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The seeds of Paeonia clusii Stern subsp. clusii and Paeonia mascula (L.) Mill. subsp. mascula growing wild in Greece, though not previously investigated, has been studied as a source of bioactive stilbenoids and other phenolics. Their methanol extracts were analyzed using ultra high-performance liquid chromatography—high-resolution mass spectrometry (UHPLC-HRMS), and among the identified metabolites (62), 19 paeoniflorin's derivatives, 17 flavonoids and 12 stilbenes were detected. Moreover, through classic phytochemical separation procedures, twelve among them were isolated and fully spectrally determined as trans-resveratrol, trans-resveratrol-4′-O-β-D-glucopyranoside, cis-resveratrol-4′-O-β-D-glucopyranoside, trans-gnetin-H, trans-ε-viniferin, luteolin, luteolin-3′-O-β-D-glucopyranoside, luteolin-3′,4′-di-O-β-D-glucopyranoside, apigenin, hispidulin, paeoniflorin and benzoyl-paeoniflorin. All seed extracts were measured for their total phenolic content (TPC), appearing as a rich source (116.04 and 103.63 mg GAE/g extract, respectively), followed by free radical (DPPH) scavenging capacity (75.24% and 91.54% inhibition at the concentration of 200 μg/mL). The evaluation of tyrosinase inhibition for both extracts (61% and 70%, respectively) confirmed the potential for their future application in skin health care, comparable with other paeonies of Chinese origin, which are well-known as skin whitening and anti-aging promoters. [ABSTRACT FROM AUTHOR]

In the last decades, Primula veris subsp. veris (roots and flowers) has been over harvested through legal and illegal ways in Greece, due to its extremely high commercial demand, as it is used in industry because of its well-known therapeutic properties. As ex situ cultures of the plant have been already developed, in the current comparative study, the herbal teas (infusions) from both flowers of cowslip growing wild in the Prespa Lake Park (NW Greece), and from ex situ propagated and cultivated plant material, have been investigated, with the ultimate goal of assessing them qualitatively. Furthermore, through classic phytochemical studies, the ten most abundant metabolites, belonging to the chemical categories of flavonol-glycosides and methoxy flavones, have been identified and structurally determined. The chemical profile of both infusions has been further analyzed through UHPLC-HRMS, showing that they show only light differences. The total phenolic content (TPC) of both studied samples (wild and ex situ cultivation), was determined by the Folin–Ciocalteau method, followed by an antioxidant activity assay though DPPH where, in both cases, wild plants exerted higher phenolic load and stronger antioxidative properties. According to the reported results, it could be proposed that the ex situ cultivated plant material could facilitate the mass production of plants and the sustainable cultivation of cowslip in the Greek mountains. [ABSTRACT FROM AUTHOR]

Chemical composition of propolis depends on the plant source and thus on the geographic and climatic characteristics of the site of collection. The aim of this study was to investigate the chemical profile of Greek and Chinese propolis extracts from different regions and suggest similarities and differences between them. Untargeted ultrahigh-performance liquid chromatography coupled to hybrid quadrupole-Orbitrap mass spectrometry (UHPLC-HRMS) method was developed and 22 and 23 propolis samples from Greece and China, respectively, were analyzed. The experimental data led to the observation that there is considerable variability in terms of quality of the distinctive propolis samples. Partial least squares - discriminant analysis (PLS-DA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) models were constructed and allowed the identification of significant features for sample discrimination, adding relevant information for the identification of class-determining metabolites. Chinese samples overexpressed compounds that are characteristic of the poplar type propolis, whereas Greek samples overexpress the latter and the diterpenes characteristic of the Mediterranean propolis type. [ABSTRACT FROM AUTHOR]

The present study describes the peculiar phytochemical characteristics of bergamots cultivated in distinct islands of the Ionian Sea. Ultrahigh-performance liquid chromatography high-resolution mass spectrometry (UHPLC-HRMS) supported by 1 and 2D NMR spectroscopy was used for unambiguous metabolic profiling of albedo, flavedo and juice samples. Profile differences were determined using a multi-analytical clustering approach based on high-performance thin-layer chromatography fingerprints and UHPLC-HRMS data. Finally, a validated HPLC method offering good precision (0.12-0.94%) and accuracy (95.25-103.93%) was proposed for the quantification of the major flavanones. A total of 37 secondary metabolites were characterized belonging to flavonoids, limonoids and coumarins. Their distribution was tissue-dependent and varied significantly from bergamots of other geographical locations. Surprisingly, neoeriocitrin was the major flavanone, reaching 1.69 ± 0.05 g/L in the juice and 5.24 ± 0.12 mg/g in albedo. This is the highest reported amount among Citrus species, rendering Ionian bergamots a promising candidate for novel functional products., (Copyright © 2020 Elsevier Ltd. All rights reserved.)