Essential oil composition ofHypericum perfoliatum L. growing in different locations in Greece

Essential Oil Composition of Seven Bulgarian Hypericum Species and Its Potential as a Biopesticide

Hypericum species and especially H. perforatum L. are well known for their therapeutic applications. The present study assessed the essential oil (EO) composition, and antifungal and aphid suppression activity of seven Bulgarian Hypericum species. The EOs were analyzed by GC-MS-FID. Two experiments were conducted. In the first experiment, H. perforatum, H. maculatum, and H. hirsutum were used. Additionally, the EO composition of H. perforatum extracted via hydrodistillation (ClevA) and via commercial steam distillation (Com) were compared. The second experiment compared the EOs of H. perforatum, H. cerastoides, H. rumeliacum, H. montbretii, and H. calycinum (flowers and leaves) extracted via hydrodistillation and collected with n-hexane. Overall, the EO constituents belonged to four classes, namely alkanes, monoterpenes, sesquiterpenes, and fatty acids. The main class for compounds in H. maculatum and H. perforatum (section Hypericum) were sesquiterpenes for both experiments except for H. perforatum (Com). Hypericum montbretii (section Drosocarpium) EO had monoterpenes (38.09%) and sesquiterpenes (37.09%) as major groups, while H. hirsutum EO (section Taeniocarpium) contained predominately alkanes (67.19%). Hypericum hirsutum EO contained cedrol (5.04%), found for the first time in Hypericum species. Fatty acids were the main compounds in H. cerastoides (section Campylopus), while monoterpenes were the most abundant class in H. rumeliacum and H. calycinum EOs. α-Pinene and germacrene D were the major EO constituents of all analyzed Hypericum species except for H. hirsutum and H. cerastoides. Hypericum perforatum EO (Com) had significant repellent and insecticidal activity against two aphid species, Rhopalosiphum padi (Bird Cherry-oat aphid) and Sitobion avenae (English grain aphid) at concentrations of 0%, 1%, 2.5%, 3.5%, 4.5%, and 5%. The tested EOs did not show significant activity against selected economically important agricultural fungal pathogens Fusarium spp., Botrytis cinerea, Colletotrichum spp., Rhizoctonia solani, and Aspergillus sp. The EO of the Hypericum species found in the Bulgarian flora could be utilized for the development of new biopesticides for aphid control.

Chemical Composition and New Biological Activities of Essential Oil and Hydrosol of Hypericum perforatum L. ssp. veronense (Schrank) H. Lindb

The chemical profile, antiproliferative, antioxidant and antiphytoviral activities of the species Hypericum perforatum ssp. veronense (Schrank) H. Lindb. (Clusiaceae) were investigated. Free volatiles were isolated and the chemical composition was determined in the lipophilic fraction (essential oil) and for the first time in the water fraction (hydrosol). The aim is to provide phytochemical data for H. perforatum ssp. veronense useful for distinguishing ssp. veronense from ssp. angustifolium, as there are taxonomic disagreements between them and the composition of the secretory products may be helpful in this respect. In the essential oil, the most abundant compounds identified were α-pinene and n-nonane, while in the hydrosol, myrtenol, carvacrol and α-pinene were the most abundant. Overall, the class of monoterpenes and oxygenated monoterpenes dominated in the EO and hydrosol samples. The essential oil showed high antioxidant activity, in contrast to the antiproliferative activity, where the hydrosol showed exceptional activity against three cancer cell lines: Hela (cervical cancer cell line), HCT116 (human colon cancer cell line) and U2OS (human osteosarcoma cell line). Both the essential oil and hydrosol showed antiphytoviral activity against tobacco mosaic virus infection on the local host plants. This is the first report dealing with biological activities of hydrosol of H. perforatum ssp. veronense, and the obtained results suggest that this traditional medicinal plant is a valuable source of volatiles with promising antiproliferative, antioxidant and antiphytoviral activities.

