MyMicrobiome Standard 22.10 – Foot microbiome

This test guarantees the microbiological purity of the foot care product. It is examined for contamination by mesophiles and aerobic microorganisms, i.e. bacteria, yeasts or molds (TAMC and TYMC). The limit value is ≤ 1 x 10 ³ cfu/g or ml and is therefore very strict.

A co-culture is grown with the most common skin microbes S. epidermidis and the harmful bacteria S. aureus. The co-culture is then exposed to the product for a specified period of time and then compared to an untreated control group. The balance must not be tipped in favor of S. aureus under the influence of the product.

In this step, microbes typically found in the foot microbiome are cultured in our lab (S. hominis, S. warneri, S. epidermidis, M. luteus, M. globosa, C. Tuberculostearicum). A co-culture is exposed to the product to be tested and the change in diversity then compared to the untreated control group. The diversity of the foot microbiome must be preserved with regard to the most important key microbes.

A Microbiome-friendly foot product must both preserve diversity and, importantly, pose no detrimental effects to microbial growth. The test simulates skin contact by using a model. First, each key microbe is brought in direct contact with the foot care product; Then, the microbe is covered with an agar layer and the product to be tested is applied to this layer. This simulates the potential penetration of the care product into the deeper layers of the skin. As always, the cell growth of the two batches is compared with the untreated control group; the growth must not be significantly inhibited.