Trends in Phenolic Profiles of Achillea millefolium from Different Geographical Gradients.

The traditional widely used raw material of Achillea millefolium is currently mainly derived from wild populations, leading to diversification and uncertainty in its quality. The aim of the study was to determine the accumulation differences of phenolic compounds between geographically distant populations of Achillea millefolium from northern and southern gradients. Plant material was collected from Gaziantep and Nevsehir provinces in Turkey and from wild populations in Lithuania. A complex of nine hydroxycinnamic acids and eleven flavonoids was identified and quantified in the methanolic extracts of inflorescences, leaves, and stems using the HPLC-PDA method. Caffeoylquinic acids predominated in leaves, while inflorescences tended to prevail in flavonoids. The PCA score plot model represented the quantitative distribution pattern of phenolic compounds along a geographical gradient of populations. The content of phenolic compounds in plant materials from northern latitudes was more than twice that of plants from southern latitudes. A significant correlation of individual phenolic compounds with latitude/longitude corresponded to their differences between two countries. Differences in accumulation of caffeoylquinic acids and flavonoids revealed several intraspecific groups within A. millefolium. Our findings suggest that spatial geographical data on the distribution of phenolic compounds in A. millefolium populations could be used as a tool to find potential collection sites for high-quality raw materials.

Distribution of Phenolic Compounds and Antioxidant Activity in Plant Parts and Populations of Seven Underutilized Wild Achillea Species.

Evaluation of phytochemical composition of underutilized Achillea species provides the primary selection of germplasms with the desired quality of raw material for their further applications. The aim of the study was to evaluate the comprehensive distribution patterns of phenolic compounds in seven wild Achillea spp. and their plant parts, and to assess their antioxidant activity. Plant material was collected from different sites in Turkey. A complex of hydroxycinnamic acids, flavonols and flavones was identified and quantified in methanolic extracts using HPLC-PDA method. Antioxidant activity was assessed by radical scavenging assay. The results showed that qualitative and qualitative profiles of caffeoylquinic acids and flavonoids were species-specific, explaining the characteristic patterns of their variation in the corresponding species and plant parts. The highest total amount of caffeoylquinic acids was detected in A. setacea. A. arabica exposed the highest accumulation of mono-caffeoylquinic acids and flavonoids with the greatest levels of quercetin and luteolin derivatives and the flavonol santin. Santin was detected in all plant parts of A. cappadocica, A. setacea, A. santolinoides subsp. wilhelmsii, and A. arabica. A notable antiradical capacity was confirmed in A. arabica, A. setacea and A. cappadocica plant extracts. The leaves of all studied species were found to have priority over inflorescences and stems in terms of radical scavenging activity. The new data complemented the information that may be relevant for the continuation of chemophenetic studies in the heterogeneous genus Achillea.

Secondary metabolites of seven Hypericum species growing in Turkey.

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.

Morphogenetic changes in essential oil composition of Hypericum perforatum during the course of ontogenesis.

CONTEXT: In the past few years, an increasing interest in the volatile secondary metabolites of Hypericum perforatum L. (Guttiferae) has been arising. OBJECTIVE: The present study is a contribution to better understand the relationship between the morphological variations and volatile composition during the phenological cycle. MATERIALS AND METHODS: Leaves at the stages of vegetative, floral budding, flowering and green capsule, buds, full opened flowers and green capsules were assayed for essential oil (EO) components by gas chromatography-flame ionization detector (GC-FID) and GC-mass spectrometry (MS). RESULTS: Significant amounts of sesquiterpenes (oxygenated 26-50% and hydrocarbons 20-40%) and oxygenated hydrocarbons (13-38%) characterized the all analyzed samples showing peculiar fluctuations during the seven phenological stages. Although monoterpenes were present in much lower amounts (monoterpene hydrocarbons 0.4-6%; oxygenated monoterpenes 0.8-6%) they were considered also important discrimination for several stages. The green capsules and the full opened flowers collected at flowering stage were clearly distinguished in terms of EO compositions from the other samples. DISCUSSION: For the first time, the EO composition of Turkish wild Hypericum perforatum was monitored by the hydrodistillation of different plant organs collected at different seven stages in order to point out the modification of target volatiles related to each phenological step. CONCLUSIONS: Based on the EO composition monitored during these seven morphological stages by GC-MS, principal component analysis and cluster analysis, significant metabolite modifications were observed during the phenological cycle which involved the levels of specific volatile target compounds belonging to the chemical classes of hydrocarbons, monoterpenes and sesquiterpenes.

Essential oil composition and variability of Hypericum perforatum from wild populations of northern Turkey.

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.