Unveiling the Microbial World: Understanding Staphylococcaceae Bacteria in Cosmetics

December 26, 2023 by
Sitra Muhiadin


In the vast microscopic realm, bacteria belonging to the Staphylococcaceae family stand out as intriguing organisms. Facultative anaerobes, gram-positive, and immobile with no spores, these cocci cluster together, presenting unique characteristics. This blog post delves into the significance of identifying these bacteria, their enrichment, isolation, and key biochemical tests for confirmation.

Enrichment and Blocking

Ensuring the health and well-being of consumers is paramount, making the identification of Staphylococcaceae bacteria in cosmetic products crucial. To achieve this, a meticulous enrichment and blocking process is recommended. Utilizing 1 ml/g of the sample with 9 ml of Eugon LT 100 Broth (CAT. 2110) facilitates the incubation at 32.5 oC ± 2 oC for 20 to 72 hours. Other enrichment broths, such as Dey-Engley Neutralizing Broth (CAT. 2003) and Letheen Broth Modified (CAT. 1244), can also be employed for a comprehensive analysis.

Presumptive Isolation

Baird Parker Agar (CAT. 1100 + CAT. 5129) serves as the medium for presumptive isolation, fostering the growth and identification of Staphylococcaceae bacteria. Incubating at 32.5 oC ± 2 oC for 24 to 48 hours, this step provides a crucial foundation for subsequent analyses. Alternative culture media like Mannitol Salt Agar (CAT.1062) and Vogel-Johnson Agar (CAT. 1079) are also acknowledged in industry standards.

Reading the Results

Distinctive colonies emerge on Baird Parker Agar (CAT. 1100),  showcasing a brilliant black color surrounded by a clear zone measuring 2 – 5 mm. This visual cue is pivotal in determining the presence and characteristics of Staphylococcaceae bacteria in the tested sample.

Biochemical Tests

To further confirm the identity of Staphylococcaceae bacteria, several biochemical tests are conducted on well-separated colonies. The Gram stain reveals Gram-positive cocci grouped in clusters, providing an initial classification. Subsequent tests, including the Catalase Assay (+) and Coagulase Test (+), serve as confirmatory proofs, solidifying the identification process.


The world of bacteria is complex, and the Staphylococcaceae family adds a layer of intricacy, especially in cosmetic products. By following a meticulous protocol involving enrichment, isolation, and biochemical tests, manufacturers and regulatory bodies can ensure the safety and quality of their products. Understanding the significance of each step and the utilization of specific culture media, such as CAT. 1100 and CAT. 1079, empowers the industry to uphold rigorous standards, ultimately benefiting consumers worldwide.


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Bustos-Martínez JA, Hamdan-Partida A, Gutiérrez-Cárdenas M. Staphylococcus aureus: la reemergencia de un patógeno en la comunidad. Rev Biomed. 2006 oct-dic; 17(4): 287-305. 

UNE-EN-ISO 22718:2015. Cosmetics. Microbiology. Detection of Staphylococcus aureus.

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