Metabolomic fingerprinting and genetic discrimination of four Hypericum taxa from Greece

Hypericum perforatum has plenty of uses in traditional medicine and is the source of top-selling herbal drugs and food supplements. The secondary metabolite chemistry for most of the nearly 500 Hypericum taxa is still unknown, even though they are used interchangeably. In the present study, we characterized four Hypericum populations from Achaia, Greece, belonging to H. perforatum ssp. veronense, H. perfoliatum, H. triquetrifolium, and an uninvestigated taxon, H. empetrifolium ssp. empetrifolium, in terms of their essential oils and polar bioactives in methanolic extracts via GC-MS, LC-HRMS, LC-DAD-MS, and HPLC-DAD. We also performed sequence analysis of nrITS to explore the genetic profile of these taxa and to examine whether their genotype is correlated to the metabolome. Sixty-three non-volatile compounds, phloroglucinols in their majority, and over one hundred (113) volatiles, mostly sesqui- and mono- terpenes, were detected. The concentration of the major polar constituents varied greatly among samples. In particular, phloroglucinols' diversity and abundance in H. empetrifolium ssp. empetrifolium was remarkable. The PCA and Biplot analysis revealed the contribution of each compound to the total chemodiversity and also revealed certain compounds that contribute to the discrimination of the samples. Sequence analysis of nrITS revealed different genetic profiles and markers which can be used for the identification of the four Hypericum taxa. The Mantel test showed a relatively strong correlation between the genetic profile and the volatile compounds and low with the main polar metabolites.

Chemical Composition and Antimicrobial Activity of the Essential Oils of Three Closely Related Hypericum Species Growing Wild on the Island of Crete, Greece

The volatile compositions of three closely related Hypericum species growing wild on the island of Crete were studied, all belonging to the section Coridium. Hydro-distillation in a modified Clevenger-type apparatus was performed according to the Hellenic Pharmacopoeia in order to obtain the essential oils, which were analyzed by GC-MS. Identification of the compounds was carried out by comparison of MS spectra and retention indices with literature data, as well as by co-chromatography with authentic samples. In total, 123 different compounds were identified and the main compounds were by order of their abundance as follows: H. empetrifolium: α-pinene, germacrene D, β-pinene, E-caryophyllene; H. amblycalyx: β-elemene, β-selinene, α-pinene, E-caryophyllene, α-selinene; H. jovis: trans-calamenene, α-selinene, β-elemene. The chemical results revealed the differences and similarities (qualitative and quantitative) between the studied oils, supporting the hypothesis that essential oils from Hypericum spp. do not serve as chemotaxonomic markers. Moreover, the essential oils were subjected to antimicrobial screening. According to the given results, the essential oils possessed better antifungal and anticandidal activities than antibacterial activities.

Bioactive compounds from Hypericum humifusum and Hypericum perfoliatum: inhibition potential of polyphenols with acetylcholinesterase and key enzymes linked to type-2 diabetes

CONTEXT

Natural products are reported to have a wide spectrum of pharmacological properties such as antimicrobial, anti-inflammatory and anti-cholinesterase. The genus Hypericum (Hypericaceae) is a source of a variety of molecules with different biological activities, notably hypericin and various phenolics.

OBJECTIVES

The goals of the present work were the determination of total phenolic and flavonoid content, hypericin and hyperforin concentration as well as the evaluation of biological of Hypericum humifusum L. (Hhu) and Hypericum perfoliatum L. (Hper).

MATERIALS AND METHODS

The various extracts of aerial parts were powdered, and then extracted with methanol. Antibacterial activity was performed according to minimum inhibitory concentration (MIC) and minimum bactericidal (MBC) methods against four Gram-positive bacteria, four Gram-negative bacteria and yeast.

