Paik W W, Sherry E J, Stern J A
Appl Microbiol. 1969 Nov;18(5):901-5. doi: 10.1128/am.18.5.901-905.1969.
Dry-heat sterilization of planetary lander capsules requires a knowledge of the thermal resistivity of microorganisms in the environment to which they will be subjected during sterilization of the space hardware. The dry-heat resistance of Bacillus subtilis var. niger spores on various lander capsule materials was determined at 125 C. Eight surface materials were evaluated, including a reference material, stainless steel. Survivor curves were computed, and decimal reduction times (D values) were obtained by a linear regression analysis. In four tests on stainless steel, the average value of D at 125 C was 17.07 min. The D values for the other seven materials tested ranged from 18.64 min on magnesium surfaces to 20.83 min on conversion-coated magnesium. Of the materials evaluated, the results indicate that there is only a significant difference in the thermal resistance of B. subtilis var. niger spores on conversion-coated magnesium and conversion-coated aluminum from that on the reference material, stainless steel. The differences in D values for all the test surfaces may be the result of variations in test procedures rather than the effect of the surfaces on the thermal resistivity of the spores.
对行星着陆器太空舱进行干热灭菌，需要了解太空硬件灭菌过程中微生物所处环境的热阻率。在125℃下测定了枯草芽孢杆菌黑色变种芽孢在各种着陆器太空舱材料上的耐热性。评估了八种表面材料，包括一种参考材料不锈钢。计算了存活曲线，并通过线性回归分析获得了十进制减少时间（D值）。在对不锈钢进行的四项测试中，125℃下D的平均值为17.07分钟。测试的其他七种材料的D值范围从镁表面的18.64分钟到转化涂层镁表面的20.83分钟。在所评估的材料中，结果表明，枯草芽孢杆菌黑色变种芽孢在转化涂层镁和转化涂层铝上的耐热性与参考材料不锈钢相比，仅存在显著差异。所有测试表面D值的差异可能是测试程序变化的结果，而非表面对芽孢热阻率的影响。
