Study of the influence of sporulation conditions on heat resistance of Geobacillus stearothermophilus used in the development of biological indicators for steam sterilization.

Biological indicators are important tools in infection control via sterilization process monitoring. The use of a standardized spore crop with a well-defined heat resistance will guarantee the quality of a biological indicator. Ambient factors during sporulation can affect spore characteristics and properties, including heat resistance.

Relations between phenotypic changes of spores and biofilm production by Bacillus atrophaeus ATCC 9372 growing in solid-state fermentation.

Bacillus spp. spores are usually obtained from strains cultivated in artificial media. However, in natural habitats, spores are predominantly formed from bacteria present in highly surface-associated communities of cells.

Development of a low-cost sterilization biological indicator using Bacillus atrophaeus by solid-state fermentation.

The production of biological indicators involving bacterial sporulation and multi-step downstream processes has been described. The goal of the present work was to use fermented material as the final product in a biological indicator, thereby reducing processing steps and costs. The performance of three different inexpensive supports (vermiculite, sand, and sugarcane bagasse) was assessed by determining Bacillus atrophaeus sporulation during solid-state fermentation and by assessing the direct use of the fermentation products in the subsequent steps of the process.

Bioindicator production with Bacillus atrophaeus' thermal-resistant spores cultivated by solid-state fermentation.

Bacillus atrophaeus' spores are used in the preparation of bioindicators to monitor the dry heat, ethylene oxide, and plasma sterilization processes and in tests to assess sterilizing products. Earlier production methods involved culture in chemically defined medium to support sporulation with the disadvantage of requiring an extended period of time (14 days) besides high cost of substrates. The effect of cultivation conditions by solid-state fermentation (SSF) was investigated aiming at improving the cost-productivity relation.

Selection and optimization of Bacillus atrophaeus inoculum medium and its effect on spore yield and thermal resistance.

Bacillus atrophaeus's spores are used as biological indicators to monitor sterilization processes and as a Bacillus anthracis surrogate in the development and validation of biosafety methods. The regular use of biological indicators to evaluate the efficiency of sterilization processes is a legal requirement for health services. However, its high cost hinders its widespread use.