RESULTS

The results revealed that H. humifusum, bear the highest total phenolic and flavonoid content (48-113 mg GAE/g and 8-41 mg RE/g, respectively) as well as hypericin (60-90 mg/g) and hyperforin (8-30 mg/g) concentration. Both species showed significant antioxidant activity as revealed by DPPH, FRAP, ABTS, and metal chelating assays. H. humifusum exhibited a strong acetylcholinesterase (3.86-4.57 mg GALAEs/g), α-glucosidase (0.73-2.55 mmol ACEs/g) and α-amylase (3-8 mmol ACEs/g) inhibitory activity. The extract of H. humifusum exhibited strong antibacterial activity mainly against Staphylococcus epidermidis, Staphylococus aureus, and Enterococcus faecium (MIC values ranging from 200 to 250 μg/mL). The highest antifungal activity was showed for H. perfoliatum extract (MIC value = 250 μg/mL).

CONCLUSION

The data suggest that H. humifusum could be used as valuable new natural agents with functional properties for pharmacology industries.

Chemical composition and antioxidant activities of the essential oil of Hypericum gaitii Haines - an endemic species of Eastern India

The present study reports the chemical composition and antioxidant activities of the essential oil extracted from the leaves and tender branches of Hypericum gaitii Haines (Hypericaceae) - an endemic plant of Eastern India. On hydrodistillation, the fresh leaves and tender parts of H. gaitii yielded 0.43% (v/w) of pale yellowish essential oil. Gas chromatography mass spectrometry analysis revealed the presence of 40 compounds, which represent 96.9% of the total oil. Monoterpene hydrocarbons (79.3%) predominated followed by sesquiterpene hydrocarbons (12.6%). Of these, α-pinene (69.5%), β-caryophyllene (10.5%), sabinene (5.6%), myrcene (3.0%) and geranyl acetate (2.0%) were the main constituents. Antioxidant activities of oil were evaluated by three different systems namely 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and reducing power assay. Essential oil exhibited moderate antioxidant activities compared to butylated hydroxytoluene (BHT) and ascorbic acid.

Phenolic and Volatile Composition of a Dry Spearmint (Mentha spicata L.) Extract

The present paper reports a complete mass spectrometric characterization of both the phenolic and volatile fractions of a dried spearmint extract. Phenolic compounds were analysed by ultra-high performance liquid chromatography-electrospray ionization-mass spectrometry (UHPLC-ESI-MS(n)) and a total of 66 compounds were tentatively identified, being the widest phenolic characterisation of spearmint to date. The analysis suggests that the extract is composed of rosmarinic acid and its derivatives (230.5 ± 13.5 mg/g) with smaller amounts of salvianolic acids, caffeoylquinic acids, hydroxybenzoic acids, hydroxycinnamic acids, flavones, and flavanones. Head space solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) technique, that was applied to characterize the volatile fraction of spearmint, identified molecules belonging to different chemical classes, such as p-cymene, isopiperitone, and piperitone, dihydroedulan II, menthone, p-cymen-8-ol, and β-linalool. This comprehensive phytochemical analysis can be useful to test the authenticity of this product rich in rosmarinic acid and other phenolics, and when assessing its biological properties. It may also be applied to other plant-derived food extracts and beverages containing a broad range of phytochemical compounds.

Chemical composition and bioactivity of essential oils of Hypericum helianthemoides, Hypericum perforatum and Hypericum scabrum

CONTEXT

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.

MATERIALS AND 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.

DISCUSSION AND CONCLUSION

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.

The case of Hypericum rochelii Griseb. & Schenk and Hypericum umbellatum A. Kern. essential oils: chemical composition and antimicrobial activity

The chemical composition and antimicrobial activity studies on the essential oils of Hypericum rochelii Griseb. & Schenk and Hypericum umbellatum A. Kern. have been carried out for the first time. Seventy-nine compounds were identified in the essential oil of H. rochelii with n-nonane (24.7%), β-pinene (22.4%), germacrene D (7.5%), n-undecane (6.8%) and α-pinene (5.8%) as main constituents. One hundred and twenty-six compounds were identified in H. umbellatum essential oil with germacrene D (6.1%), (E)-nerolidol (4.4%), n-nonane (4.0%), (E)-caryophyllene (3.0%) and caryophyllene oxide (3.0%) as the most abundant components. Both oils were characterized by the presence of many components which could have numerous applications in food, pharmaceutical and perfume industries. Taxa studied herein belong to the section Drosocarpium Spach, and their intrasectional placement based on the essential oil profiles was discussed. The oils were tested in a broth microdilution assay against five bacterial and two fungal strains and found to have mainly moderate antimicrobial effects.

