Comparison of Different Culture Methods for the Detection of Bacillus cereus Group in Cosmetics. (30th June 2020)

• Record Type: Journal Article
• Authors: Yossa, Nadine; Hoang, Son T; Canida, Travis; Bell, Rebecca; Tallent, Sandra; Brown, Eric; Hammack, Thomas
• Is Part Of: Journal of AOAC International. Volume 103:Number 4(2020)
• Page Start: 1129
• Page End: 1139
• Publication Date: 2020-06-30
• Subjects: Agricultural chemistry -- Periodicals; Food -- Analysis -- Periodicals; 543
• DOI: 10.1093/jaoacint/qsaa016
• Languages: English
• ISSNs: 1060-3271

Abstract

Abstract: Background: The U.S. Food and Drug Administration (FDA) Bacteriological Analytical Manual (BAM) reference culture method uses Modified Letheen Broth (MLB) for microbiological analyses for all types of cosmetic products. Objective: This study evaluated the effectiveness of MLB and Tryptone Azolectin Tween (TAT) broths using BAM reference culture method for cosmetics. Methods: Pure spore suspensions of B. cereus group members were experimentally spiked (McF: 0.5) into cosmetic products. After an aging period of 72 h, the products were analyzed using MLB and TAT broth. The enumeration of the cells was performed on B. cereus group selective plates Bacillus cereus rapid agar (BACARA) and Mannitol Yolk Polymyxin (MYP) plates. Results: No statistical difference (p > 0.05) was found for the recovery of cells from the liquid products using either medium (MLB or TAT broth) and the selective plates. In solid/powder products, a combination of Tween 80 and MLB detected significantly more cells (p < 0.05) than combination of Tween 80 and TAT broth. The microbial counts on BACARA showed no significant differences (p > 0.05). However, when assessing cream/oil-based products, the number of cells detected by use of Tween 80/TAT broth was significantly higher than Tween 80/MLB, and MYP showed significantly higher counts than BACARA. Conclusions: This study showed that relative effectiveness of MLB vs. TAT for recovering of B. cereus group cells varied depending on the variety of formulation, and combination of preservatives of the tested cosmetic products. The findings suggest additional studies are needed to explore recovery of other relevant microorganisms that may contaminate cream/oil-based cosmetics.