Thereza Christina Vessoni Penna

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To evaluate the effectiveness of 11 commonly used ingredients to improve Bacillus stearothermophilus ATCC 7953 sporulation, with high spore yields in a short period of incubation, 32 composition media were set up by a fractional factorial 2IV11-6 design at two levels: D-glucose (0.018-0.25%), L-glutamic acid (0.040-0.10%), yeast extract (0.050-0.40%),(More)
PURPOSE Endotoxins, also called lipopolysaccharides (LPS), are major contaminants found in commercially available proteins or biologically active substances, which often complicate study of the biological effects of the main ingredient. The presence of small amounts of endotoxin in recombinant protein preparations can cause side effects in host organism(More)
BACKGROUND Purified water for pharmaceutical purposes must be free of microbial contamination and pyrogens. Even with the additional sanitary and disinfecting treatments applied to the system (sequential operational stages), Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseudomonas alcaligenes, Pseudomonas picketti, Flavobacterium aureum, Acinetobacter(More)
The kinetic inactivation parameters of four wild strains and two enterotoxigenic strains ofEscherichia coli exposed to commercial calcium hypochlorite were determined. The four wild strains (1A, 3C, 4D and 8H) were isolated from lettuce bought in São Paulo (Brazil), and the two enterotoxigenic strains (TR69 and TR101) were originally isolated from human(More)
The production of nisin by batch culture of Lactococcus lactis ATCC 11454 in MRS broth (pH 6.5), as treated in 30 assays, that were set up by a fractional factorial design of two levels (2[4-1]), was improved. The minimum and maximum concentrations of sucrose (5.0-12.5 g/L), asparagine (7.5-75 g/L), potassium phosphate (6.0-18.0 g/L), and Tween-80 (1.0-6.6(More)
Spores of Bacillus stearothermophilus ATCC 7953 were developed at 62 degrees C on 32 media composed of various amounts of 11 components: D-glucose, L-glutamic acid, yeast extract, peptone, sodium chloride, magnesium sulfate, ammonium phosphate, potassium phosphate, calcium chloride, ferrous sulfate and manganese sulfate. Statistical models were used and(More)
The interference of eight components in the yield of sporulation and thermal resistance to moist heat (121 degrees C) of Bacillus stearothermophilus spores suspended in 0.02 M calcium acetate solution and inoculated on paper strips previously treated with calcium acetate/calcium hydroxide was studied. The spore yield of 1.0 x 10(8)mL was developed at 62(More)
BACKGROUND Prior to the selection of disinfectants for low, intermediate and high (sterilizing) levels, the decimal reduction time, D-value, for the most common and persistent bacteria identified at a health care facility should be determined. METHODS The D-value was determined by inoculating 100 mL of disinfecting solution with 1 mL of a bacterial(More)
In biotechnology, endotoxin (LPS) removal from recombinant proteins is a critical and challenging step in the preparation of injectable therapeutics, as endotoxin is a natural component of bacterial expression systems widely used to manufacture therapeutic proteins. The viability of large-scale industrial production of recombinant biomolecules of(More)
Paper strips inoculated with spores of Bacillus stearothermophilus ATCC 7953 were conventionally dried (lot 1) and lyophilized (lot 2); stored in defined environments of 32 and 86% relative humidity at 10, 25 and 33 degrees C for 210 d; and submitted to moist heat treatments at 121 degrees C. A significant decrease in thermal resistance from initial(More)