Plants are natural sources of bioactive compounds, and the intensive use of wild plants to obtain them, in particular secondary metabolites, depletes natural biocenoses. Instead, modern biotechnological methods, especially cell and tissue culture in vitro, make it possible to get environmentally friendly, highly productive plant raw materials that are able to synthesize and accumulate specialized substances, which are valuable for pharmacology, cosmetology, and medicine. Regenerating in vitro-plants of different plant species such as Acorus calamus L., Phalaenopsis sp., and Salvia hispanica L. were obtained in our research. It was proved that by changing the cultivation conditions it is possible to change the content of substances of secondary metabolites in explants and in the nutrient medium under aseptic culture.