Abstract
Medicinal plants are plants that contain certain substances, certain healing compounds. Medicinal herbs are best used for prevention rather than treatment.This work aims to study the values of total phenolic content present in Calendula officinalis, Ginkgo biloba, Lycopodium clavatum, Equisetum arvense and in the tinctures. Their content will also be studied according to the storage period in order to signal any changes that may have occurred. The risks that can appear in the production of tinctures must be taken into acount. They could be of chemical nature, biological nature, physical nature. We mention here pieces of soil, plant debris, dust particles, pesticides, heavy metals, patogenic bacteria, fungi. Preventing the contamination of major tinctures relies on several methods: maintaining proper sanitation, using a high concentration of alcohol, and ensuring optimal humidity.