摘要:

ABSTRACTEight strains of Bacillus spp. were examined for production of toxin(s). Three strains of Bacillus cereus produced toxins lethal to mice. The culture filtrate of Bacillus cereus BIS‐59 contained two lethal toxins. One was a hemolysin and the other a nonhemolytic glycoprotein. The growth of cells in fresh beef infusion broth resulted in high toxin production, compared to growth in tryptone‐glucose‐yeast extract or nutrient broth. Separate identities for the two toxins from B. vcereus BIS‐59 were established on the basis of hemolytic activity, separation profiles on Sephadex gel filtration, responses to heat and radiation and kinetics of their production during the growth of the o

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1986.tb00553.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTThe effectiveness of a radicidation process using 1 kGy of gamma radiation was evaluated with respect to the destruction of Vibrio parahaemolyticus contamination in shrimp. D10values of this pathogen ranged from 0.03 kGy in frozen buffer to 0.10 kGy in naturally contaminated frozen shrimp. The efficacy of the process was demonstrated.

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1986.tb00554.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTLipopolysaccharide‐protein (LPS‐P) vaccine prepared from cells of S. typhimurium contains 11% protein. Immunization of mice with LPS‐P intraperitoneally at a dose level of 50 μg/mouse conferred 100% protection against subsequent challenge with S. typhimurium and seven other strains of Salmonella each possessing typical O‐antigen determinants. The immunity lasts for six months and the vaccine is equally effective in all six strains of mice studied. The lyophilized LPS‐P preparation is stable for eighteen months, thus providing opportunity for large scale field trial e

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1986.tb00555.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTMycelial growth and toxin production by Asperigillus parasiticus were inhibited by garlic concentrations of 0.3–0.4%. When the fungus was grown in broth, aflatoxin B1production was inhibited at a garlic concentration of 0.3% while aflatoxin G1production was inhibited by 0.25% garlic. When growth on rice, aflatoxin B1was detected at garlic concentrations of up to 2.5%. Aflatoxin G1was detected at 1.25% garlic concentration but not above this leve

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1986.tb00556.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTUsing factorial design experiments and MPN methodology, we evaluated the probability (P) of growth initiation of 17 individual proteolytic (A,B,F) and non‐proteolytic (B,E,F) C. botulinum strains (spores and cells) in a model broth as it is affected by strain, cell and serologic type, inoculum size (100–106), temperature (4–47°C) and time of incubation (up to 28 days). Regression analyses of the P of growth of the most capable strains for all conditions tested, allowed the development of quantitative equations relating P of growth initiation by one spore or cell to the variables studied. The close agreement between observed and predicted Ps demonstrated the potential usefullness of the modeling approach in studying microbial interactions with food enviro

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1986.tb00557.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTEarlier work characterizing the effects of glucose analogs on growth and aflatoxin production by Aspergillus parasiticus was expanded by assessing the effects of β‐methylglucose (βMG), 3‐0‐methylglucose (3MG) and thioglucose (TG). As sole carbon source of conidia‐initiated cultures, βMG and 3MG, but not TG, supported growth, but none supported toxin production. In glucose‐containing replacement cultures, MG appeared to stimulate toxin production, while TG was inhibitory and 3MG had no effect. Preliminary assessment of the effects of βMG, 3MG, TG, 2‐deoxyglucose and α‐methylglucose on glucose uptake and utilization by glucose‐containing replacement cultures indicated that under conditions that favor aflatoxin production, none of the analogs inhibited the uptake of14C‐labelled glucose. It appears that the glucose transport system(s) of A. parasiticus may be unusual in that it is insensitive to a vari

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1986.tb00558.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTGlucose, 2‐deoxyglucose (2‐DOG), and α‐methylglucose (α‐MG) inhibited staphylococcal enteroxin A (SEA) synthesis by Staphylococcus aureus 196E whereas β‐methylglucose (β‐MG) and 3‐0‐methylglucose (3‐0‐MG) did not inhibit even at high concentrations. Glucose and β‐MG decreased the pH (<6.0) whereas the pH with 2‐DOG, α‐MG was above 8.0 at 24 h. Glucose (at levels not inhibitory to SEA synthesis) potentiated the inhibition of toxin synthesis by 2‐DOG and β‐MG and the glucose‐analog combinations had a decreased pH. The inhibition of SEA synthesis by glucose, glucose analogs, or glucose‐analog combinations does not appear to be directly related to a decline in pH. The inhibitory effects shown by glucose and its analog suggest that SEA synthesis may be regulated by a me

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1986.tb00559.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY