Use of soybean vinasses as a germinant medium for a Geobacillus stearothermophilus ATCC 7953 sterilization biological indicator

• Published in: Applied microbiology and biotechnology 2011-04, Vol.90 (2), p.713-719
• Main Authors: Dlugokenski, Regina E. F, Sella, Sandra R. B. R, Guizelini, Belquis P, Vandenberghe, Luciana P. S, Woiciechowski, Adenise L, Soccol, Carlos R, Minozzo, João C
• Format: Article
• Language: English
• Subjects: Agricultural industry; Aluminum; Bioindicators; Biological and medical sciences; Biomedical and Life Sciences; Biotechnology; By products; Calcium chloride; Culture Media - chemistry; Culture Media - metabolism; Environmental impact; Ethanol; Ethanol - metabolism; Ethanol by-products; Fundamental and applied biological sciences. Psychology; G. stearothermophilus; Geobacillus; Geobacillus stearothermophilus - growth & development; Geobacillus stearothermophilus - metabolism; Germination medium; Glycine max - chemistry; Glycine max - metabolism; Heat resistance; Hot Temperature; Indicator organisms; indicator species; Industrial Waste; Industrial wastes; Life Sciences; Methods and Protocols; Microbial Genetics and Genomics; Microbial Viability; Microbiology; Molasses; Production costs; Soybean vinasse; Soybeans; Spores, Bacterial - growth & development; Sterilization; Studies; Sugarcane; Syrups & sweeteners; Yeasts
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s00253-011-3160-3

A novel low-cost medium was developed from by-products and wastes from the ethanol agro-industry to replace commercial media in the production of a steam sterilization biological indicator (BI). Various recovery media were developed using soybean or sugarcane molasses and vinasse to prepare a self-contained BI. Media performance was evaluated by viability and heat resistance (D ₁₂₁ °C value) according to regulatory standards. A medium produced with a soybean vinasse ratio of 1:70 (1.4%) (w/v) produced the results, with D ₁₂₁ °C = 2.9 ± 0.5 min and Usk = 12.7 ± 2.1 min. The addition of 0.8% (w/v) yeast extract improved the germination of heat-damaged spores. The pH variation from 6.0 to 7.3 resulted in a gradual increase in the D ₁₂₁ °C value. The absence of calcium chloride resulted in a decrease in germination, while no significant differences were observed with starch addition. Soybean vinasses may thus be used as the main component of a culture medium to substitute for commercial media in the production of self-contained biological indicators. The use of ethanol production waste in this biotechnological process realized a reliable performance, minimized the environmental impact, and decreased BI production costs while producing a high quality product.