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Filtering by: Has journal Journal of Substance Abuse Treatment Remove constraint Has journal: Journal of Substance Abuse Treatment Advisor Sandine, William E. Remove constraint Advisor: Sandine, William E. Degree Level Master's Remove constraint Degree Level: Master's

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  • Microbiological control of food spoilage and pathogenic microorganisms in refrigerated foods

    Creator:
    Al-Zoreky, Nageb
    Abstract:
    Microgard, a commercially-available pasteurized fermented milk, was found inhibitory to gram negative bacteria such as Pseudomonas putida, some well-known foodborne pathogens (e.g. Salmonella, Yersinia and Aeromonas) and some fungi as revealed by an agar incorporation assay method. Gram positive bacteria, however, were not inhibited. Rather, some bacteria in this group...
    Resource Type:
    Masters Thesis
    Full Text:
    emulsifying substances antagonized Microgard whereas treatment with proteases at an initial pH of 11.0

  • Lactic streptococci: growth characteristics and plasmid profiles of drug- and bacteriophage-insensitive mutants

    Creator:
    Wulf, John J.
    Abstract:
    Fast acid-producing streptomycin-resistant mutants for several strains of lactic streptococci currently used in commercial Cheddar cheese manufacture were isolated. Their isolation involved use of a recently developed differential plating medium that allows identification of fast acid-producing colonies. Both parents and mutants were characterized with regard to growth, acid production, proteolytic...
    Resource Type:
    Masters Thesis
    Full Text:
    storage abuse influenced the incidence of slow acid- producing variants in three selected strains of

  • Isolation of auxotrophic mutants of Bacillus cereus

    Creator:
    Keng, Jiun Guang
    Abstract:
    Bacillus cereus excretes large amounts of penicillinase into growth media during incubation, hence the widely-used penicillin selection technique for isolating biochemical mutants of bacteria is not applicable to this species. Genetic transfer in B. cereus has not been reported; this is partly due to the lack of an effective isolation...
    Resource Type:
    Masters Thesis
    Full Text:
    treatment of Epoffi, 37 9 Frequencies of auxotrophs obtained by DES induction of spores of B. cereu.s 6464D

  • Metabolism of aroma bacteria as related to diacetyl production

    Creator:
    Brown, Ruth Elaine
    Abstract:
    Factors influencing diacetyl production by the aroma bacteria Leuconostoc citrovorum and Streptococcus diacetilactis were investigated. When grown in association with lactic streptococci, L. citrovorum strain 91404 decreased in cell numbers from 10⁸ to 10⁶ over two weeks of daily subculturing in sterile non-fat milk incubated at 21°C. The ability to...
    Resource Type:
    Masters Thesis
    Full Text:
    affected. Treatment of the milk with 0.03% H2O2 and sufficient 0.004% catalase to decompose the H2O2

  • Mechanisms of lactose metabolism by strains of Streptococcus lactis

    Creator:
    Walter, Leslie Alva
    Abstract:
    Rapid acid production by lactic streptococci used in the manufacture of fermented dairy products is essential to the economy of the industry and to the public health of consumers. There remains to developed, however, an adequate laboratory procedure to detect and distinguish between slow and fast strains of these bacteria....
    Resource Type:
    Masters Thesis
    Full Text:
    nitrogen. Lysozyme Treatment The treatment of cells with lysozyme was an attempt to gently expose the

  • Characterization of 16S Ribosomal RNA Probe-Isolated Lactococci from nature for use in Cheddar cheese manufacture

    Creator:
    Daniels, Brent E.
    Abstract:
    Strains of Lactococcus lactis ssp. lactis and Lactococcus lactis ssp. cremoris with potential use in the food industry which had been previously isolated from nature using 16S rRNA probes were characterized for unique identifying traits and for attributes important for potential use in cheese manufacture. Strains of Lc. cremoris which...
    Resource Type:
    Masters Thesis
    Full Text:
    following treatment with UV light, and untreated controls of each, incubation at 30° C for 5 hours. 17

  • Effect of quaternary ammonium compounds on bacteria : comparison of sensitive and resistant strains of the same species

    Creator:
    Albin, Inga Anna Schroder
    Abstract:
    To determine whether some bacteria are more susceptible than others to quaternary ammonium compounds, the following bacteria were grown on agar slants containing various concentrations of alkyl dimethyl ethyl benzyl ammonium chloride (ADEBAC), and alkyl dimethyl benzyl ammonium chloride (ADBAC): Aerobacter aerogenes 12658, Alcaligenes metalcaligenes, Brevibacterium linens, Chromobacterium lividum, Escherichia...
    Resource Type:
    Masters Thesis
    Full Text:
    (1947) demonstrated, by means of an electron microscope, that treatment of bacterial cells with

  • A comparative study of Lactobacillus acidophilus strains

    Creator:
    Fowlkes, Charles Edward
    Resource Type:
    Masters Thesis
    Full Text:
    A Comparative Study of Lactobacillus acidophilus Strains

  • Factors related to resisitance of bacteria to quaternary ammonium germicides

    Creator:
    Wang, Wei-sheng
    Abstract:
    This study was carried out to compare the effects of a quaternary ammonium compound (QAC) upon strains of Pseudomonas aeruginosa which were either sensitive or resistant to the germicide. The cationic QAC used was alkyldimethylbenzylammonium chloride. The resistant types were isolated from the sensitive population by selection of mutants which...
    Resource Type:
    Masters Thesis
    Full Text:
    substance was intimately associated with the surface of the normal cells but at a much greater

  • Growth of lactococci relative to antibiotic and quaternary ammonium compounds

    Creator:
    Valladao, Marilin
    Abstract:
    The work presented in this thesis is concerned with the effect of several antibiotics and quaternary ammonium sanitizers upon growth of lactic acid bacteria. Section I reports the purification of beta-lactamase from Lactococcus cremoris PR-108, by ion exchange chromatography, using the chromogenic substrate pyridine-2-azo-p-dimethylaniline (PADAC) as the enzymatic indicator. Section...
    Resource Type:
    Masters Thesis
    Full Text:
    Growth of lactococci relative to antibiotic and quaternary