Evaluation of the cytotoxic effect and antibacterial, antifungal, and antiviral activities of Hypericum triquetrifolium Turra essential oils from Tunisia

Background

A number of bio-active secondary metabolites have been identified and reported for several Hypericum species. Many studies have reported the potential use of the plant extracts against several pathogens. However, Hypericum triquetrifolium is one of the least studied species for its antimicrobial activity. The aim of the present study was to evaluate the cytotoxic effect of the essential oils of Hypericum triquetrifolium as well as their antimicrobial potential against coxsakievirus B3 and a range of bacterial and fungal strains.

Methods

The essential oils of Hypericum triquetrifolium harvested from five different Tunisian localities (Fondouk DJedid, Bou Arada, Bahra, Fernana and Dhrea Ben Jouder) were evaluated for their antimicrobial activities by micro-broth dilution methods against bacterial and fungal strains. In addition, the cytotoxic effect and the antiviral activity of these oils were carried out using Vero cell lines and coxsakievirus B3.

Results

The results showed a good antibacterial activities against a wide range of bacterial strains, MIC values ranging between 0.39-12.50 mg/ml and MBC values between 1.56-25.0 mg/ml. In addition, the essential oils showed promising antifungal activity with MIC values ranging between 0.39 μg/mL and 12.50 μg/mL; MFC values ranged between 3.12 μg/mL and 25.00 μg/mL; a significant anticandidal activity was noted (MIC values comprised between 0.39 μg/mL and 12.50 μg/mL). Although their low cytotoxic effect (CC₅₀ ranged between 0.58 mg/mL and 12.00 mg/mL), the essential oils did not show antiviral activity against coxsakievirus B3.

Conclusion

The essential oils obtained from Hypericum triquetrifolium can be used as antimicrobial agents and could be safe at non cytotoxic doses. As shown for the tested essential oils, comparative analysis need to be undertaken to better characterize also the antimicrobial activities of Hypericum triquetrifolium extracts with different solvents as well as their purified fractions and their pure secondary metabolites.

Chemical Composition and Possible in vitro Antigermination Activity of Three Hypericum Essential Oils

The essential oils of Hypericum perforatum, H. perfoliatum and H. hircinum, growing in Southern Italy, were analyzed by GC and GC/MS. In the three oils, 111 compounds in all were identified: 53 for the oil of H. hircinum (93.7% of the total oil), 55 for H. perforatum (96.5% of the total oil) and 63 for H. perfoliatum (98.7% of the total oil). The major fraction of the essential oils of H. perforatum and H. hircinum was represented by sesquiterpene hydrocarbons, while the monoterpene α-pinene, and the phenol thymol were the most abundant compounds in the essential oil of H. perfoliatum.

The oils were evaluated for their potential in vitro phytotoxic activity against germination and early radicle elongation of Raphanus sativus and Lepidium sativum. The germination of this latter was significantly inhibited by the essential oil of H. hircinum, at the highest doses tested, whereas radicle elongation of garden cress was significantly inhibited by the essential oils of H. perfoliatum and H. hircinum. The radicle elongation of radish was inhibited by the essential oil of H. hircinum to a major extent and by H. perforatum and perfoliatum in a minor measure.

Essential Oil and Volatile Components of the Genus Hypericum (Hypericaceae)

The flowering plant genus Hypericum (Hypericaceae) contains the well-known medicinally valuable species Hypericum perforatum (common St. John's wort). Species of Hypericum contain many bioactive constituents, including proanthocyanins, flavonoids, biflavonoids, xanthones, phenylpropanes and naphthodianthrones that are characterized by their relative hydrophilicity, as well as acylphloroglucinols and essential oil components that are more hydrophobic in nature. A concise review of the scientific literature pertaining to constituents of Hypericum essential oils and volatile fractions is presented.

