Eirini Sarrou

Volatile Constituents and Antioxidant Activity of Peel, Flowers and Leaf Oils of Citrus aurantium L. Growing in Greece

The volatile constituents of the essential oils of the peel, flower (neroli) and leaves (petitgrain) of bitter orange (Citrus aurantium L.) growing in Greece were studied by GC-MS. The analytical procedures enabled the quantitative determination of 31 components. More specifically, the components of the essential oils identified were: twelve in the peel, twenty-six in the flowers, and twenty and sixteen in old and young leaves, respectively. The major constituents of the different parts of Citrus aurantium L. essential oils were: β-pinene (0.62%–19.08%), limonene (0.53%–94.67%), trans-β-ocimene (3.11%–6.06%), linalool (0.76%–58.21%), and α-terpineol (0.13%–12.89%). The DPPH test demonstrated that the essential oils in the old leaves had the maximum antioxidant activity, followed by the flowers, young leaves and the peel in that order. This study updates the data in the literature on the essential oils of bitter orange, and provides information on the composition of the oils for a further evaluation of this product.

Effect of melatonin, salicylic acid and gibberellic acid on leaf essential oil and other secondary metabolites of bitter orange young seedlings

An investigation was carried out in order to estimate the biochemical changes occurring in bitter orange (Citrus aurantium L.) leaves in response to melatonin (MEL), gibberellic acid (GA) and salicylic acid (SA) treatments. We examined the effect of MEL, GA and SA on the essential oil (EO), the total phenolic (TPC) and total flavonoid content (TFC), and the antioxidant activity of bitter orange leaves from 1-year-old plants. 15 μMMEL, 1 mMSA and 1.44 mMGA increased the total leaf phenolic and flavonoid content and enhanced FRAP and DPPH activity of leaf methanolic extracts. Salicylic acid and GA promoted the leaf essential oil content and affected significantly the concentration of limonene, linalool and linalyl acetate.

Genetic diversity and metabolic profile of Salvia officinalis populations: implications for advanced breeding strategies

AbstractMain conclusionAs a result of this work, we were able to characterize seven indigenous to GreeceSalvia officinalispopulations using genetic and metabolomic tools. These tools can be used to select the most promising genotypes, capable to design future breeding programs for high valuable varieties. An initial investigation was carried out to compare the genetic and metabolic diversity in S. officinalis grown in Greece and to discern the relationship between the two sets of data. Analysis of inter-simple sequence repeats (ISSR) revealed significant genetic differences among seven sage populations, which were grouped into three main clusters according to an UPGMA ISSR data-based dendrogram and Principle Coordinate Analysis. 80 loci were scored of which up to 90% were polymorphic at species level. According to the composition of their essential oil, the populations were classified into two chemotypes: 1.8 cineole/α-thujone and α-thujone/1.8 cineole. Additionally, a targeted ultra performance liquid chromatography (UPLC–MS/MS) method was used to qualify and quantify phenolic compounds in methanolic extracts of the seven sage genotypes according to which they were districted in six clusters among the sage populations. The main compounds characterizing the seven genotypes were rosmarinic acid and carnosol, followed by apigenin-7-O-glucoside (Ap7glc), and luteolin-7-O-glucoside (Lu7glc). The correlation between matrices obtained from ISSR data and metabolic profiles was non-significant. However, based on the differences in metabolic fingerprint, we aimed to define populations using as main selection criteria the high polyphenol content and desired essential oil composition, using state to the art analytical tools for the identification of parent lines for breeding programs.

Conventional breeding of Greek oregano (Origanum vulgare ssp. hirtum) and development of improved cultivars for yield potential and essential oil quality

This study is an attempt to describe a conventional breeding program on Greek oregano (Origanum vulgare ssp. hirtum). First of all, a descriptor list including the most significant morphological traits was developed for the starting genetic material. The program aimed to select the elite self-plants obtained from the initial population originated from Samothraki Island, in purpose to generate the ideotype of a new cultivar, characterized by desirable agronomical traits and qualitative properties. Therefore, a pedigree intraselection method, based on widely spaced single-plant performance through honeycomb arrangement, was applied. The existing genetic/phenotypic variability of plants and families produced after selection was evaluated for plant’s growth and biomass density, type of stems and inflorescences and their components of yield potential. In addition, the effect of the mode of pollination on plants’ performance from two types of families obtained from self (SP) and open pollination (OP) was assessed. The evaluation for the components of yield potential, the composition of essential oil and carvacrol content, was detected in selected self plants, revealing genotypes with high yield potential. The target of this breeding program was the selection for high essential oil and carvacrol content and stabilization of valuable herbage components. The main selection criteria; high carvacrol and essential oil content, dry weight of leaves and flowers, ratio of leaves and flowers per stem, were subjected to statistical analysis using analytic hierarchy process, and plants were ranking according to their performance. The end-scope of this research was to recombine or even improve the starting population of local population of Greek oregano, according to mean essential oil content and carvacrol, biomass production and uniformity in desirable yield components using efficient breeding and statistical tools of selection.

Metabolomics assisted fingerprint of Hypericum perforatum chemotypes and assessment of their cytotoxic activity

Hypericum perforatum is known as an important medicinal plant, used for the treatment of several diseases, while its pharmacological properties are attributed to the presence of a wide range of secondary metabolites. Due to the great chemotypic variability of Hypericum species in the nature, and the demand for standardized herbal products, a detailed phytochemical investigation was carried out on different parts (herba, leaf, flowers) from wild collected and cultivated populations, using advanced chromatographic tools. Liquid Chromatographic analysis (LC-MS/MS MRM) revealed significant variability in the secondary metabolites content of the examined methanolic extracts. The most common derivatives belong to 9 groups i.e. benzoic acids, phenylpropanoids, coumarins, flavones, flavonols, flavan-3-ols, anthocyanins, phloroglucinols and naphtodianthrones. The main polyphenolic compounds were catechin, epicatechin, quercetin, quercetin 3-O-rhamnoside, quercetin 3-O-glucoside, neochlorogenic acid, proanthocyanidins (A and B series) and cyanidin-3-O-glucoside. In addition, the content of the characteristic compounds hypericin and hyperforin in herba crude extracts ranged between 0.5 and 1.7 mg/g and 0.6-3.3 mg/g respectively. The cytotoxic activity of the crude extracts was assessed at concentrations ranged between 0.01 and 100 μg/mL, on Caco-2 intestinal cancer cell cultures, and a cytotoxic behavior was shown only at the highest concentration of 100 μg/mL.