared with MacConkey broth in the pre-sumptive coliform test of 4421 samples of water examined at six different laboratories in England and Wales. As compared with MacConkey broth, both glutamic acid media gave between 8 and 10% more isolations of Bact. coli I; the glucose medium additionally gave an increase of 6% in other coliform organisms, but this was associated with a very heavy excess (232%) of false positive results; lactose glutamic acid satisfactorily controlled false positive reactions, giving a reduction of 36%, but also suppressed by 35% the isolations of coliform organisms other than Bact. coli I.MacConkey broth gave the largest early (18 hr.) yield of positive results, but the results at the end of 24 hr. were approximately the same with all three media. Preliminary warming of the inoculated tube had only a trivial effect on the rapidity with which the organisms grew, but the warming resulted in a slightly higher total yield of Bact. coli I in the glutamic acid media. Incubation at 42° C. for 18 hr. followed by 37° C. for 30 hr. was found to be inferior to incubation at 37° C. for 48 hr. in the case of lightly polluted waters, in that true coliform organisms were suppressed without any compensating advantage in the yield of Bact. coli I.

Effects of Media, Temperature, and Humidity on the Development of Coliform Organisms on Molecular Filter Membranes

membrane filter procedure for the bacteriological examination of water, although not formally introduced into the United States until 1947, has been used in Europe for many years. Germany and Russia utilized the membrane filter procedure for the bacteriological control of their water supplies during World War II, when other laboratory facilities were not available. Since 1947, many papers have been written on the applicability and feasibility of using the molecular filter (MF) membrane in sanitary water analysis. From 1947 through 1954, much research was devoted to finding an acceptable membrane filter procedure for detecting and enumerating coliform organisms in water. The committee which prepared the tenth edition of Standard Methods (1) recognized the potentialities of the MF membrane procedure and listed it as a tentative standard. Since 1954, several articles have been published which recommend acceptance of the test for the bacteriological control of potable waters. The procedure recommended in Standard Methods employs a two-step liquid nutrient application and careful control of temperature and humidity during incubation. The two-step appl cation requires considerable time for preparation of media and materials and is cumbersome to use because of the

New Medium for Bacteriological Analysis With Molecular Filter Membranes

Journal AWWAVolume 45, Issue 9 p. 945-951 Article New Medium for Bacteriological Analysis With Molecular Filter Membranes George S. Yee, George S. YeeSearch for more papers by this authorWilfred B. Krabek, Wilfred B. KrabekSearch for more papers by this authorCharles P. Schaufus, Charles P. SchaufusSearch for more papers by this author George S. Yee, George S. YeeSearch for more papers by this authorWilfred B. Krabek, Wilfred B. KrabekSearch for more papers by this authorCharles P. Schaufus, Charles P. SchaufusSearch for more papers by this author First published: 01 September 1953 https://doi.org/10.1002/j.1551-8833.1953.tb16518.xCitations: 4AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume45, Issue9September 1953Pages 945-951 RelatedInformation

A Practical Study of Lauryl Sulfate Tryptose Broth for Detection of the Presence of Coliform Organisms in Water

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A Comparison of MacConkey's Broth and Standard Lactose Broth as Media for Detection of Coliform Organisms in Water

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A comparison of two methods of assessing the number of different types of coliform organisms in water

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