Gregoris Iatrou

Distribution of the endemic Balkan flora on serpentine I. – obligate serpentine endemics

Abstract.Serpentine (ophiolithic) substrate covers large areas in the Balkans, more so than in any other part of Europe. These areas extend from north to south mainly in the mountainous central regions and represent specialized habitats for basiphilous-calcifugal plants. Biodiversity in the area is high, with a great number of interesting local and regional endemics. The high number of endemics indicates the importance of serpentine habitats as centres for floristic differentiation and speciation. The number of Balkan endemics growing on serpentine is c. 335 taxa (species and subspecies) of which 123 are obligate. Their distribution is presented in 50 × 50 km UTM squares as adopted in the Atlas Florae Europaeae project coordinated at Helsinki. The richest (in number of taxa) squares are situated in NW Greece (Epirus), the island of Evvia, N Albania together with SW Serbia, and N Greece (Vourinos). They indicate important centres of plant diversity in the Balkans, areas to be noted for conservation strategy. Features responsible for the distribution and abundance of these obligate serpentine endemics include: 1) edaphic isolation in relation to type of bedrock (lime, dolomite, marble, schist, etc.), 2) mountain island isolation (Smolikas, Vourinos, Ostrovica, etc.), 3) island isolation (Evvia) and 4) continuous long-term isolation without interruption or disturbance of speciation.

Species diversity, endemism and conservation of the family Caryophyllaceae in Greece

The family Caryophyllaceae includes world-wide 86 genera and approximately 2100 species. Greece is one of its most important centres of diversity and endemism. A total of 428 Caryophyllaceae taxa are distributed in Greece, 161 of them being endemic to the Greek political territory. The endemic element represents approximately 5% of the global diversity of the family at the species level. The aim of this paper is to discuss the distribution patterns of the Greek endemic Caryophyllaceae, as well as those with a limited distribution range to the neighbouring areas of the Balkans and Anatolia, on the basis of the phytogeographical regions of Greece in order to identify the important regions for their conservation. The majority of the Greek endemic Caryophyllaceae (64.6%) are distributed in only one single phytogeographical region, or even a smaller area indicating the extremely restricted distribution ranges of the endemic plants in Greece. Actually 83 Greek endemic Caryophyllaceae can be grouped on cytotaxonomic criteria. Most of them belong to the category of schizoendemics (91.6%), indicating that the endemism of Caryophyllaceae in Greece has mainly originated in an active way. Cluster analysis has been used to classify the phytogeographical regions according to their floristic similarities. Two iterative complementarity methods were used to evaluate the importance of each phytogeographical region in the conservation of the endemic Caryophyllaceae in Greece. Peloponnisos, Kriti-Karpathos and Sterea Ellas are the most important phytogeographical regions in this respect, followed by North Central and North East. When adding the Balkan-Aegean-Anatolian endemics to the analysis, Peloponnisos, North Central, Kriti-Karpathos, North East and Eastern Aegean result as the most important areas. In every case, an elevated number of sites are required for the conservation of Caryophyllaceae in Greece, reflecting the great dissimilarities in the floristic composition of the various phytogeographical regions. The results provided by the different methods are compared. A catalogue of the Greek endemic Caryophyllaceae is appended.

Contribution to the study of the Greek flora: Flora and vegetation of the Enousses (Oinousses) islands (E. Aegean area)

Summary Enousses is an islets group situated eastwards of Chios island (E. Aegean, Greece), which remained quite unexplored floristically. Based on our herborizations, 270 taxa belonging to 51 families and 204 genera of spermatophytes are listed for the flora of this area. The flora of the area is analysed and the plant species recognized are classified into 9 chorological groups and 5 life form types. The results of this analysis confirm the Mediterranean character of the flora since the Mediterranean elements and the therophytes are predominant in the area. The vegetation of all islets is characterized by the dominance of phryganic communities, and the three “vegetation zones” distinguished (littoral, sublittoral and interior ones) are described. Geological history, geography, microecological differences, random events and human activities seem to be the most important factors related to the diversity of the flora and vegetation observed in our area. Special attention has been given to human interference, since in the bigger islets of the group -which are used for agriculture, grazing etc. - high percentages of Therophytes and Leguminous species have been observed (indexes of disturbance). On the contrary, in the smaller ones, which are not affected by human activities (i.e. Vatopoula), these indexes show deviate values. For this reason, the importance of the small islets ecosystems in floristic and ecological studies in the Aegean area is pointed out.

Floristic and phytosociological investigation of the island Antikythera and nearby islets (SW Aegean, Greece)

Abstract Tzanoudakis, D., Panitsa, M., Trigas, P. & Iatrou, G.: Floristic and phytosociological investigation of the island Antikythera and nearby islets (SW Aegean area, Greece). — Willdenowia 36 (Special Issue): 285–301. — ISSN 0511-9618;

Differential antioxidant effects of consuming tea from Sideritis clandestina subsp. peloponnesiaca on cerebral regions of adult mice.

