RT Journal Article SR Electronic T1 The Effect of Media Composition on the Thermal Resistance of Bacillus stearothermophilus JF PDA Journal of Pharmaceutical Science and Technology JO PDA J Pharm Sci Technol FD Parenteral Drug Association (PDA) SP 398 OP 412 VO 54 IS 5 A1 Penna, Thereza Christina Vessoni A1 Machoshvili, Irene A. A1 Taqueda, Maria Elena Santos A1 Ishii, Marina YR 2000 UL http://journal.pda.org/content/54/5/398.abstract AB Spores of Bacillus stearothermophilus ATCC 7953 were developed at 62° 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 demonstrated a strong interaction of yeast/peptone/ammonium phosphate, contributing positively to the best sporulation yield (6–7 log10 spores). The most influential medium components on the thermal resistance (at 121° C) of spores in suspension (calcium acetate, pH 9.7) were yeast extract (positively) and potassium phosphate (negatively), both creating the positive interaction, for spores from a 6-day incubation period. However, the strong negative effect of sodium chloride decreased the D-value from 1.81 min to 0.57 min upon increasing the incubation period (62° C) from 3 days to 6 days. The D-glucose and peptone exhibited greater effects than the yeast extract and potassium phosphate interaction on Dvalues for 3-day spores on strip, just as the highly joint-positive peptone/sodium chloride effect maintained the thermal resistance of 6-day spores on strips. The spores on strip system showed less stability than the spores in suspension. The most stable spore system confirmed D-values at 121° C at a range between 1.5 min and 1.9 min, which were obtained by keeping sodium chloride and potassium phosphate at minimum concentrations and yeast extract and peptone at maximum concentrations, regardless of the 3- to 6-day sporulation.