Fatih Seyis

Secondary metabolites of seven Hypericum species growing in Turkey

Abstract Context The genus Hypericum (Hypericaceae) has attracted remarkable scientific interest as its members have yielded many bioactive compounds. Objective The current study presents investigations on the accumulation of hypericin, pseudohypericin, hyperforin, adhyperforin, chlorogenic acid, neochlorogenic acid, caffeic acid, 2,4-dihydroxybenzoic acid, 13,118-biapigenin, hyperoside, isoquercitrin, quercitrin, quercetin, avicularin, rutin, (+)-catechin and (−)-epicatechin in seven Hypericum (Hypericaceae) species growing wild in Turkey, namely, H. aviculariifolium Jaup. and Spach subsp. aviculariifolium (Freyn and Bornm.) Robson var. albiflorum (endemic), H. bithynicum Boiss., H. calycinum L., H. cardiophyllum Boiss., H. elongatum L. subsp. microcalycinum (Boiss. and Heldr.) Robson, H. hirsutum L. and H. xylosteifolium (Spach) N. Robson. Materials and methods The plant materials were collected at flowering period and dissected in different tissues. Air-dried plant material including stems, leaves and flowers was mechanically powdered with a laboratory mill and samples (0.1 g) were extracted in 10 mL of 100% methanol by ultrasonication at 40 °C for 30 min for HPLC-PDA analyses. Results Accumulation levels of the investigated compounds varied greatly depending on species and plant part. Discussion For the first time, the detailed chemical profiles of corresponding Turkish Hypericum species were reported and the results were discussed from a phytochemical point of view. Conclusions The present data have importance in evaluation of plant resources of Hypericum genus in selecting the new potential sources of bioactive compounds.

Antimicrobial and Antioxidant Activity of the Essential Oil of the Turkish Endemic Species Achillea phrygia Boiss. & Bal.

Abstract The essential oil obtained from the dried flowering aerial parts of Achillea phrygia Boiss & Bal. by hydrodistilation was analysed by gas chromotography-mass spectrometry. Camphor (35.55 %), 2- furaldehyde (16.59 %) and 1,8-cineol (eucalyptol) (10.12 %) were detected as the major components of the essential oil. Essential oil of the plant was also tested for antimicrobial activity using the disc-diffusion method against 6 reference bacterial strains and 65 clinical bacterial isolates. Essential oil of A. phrygia showed antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA), methicillin-sensitive S. aureus (MSSA), Acinetobacter baumannii and bacterial strains as S. aureus ATCC 25923, S. aureus ATCC 43300, Acinetobacter baumannii ATCC 19606. In additionally, the essential oil were not effective against bacterial strains as Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 29212. Morover, the total antioxidant capacity and the scavenging effect on 2,2diphenil-1-picrylhydrazyl (DPPH) radicals of the essential oil were also evaluated. The radical scavenging activity of A. phrygia essential oil was 40.43 %.

Chemical Composition and Antimicrobial Activity of the Essential Oil of Endemic Heracleum platytaenium Boiss. from Turkey

The compositions of the essential oil of Heracleum platytaenium Boiss. aerial parts, grown in Turkey were determined by GC-MS. Twenty-two compounds (95.24 %) were determined. The major compounds in the oil were found to be octyl acetate (85.53 %), octyl hexanoate (3.06 %), (Z)-4-octenyl acetate (1.60 %) and octyl octanoate (1.24 %). The antimicrobial activity of essential oil extracted from H. platytaenium against various yeast and bacteria species using the disc diffusion method was investigated during the present study. The extract exhibited strong antimicrobial activity against Candida glabrata with inhibition zones varying between 12-32 mm. In contrast, the growth of all the tested bacteria were not affected by the extract. In conclusion, this study confirms that H. platytaenium essential oil could be considered as a natural anticandidal source.