The Effects of Organic and Conventional Cultivation Systems on the Content of Bioactive Substances in Herbal Plants

Five species of herbs from organic and conventional cultivation (dropsy plant, lovage, mint, thyme and sage) were used for this experiment. The research material consisted of usable parts of fresh herbs, which were harvested in the first ten days of September 2009 and 2010. In order to avoid losses in the content of biologically active compounds in the plant material, the herbs were frozen at -80°C immediately after harvesting, and then subjected to freezedrying; finally, analytical research was conducted. The results of two-year studies indicated that herbal plants from organic production contained a higher level of dry matter, vitamin C and flavonoids, while the conventional ones contained more phenolic acids. Regardless of the cultivation system, dropsy plant and mint were distinguished by the content of phenolic acids, the highest level of flavonoids was found in thyme, while lovage was the raw material containing the most vitamin C. The qualitative analysis of phenolic compounds contained in herbs showed that the most diverse composition of phenolic acids was attributed to sage and thyme, which also contained the largest number of identified flavonoids.