Details of the in vitro experiment

On this page you will find detailed charts summarizing the results obtained during the experiment conducted by the Department of Pharmacological and Biomolecular Sciences of the University of Milan.

The purpose of the experiment was to determine whether the tannins present in vegetable tanned leather can act as an effective weapon against bacteria.

The experiment was conducted in vitro and involved samples of leather with different types of vegetable tannins (Chestnut, Quebracho and Tara), samples of chrome tanned leather and one sample of synthetic material.

The results confirmed that the tannin contained in the vegetable tanned leather can counteract the antibacterial activity.

The study was conducted entirely in a laboratory and involved 6 different materials

3 samples of vegetable tanned leather with different types of vegetable tannins (Chestnut, Quebracho, Tara).

1 sample of chrome tanned leather.

1 sample of chrome tanned leather, then retanned with vegetable tannins.

1 sample of synthetic lining.

2 species of bacteria:

Escherichia coli

Gram negative

Staphylococcus aureus

Gram positive

Results of the Experiment

Vegetable Tanning with Tannin

Bacteria Reduction at Time Zero

Gram +

%

Gram –

%

Bacteria Reduction After 6 hours

Gram +

%

Gram –

%

Chrome Tanning

Bacteria Reduction at Time Zero

Gram +

%

Gram –

%

Bacteria Reduction After 6 hours

Gram +

%

Gram –

%

Chrome Tanning, Vegetable Retanning

Bacteria Reduction at Time Zero

Gram +

%

Gram –

%

Bacteria Reduction After 6 hours

Gram +

%

Gram –

%

Synthetic Material

Bacteria Reduction at Time Zero

Gram +

%

Gram –

%

Bacteria Reduction After 6 hours

Gram +

%

Gram –

%

Vegetable Tanned Leather: Breathable and Comfortable

Thanks to the properties shown during the above mentioned experiment, tannin finds concrete applications in our daily life. Especially inside our shoes, tannin imparts to the vegetable tanned leather good breathable properties, thus creating an environment that is not suitable for bacterial proliferation and avoiding the formation of bad shoe odors.