Differential effects of three species ofHypericum in an open field test

The effects of three species of Hypericum (H.) on mice motor activity were compared in an automated open field test. Methanol extracts of H. perforatum L., H. hircinum L. and H. perfoliatum L. were tested at doses ranging from 2.5 to 200 mg i.p. H. hircinum decreased locomotion at most dose levels. Moreover, a dose of 200 mg/kg of all three herbal species sharply decreased motor activity. Ten mg/kg of H. perforatum, a dose that is comparable to that endowed with antidepressant effects in humans, tended to increase exploration and stereotypic activity and to decrease immobility. The study suggests that there are differences in the neuropharmacological actions of the three plant extracts. However, common constituents might explain the reduced motor activity observed at high dose levels.

Cloning, expression, purification and characterization of recombinant (+)-germacrene D synthase from Zingiber officinale

A cDNA clone encoding a sesquiterpene synthase, (+)-germacrene D synthase, has been isolated from ginger (Zingiber officinale). The full-length cDNA (AY860846) contains a 1650-bp open reading frame coding for 550 amino acids (63.8kDa) with a theoretical pI=5.59. The deduced amino acid sequence is 30-46% identical with sequences of other sesquiterpene synthases from angiosperms. The recombinant enzyme, produced in Escherichia coli, catalyzed the formation of a major product, (+)-germacrene D (50.2% of total sesquiterpenoids produced) and a co-product, germacrene B (17.1%) and a number of minor by-products. The optimal pH for the recombinant enzyme is around 7.5. Substantial (+)-germacrene D synthase activity is observed in the presence of Mg2+, Mn2+, Ni2+ or Co2+, while the enzyme is inactive when Cu2+ or Zn2+ is used. The Km- and kcat-values are 0.88 microM and 3.34 x 10(-3) s(-1), respectively. A reaction mechanism involving a double 1,2-hydride shift has been established using deuterium labeled substrates in combination with GC-MS analysis.

Compositions and antimicrobial activities of the essential oils of two Hypericum species from Turkey

The chemical compositions of essential oils obtained from Hypericum hyssopifolium var. microcalycinum and Hypericum lysimachioides var. lysimachioides were analysed by using GC and GC-MS. Caryophyllene oxide was found to be the major component. The essential oils of both Hypericum species showed antimicrobial activity against nine microorganism at a concentration of 60 to 80 microg/ml.

Essential oil composition of hypericum atomarium boiss

The essential oil of Hypericum atomarium Boiss. was analysed for the first time. Seven components were identified, accounting for 83.6% of the total oil. The three most abundant components (isocaryophyllene, y-cadinene and 2.4 diisopropenyl-i-methyl-i-vinyl-cyclohexane) represented 64.5% of the oil. A high content of sesquiterpenes (79.6%) characterized the oil.

Composition and antimicrobial activity of the essential oil of Hypericum rumeliacum subsp. apollinis (Boiss. & Heldr.)

The composition and the antimicrobial activity of the aerial parts of Hypericum rumeliacum are reported. Analysis was carried out by GC/MS. The major constituents were alpha-pinene (43.80%), beta-pinene (9.82%), dehydro-aromadendrene (6.81%) and alpha-copaene (5.41%). The essential oil showed a moderate in vitro activity against the six Gram negative and positive bacteria and a stronger one against the three-tested pathogenic activity.

Antioxidant activity of polyphenols from Hypericum triquetrifolium Turra

From the aerial parts of Hypericum triquetrifolium Turra (Guttiferae) 3-8"-biapigenin, quercetin, rutin and chlorogenic acid were isolated. Their structures were elucidated by spectral techniques. Furthermore, the phenolic compounds were tested for antioxidant activity, using an in vitro method based on sodium arachidonoate, bleomycin and thiobarbituric acid with alpha-tocopherol as the reference solution.