VANCOMYCIN SUSCEPTIBILITY AS AN AID TO THE IDENTIFICATION OF LACTOBACILLI

Forty strains of lactobacilli isolated from probiotic supplements or functional foods, and two clinical isolates, have been identified by API 50 CHL and tested for susceptibility to vancomycin. All the Lactobacillus acidophilus (16) and Lact. delbreuckii (two) strains were sensitive to vancomycin, while all the other strains (mainly Lact. rhamnosus, 15) were resistant. Susceptibility to other antibiotics was not species-specific. Differential susceptibility to vancomycin may be helpful in speciation of lactobacilli.     

THE SEPARATION OF NINE SPECIES OF THE IRIDACEAE BY PAPER CHROMATOGRAPHY

Riley , H. P., and T. R. Bryant . (U. Kentucky, Lexington.) The separation of nine species of the Iridaceae by paper chromatography. Amer. Jour. Bot. 48(2): 133–137, Illus. 1961.—Chromatograms were made from small pieces of the root tip of 9 species of 4 genera of the Iridaceae. Under ultraviolet light, the patterns of Watsonia ardernei and W. vanderspuyae were almost identical which suggests that they are closely related species. On the basis of chromatographic patterns, W. fourcadei apparently is not so closely related to them but is rather closely related to W. wilmaniae; W. pyramidata and W. wordsworthiana are less closely related to the other species. The patterns of Dietes grandiflora, Babiana bainesii and Sparaxis aureum are strikingly different from one another and from those of the species of Watsonia.     

THE DIFFERENTIATION OF BACTERIAL SPECIES BY PAPER CHROMATOGRAPHY. IV. AN EXAMINATION OF THE MICROCOCCI, WITH SPECIAL REFERENCE TO THE INFLUENCE ON THE CHROMATOGRAMS OF MEDIUM AND AGE OF CULTURE

SUMMARY: The amino acid and peptide content of the micrococci as revealed by paper chromatography depended on the physiological age of the culture and on the composition of the growth medium. The use of different peptones in a Yeastrel glucose peptone medium resulted in minor changes in the chromatograms. A greater effect was noted when glucose was omitted. When the composition of the growth medium was standardized the best comparison of cultures was afforded by the preparation of chromatograms from samples taken in the late logarithmic and early stationary phases of growth.     

THE DIFFERENTIATION OF SPECIES OF LACTOBACILLI AND STREPTOCOCCI BY MEANS OF PAPER PARTITION CHROMATOGRAPHY

SUMMARY: Washed cells of micro-organisms were extracted with 10% acetic acid and the extracts subjected to two-dimensional paper partition chromatography. With closely related strains within species already defined serologically and physiologically, the patterns of amino acids and peptides revealed by ninhydrin were relatively constant; but with different species variations were noted, even between species hitherto not easy to differentiate.     

THE DIFFERENTIATION OF BACTERIAL SPECIES BY PAPER CHROMATOGRAPHY. V. PRELIMINARY EXAMINATION OF THE MICROCOCCI

SUMMARY: Chromatograms of unhydrolyzed extracts of the type strains of the Cowan groups of the micrococci and of other representatives of these groups have shown that the resulting pattern of ninhydrin-positive spots is useful taxonomically.
The grouping based on the chromatograms agreed well with the Gibson grouping, but indicated that Cowans group III contained some dissimilar organisms.     

THE USE OF TROFIC AS AN AID FOR THE MANAGEMENT OF EUTROPHIC LAKES

SUMMARY

As a result of eutrophication studies that have been performed by the National Institute for Water Research for many years it was decided in 1980 that a detailed investigation into this area take place. Hypertrophic Hartbeespoort Dam was selected as the study site. A simulation model, named TROFIC, of the ecosystem was developed and updated over a three-year research program. Different management strategies were performed to attempt to reduce the size of phytoplankton standing stock and to modify the phytoplankton species composition so that blue-green algae are no longer dominant. In this paper the applicability of each strategy to the model is examined by means of results obtained and conclusions drawn from these results.