Abstract

The present study is aimed at investigating the effects of variation in secondary metabolites of St. John’s wort for its better use as an antibiotic. The seasonal dynamics investigation of St. John’s wort secondary metabolites was carried out on annual, biennial and triennial wild-growing plants of the suburban localities, and on the indigenous perennial plants of the mountainous localities. The effects of variation in secondary metabolites of the plant material were monitored using a complex antimicrobial preparation imanin. As plant secondary metabolites, imanin was isolated from flowers and leaves of St. John’s wort by aqueous-alkaline extraction. The quality of imanin contained in St. John’s wort was determined by FTIR and HPLC methods. The imanin extracts were tested for antimicrobial activity against Staphylococcus aureus, Streptococcus agalactiae,Bacillus diphteriae, Bacillus tetani, Clostridium histolyticus, Bacillusmesentericus and Bacillus mycoides. The quantitative effects of temperature and light intensity on imanin accumulations in St. John’s wort were examined depending on the sampling periods and location. The results of antimicrobial activity and quantitative effects of climatic conditions were correlated with vegetation phases of hypericum plants.

Key words: Imanin, St. John’s wort, antimicrobial activity, hyperforin, plant vegetation.