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The volatile constituents of the rare species of Hypericum, namely Hypericum pruinatum (as one population) and Hypericum aviculariifolium subp. depilatum var. depilatum (endemic, as two populations namely 'Gümüş' and 'Yeniköy') growing wild in the mountainous parts of Northern Turkey were studied for the first time. The essential oils (EOs) were extracted by hydrodistillation of the air-dried aerial parts and analysed by GC-FID and GC-MS. A total of 56, 49 and 50 EO components representing 98.2%, 96.9% and 99.4% of the total composition were identified respectively from one population for H. pruinatum and two populations for Hypericum aviculariifolium subp. depilatum var. depilatum. GC-MS profiles showed significant compositional variations not only between the two Turkish species, but also between the two populations of the same species highlighting the importance of genetic factors affecting secondary metabolite profile.

Context: Hypericum perforatum L. (Guttiferae) contains many bioactive secondary metabolites including hypericins, hyperforins, and essential oil., Objective: The present study was conducted to determine the variation in composition of essential oil in H. perforatum accessions from Turkey., Material and Methods: At full flowering, aerial parts of 30 plants were collected from 10 sites of northern Turkey and assayed for essential oil components by GC-FID and GC-MS., Results: The chemical analysis revealed that the main constituents of the all analyzed samples were hydrocarbon and oxygenated sesquiterpenes such as beta-caryophyllene (4.08-5.93%), gamma-muurolene (5.00-9.56%), beta-selinene (5.08-19.63%), alpha-selinene (4.12-10.42%), d-cadinene (3.02-4.94%), spathulenol (2.34-5.14%), and caryophyllene oxide (6.01-12.18%). Monoterpenes, both hydrocarbon and oxygenated, were represented by scarce amounts of alpha- and beta-pinene, myrcene, linalool, cis- and trans-linalool oxide, and alpha-terpineol. Principal component analysis was also carried out and, according to the results, the first nine principal components were found to represent 100% of the observed variation., Discussion: The chemical variation among the populations is discussed as the possible result of different genetic and environmental factors., Conclusions: The wild populations examined here are potentially important sources for breeding and improvement of the cultivated varieties.

A wild strain of Agrobacterium rhizogenes was used to regenerate twelve in vitro plant lines from different hairy roots of H. perforatum (St. John's Wort). The production of the main bioactive constituents was observed even though their yields varied in the different plant lines. Two lines were selected for the hyperoside production (4.9-4.6 mg/gdw) while nine were characterized by significant yields of chlorogenic acid (ranged from 0.47 to 1.09 mg/gdw). Furthermore, one out of twelve lines showed a 10-fold higher hypericin content (0.25 mg/gdw) than that reported for the in vitro shoots in the literature. Morphological and phytochemical features were determined in order to select H. perforatum genotypes enriched in valuable bioactive compounds.

Five extracts and pure compounds from the aerial parts of Hypericum triquetrifolium were tested for their antibacterial activity against 31 gram-positive and gram-negative strains using the agar dilution method (Lorian). The ethyl acetate extract exhibited a weak antibacterial activity against Staphylococcus strains, and pure constituents such as quercetin and I3,II8-biapigenin were the active components of this extract., (Copyright 2005 John Wiley & Sons, Ltd.)

The genus Hypericum (Guttiferae) is one of the most representative species in temperate zones and Turkey is one of the most important Mediterranean sites. Due to the increasing commercial value of Hyperici herba ( Hypericum perforatum ), many wild Turkish Hypericum species have received currently a considerable renewed interest as potential substitutes of the well-established H . perforatum crops for their similar content in the standardization bioactives (hypericins, hyperforins, and flavonoids). The present paper reported the volatile fingerprints of three selected wild Turkish Hypericum species recently characterized as H . perforatum bioactive-like profiles but lacking of the requested well-established usage in the EU market. In this context, the volatile constituents of the three-selected Hypericum spp. were investigated as additional discriminating markers to enhance the likelihood that this adulterating plant raw material will be detected before it is incorporated into finished H . perforatum products. [ABSTRACT FROM AUTHOR]

Turkish Hypericum origanifolium Willd has been recently considered for its hypericin and phenolic content as a potential substitute of the well-established EU market position Hypericum perforatum . However, a complete phytochemical characterization of H. origanifolium has not carried out yet in order to assert its potential industrial value. The present paper represents the first attempt to define the aromatic fingerprint of a representative wild Turkish H. origanifolium Willd. population. In addition, its volatiles were studied as potential discriminating constituents between H. perforatum and H. origanifolium with a similar hypericin and phenolic composition. [ABSTRACT FROM AUTHOR]

Context: Hypericum perforatum L. (Guttiferae) contains many bioactive secondary metabolites including hypericins, hyperforins, and essential oil. Objective: The present study was conducted to determine the variation in composition of essential oil in H. perforatum accessions from Turkey. Material and methods: At full flowering, aerial parts of 30 plants were collected from 10 sites of northern Turkey and assayed for essential oil components by GC-FID and GC-MS. Results: The chemical analysis revealed that the main constituents of the all analyzed samples were hydrocarbon and oxygenated sesquiterpenes such as β-caryophyllene (4.08–5.93%), γ-muurolene (5.00–9.56%), β-selinene (5.08–19.63%), α-selinene (4.12–10.42%), -cadinene (3.02–4.94%), spathulenol (2.34–5.14%), and caryophyllene oxide (6.01–12.18%). Monoterpenes, both hydrocarbon and oxygenated, were represented by scarce amounts of α- and β-pinene, myrcene, linalool, cis- and trans-linalool oxide, and α-terpineol. Principal component analysis was also carried out and, according to the results, the first nine principal components were found to represent 100% of the observed variation. Discussion: The chemical variation among the populations is discussed as the possible result of different genetic and environmental factors. Conclusions: The wild populations examined here are potentially important sources for breeding and improvement of the cultivated varieties. [ABSTRACT FROM AUTHOR]