Oxidative stress is involved in the pathophysiology of neurodegenerative diseases and aging. Many species of the genus Sideritis (mountain tea) are widely consumed in the Mediterranean region as herbal tea. This study evaluated the effect of supplementation of mice with herbal tea from Sideritis clandestina subsp. peloponnesiaca on the antioxidant status of different brain regions. To select the most bioactive herbal tea, the polyphenolic content (Folin-Ciocalteu method) and the antioxidant properties (ferric reducing antioxidant power [FRAP] and 2,2-diphenyl-1-picrylhydrazyl assays) of several taxa and different populations of the S. clandestina infusions were measured in vitro. Male adult mice had ad libitum access to water (control) or the herbal tea (4% w/v) for 6 weeks. At the end of the treatment period we assessed the total antioxidant power (FRAP assay) and the levels of malondialdehyde (indicator of lipid peroxidation) and reduced glutathione in the cerebral cortex, cerebellum, and midbrain. These biochemical measures have also been determined in liver samples used as a comparative reference peripheral tissue. Consumption of 4% herbal tea increased the total antioxidant power of the midbrain by 72% (P<.05); a significant (P<.05) decrease in malondialdehyde levels and increase in reduced glutathione content of the cerebellum (78% and 27%, respectively) and midbrain (59% and 32%, respectively) were also observed. These findings indicate that mountain tea consumption enhances the antioxidant defense of the adult rodent brain in a region-specific manner.

The local endemic flora of Evvia (W Aegean, Greece)

Abstract Trigas, P. & Iatrou, G.: The local endemic flora of Evvia (W Aegean, Greece).— Willdenowia 36 (Speciar Issue): 257–270. — ISSN 0511-9618;

Vascular plants of Greece: An annotated checklist. Supplement

Abstract: Supplementary information on taxonomy, nomenclature, distribution within Greece, total range, life form and ecological traits of vascular plants known to occur in Greece is presented and the revised data are quantitatively analysed. Floristic discrepancies between Vascular plants of Greece: An annotated checklist (Dimopoulos & al. 2013) and relevant influential datasets (Flora europaea, Med-Checklist, Euro+Med PlantBase, etc.) are explained and clarified. An additional quantity of synonyms and misapplied names used in previous Greek floristic literature is presented. Taxonomic and floristic novelties published after 31 October 2013 are not considered. Citation: Dimopoulos P., Raus Th., Bergmeier E., Constantinidis Th., Iatrou G., Kokkini S., Strid A. & Tzanoudakis D. 2016: Vascular plants of Greece: An annotated checklist. Supplement. — Willdenowia 46: 301–347. doi: http://dx.doi.org/10.3372/wi.46.46303 Version of record first published online on 26 October 2016 ahead of inclusion in December 2016 issue.

Quantitation of Crocins and Picrocrocin in Saffron by HPLC: Application to Quality Control and Phytochemical Differentiation from Other Crocus Taxa

A chromatographic method was developed and fully validated for the determination of the major saffron constituents, i.e., picrocrocin and five major crocins. Dried samples (styles of Crocus sativus and other Crocus taxa) were extracted with MeOH : water (1 : 1, v/v), and chromatographic separation of the analytes was achieved by reversed-phase chromatography using a gradient elution. Full validation was performed using spiked samples with analytes, which were isolated, purified, and characterized by MS due to a lack of commercial standards. The method showed a good fit (r2 > 0.999) for all analytes with limit of quantitation values in the range of 1-15 µg/mL, and demonstrated adequate intra- and inter-precision (< 15 % RSD) and accuracy (< 7 % RE). The method was applied to the analysis of various commercial saffron samples and of indigenous Crocus taxa and allowed for the first time the absolute quantitation of several Crocus components.

Polygala rausiana (Polygalaceae), a new species from the northern Peloponnese, Greece

Abstract Raabe U., Tan K., Iatroú G., Vold G. & Parolly G.: Polygala rausiana (Polygalaceae), a new species from the northern Peloponnese, Greece. — Willdenowia 39: 69–75. — Online ISSN 1868-6397;

Effect of acidic and enzymatic pretreatment on the analysis of mountain tea (Sideritis spp.) volatiles via distillation and ultrasound-assisted extraction

A number of beneficial medicinal properties are attributed to the extract and essential oil of the aerial parts of Sideritis species (Lamiaceae). Hydrodistillation of the aerial parts of wild Sideritis clandestina ssp. peloponnesiaca (an endemic taxon in northern Peloponnesus, Greece) gave a low essential oil yield (<0.12%); about 65 components, mainly α-pinene, β-caryophyllene, β-pinene, globulol, caryophyllene oxide, were identified via GC-MS. Internal and external standards were used for quantification. For miniaturization of the procedure, we studied side-by-side maceration (MAC) and ultrasound-assisted extraction (UAE) methods, as well as the effect of preincubation in acidic medium (pH 4.8) for 75min at 37°C with or without a mixture of cellulase, hemicellulase and pectinase. Maceration and UAE provide consistent chemoprofiling of the main volatile compounds (about 20); UAE has lower demands on time, solvent, plant material (3g) and results in higher yields. Pretreatment with enzymes can increase the respective yields of hydrodistillation and UAE, but this effect is definitely attributed to the concurrent acidic pretreatment. In conclusion, incubation of plant material prior to hydrodistillation or UAE in citrate buffer, pH 4.8, significantly enhances the overall yield and number of components obtained and is recommended for the analysis of Sideritis volatiles. The acidic pre-treatment method was also successfully applied to analysis of cultivated Sideritis raeseri Boiss. & Heldr. in Boiss. ssp. raeseri; α-pinene, α- and γ-terpinene and β-thujene were predominant albeit in different percentages in flowers and leaves.