STABILITY OF SOME BIOLOGICALLY ACTIVE SUBSTANCES IN EXTRACTS AND PREPARATIONS BASED ON ST. JOHN'S WORT (HYPERICUM PERFORATUM L.) AND SAGE (SALVIA OFFICINALIS L.)

Quality, authenticity and stability control of medicinal plant materials and preparations based on them is an important challenge in industries using substances and materials derived from plants. St. John's wort (Hypericum perforatum L.) and sage (Salvia officinalis L.) are one of the most common and best-selling medicines in the world. They are composed of phloroglucinols and diterpenes possessing pharmacological properties. However, some of the compounds (hyperforin, carnosic acid, etc.) determining these qualities decompose under the influence of various physical and chemical factors with the formation of stable and unstable intermediates. Considering the importance of utilization of these plants, the stability of hyperforin, carnosic acid and other compounds in their extracts and preparations during extraction and storage was studied in this work. Extracts and preparations were studied by high performance liquid chromatography (HPLC) with diode-array and mass spectrometric detection. Plant extracts were obtained by heating (HE) as well as using ultrasonic (USE), microwave (MWE) and supercritical (SSE) extraction. The stability of hyperforins, their degradation, as well as the relationship between hyperforin and furohyperforin contents in extracts and preparations based on H. perforatum L. during storage were studied. Hyperforin to furohyperforin ratio in the extracts ranged from 18 to 5 depending on the origin of the medicinal plant material. The stability and transformation of carnosic acid was evaluated, the relationship between carnosic acid and carnosol contents and conditions of sample preparation and storage as well as industrially manufactured preparations based on S. officinalis L. was revealed. The possibility of applicability of hyperforin to furohyperforin ratio in H. perforatum L. and carnosic acid to carnosol ratio in S. officinalis L. was shown to confirm the quality of extracts and preparations on their basis. Since rutin to hyperforin ratio in H. perforatum L. is constant, this indicator can be used to confirm the quality and authenticity of the feedstock, regardless of where the plant grows.