Abstract
St. John's wort (Hypericum perforatum) is a medicinal plant known for its bioactive compounds, including tocopherols and tocotrienols, which possess antioxidant and anti-inflammatory properties. These compounds play vital roles in the plant's metabolism and have potential applications in the cosmetic and pharmaceutical industries. However, the content of these compounds in different anatomical parts of the plant, as well as the influence of environmental factors, such as the year of collection, remain underexplored. This study examined the content of tocochromanols in H. perforatum leaves, flowers, and flower buds, collected in Poland during the years 2022-2024. The results revealed that tocopherols predominantly accumulated in the leaves, while tocotrienols were more abundant in the flowers and flower buds. The year of collection had a significant effect on tocopherol levels, while tocotrienol content showed lower sensitivity to environmental fluctuations, indicating their higher stability. St. John's wort can be considered a valuable source of biologically active compounds, especially tocotrienols, which exhibit higher stability and less susceptibility to environmental variability. The results underline the importance of considering both the plant's anatomical parts and the year of collection when aiming to maximize the production of bioactive compounds.