Chemical composition and bioactivity of essential oils of Hypericum helianthemoides, Hypericum perforatum and Hypericum scabrum.
BACKGROUND
A number Hypericum species are well known for their therapeutic efficacy and use in traditional medicine. The various species of Hypericum have been traditionally used for the treatment of wounds, eczema, burns, trauma, rheumatism, neuralgia, gastroenteritis, ulcers, hysteria, bedwetting and depression.


OBJECTIVE
This study evaluated the in vitro antioxidant, antibacterial and phytochemical properties of essential oils of Hypericum helianthemoides (Spach) Boiss., Hypericum perforatum L. and Hypericum scabrum L. (Hypericaceae) collected from alpine region of Southwest Iran.


METHODS
The essential oils obtained from dried flowering aerial parts of three Hypericum species were analyzed by gas chromatography and gas chromatography/mass spectrometry to determine chemical compositions. The antibacterial activity of essential oils within concentration ranges from 16 to 500 µg/mL was individually evaluated against Bacillus cereus, Listeria monocytogenes. Proteus vulgaris and Salmonella typhimurium. The 1,1-diphenyl-2-picrilhydrazyl (DPPH) radical scavenging activity of essential oils was determined using DPPH assay.


RESULTS
Essential oil yield of H. helianthemoides. H. scabrum and H. perforatum were 0.12, 0.20 and 0.21 mL/100 g dried material, respectively. The major constituents of the essential oils were α-pinene (12.52-49.96%), β-pinene (6.34-9.70%), (E)-β-ocimene (4.44-12.54%), β-caryophyllene (1.19-5.67%), and germacrene-D (2.34-6.92%). The essential oils of three Hypericum species indicated moderate-to-good inhibitory activities against four bacteria, especially against L. monocytogenes.


CONCLUSIONS
The essential oils of the three studied Hypericum species sourced in alpine region of West Iran were rich in monoterpene and sesquiterpenes hydrocarbons. Among the three tested species, the essential oil of H. scabrum showed the highest antibacterial and antioxidant activities.
Department of Medicinal Plants, Shahrekord Branch, Researches Center of Medicinal Plants & Ethno-veterinary, Islamic Azad University , Shahrekord , Iran .
Abdollah
A
Ghasemi Pirbalouti
Maryam
M
Fatahi-Vanani
Lyle
L
Craker
Hamzeali
H
Shirmardi
D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D035264:Flowers; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D020902:Hypericum / Q000737:chemistry*; D007492:Iran; D009822:Oils, Volatile / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D013045:Species Specificity
D000900:Anti-Bacterial Agents; D000975:Antioxidants; D016166:Free Radical Scavengers; D009822:Oils, Volatile; D010936:Plant Extracts