It's not just herbalists from Asia who have been using fermentation processes for their purposes for thousands of years. Our ancestors in the Western world also used the principle and refined their herbal products.
Fermentation is an enzymatic conversion process.
Herbs are broken down with the help of valuable microorganisms and converted into useful substances such as enzymes, amino acids, vitamins as well as bioactive substances and antioxidants. Fermentation processes only work with natural raw materials.