Anisic acid is a powerful antimicrobial agent against yeasts and moulds with a skin-neutral pH value of pH 5.5.
Obtained from star anise, our Cosphaderm® pAS natural from 100 % natural and sustainable sources and it is COSMOS-approved. In addition to its excellent antimicrobial properties, anisic acid is mild, skin-friendly and odourless. It is therefore also the first choice for baby care products.
In this video we show all the outstanding properties and the easy incorporation of this powerful natural multifunctional:
How does anisic acid work and what is the easiest way to incorporate it?
The acid is able to penetrate the membrane of yeasts and moulds and lower the internal pH value, which ultimately leads to cell death. Anisic acid makes the cosmetic product really unpleasant for germs and at the same time attractive to consumers.
At lower pH values, such as less than pH 5.5, anisic acid can crystallise. This is a problem because the acid has an antimicrobial effect in this range.
The key is the balance between acid and its salt. This means that the higher the pH value, the better the water solubility, because the higher the pH value, the higher the concentration of its salt, but the worse its antimicrobial efficacy.
To ensure that the anisic acid remains in solution, we stir in the anisic acid while heating it to around 50 °C. By adding diluted NaOH solution, we increase the pH value to around pH 9-10 and thus improve the solubility of the anisic acid. At this high pH value, the acid is now mainly present as anisate and thus dissolved.
However, in order to reach the antimicrobial effective range, i.e. the range in which the anisic acid is again present as a free acid, we must lower the pH value.
We avoid recrystallisation of the acid when lowering the pH value by slowly and carefully adding diluted HCl solution (1 %) or diluted citric acid (20 %) until we reach the pH value of pH 5.5, which corresponds to our target value.
With this simple trick, we can improve the solubility so that easy incorporation is possible and crystallisation is prevented. And with this special incorporation Cosphaderm® pAS natural can be used in practically any cosmetic formulation.
To additionally protect the cosmetic product from bacteria, we recommend combining it with levulinic acid, such as our Cosphaderm® LA-T.
