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Grapevine is one of the most cultivated fruit crop worldwide with Vitis vinifera being the species with the highest economical importance. Being highly susceptible to fungal pathogens and increasingly affected by environmental factors, it has become an important agricultural research area, where gene expression analysis plays a fundamental role. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) is currently amongst the most powerful techniques to perform gene expression studies. Nevertheless, accurate gene expression quantification strongly relies on appropriate reference gene selection for sample normalization. Concerning V. vinifera, limited information still exists as for which genes are the most suitable to be used as reference under particular experimental conditions. In this work, seven candidate genes were investigated for their stability in grapevine samples referring to four distinct stresses (Erysiphe necator, wounding and UV-C irradiation in leaves and Phaeomoniella chlamydospora colonization in wood). The expression stability was evaluated using geNorm, NormFinder and BestKeeper. In all cases, full agreement was not observed for the three methods. To provide comprehensive rankings integrating the three different programs, for each treatment, a consensus ranking was created using a non-weighted unsupervised rank aggregation method. According to the last, the three most suitable reference genes to be used in grapevine leaves, regardless of the stress, are UBC, VAG and PEP. For the P. chlamydospora treatment, EF1, CYP and UBC were the best scoring genes. Acquaintance of the most suitable reference genes to be used in grapevine samples can contribute for accurate gene expression quantification in forthcoming studies.

The cytotoxicity-guided study of the dichloromethane and ethanol extracts of Thymus mastichina L. using the HCT colon cancer cell line allowed the identification of nine compounds, sakuranetin (1), sterubin (2), oleanolic acid (3), ursolic acid (4), lutein (5), β-sitosterol (6), rosmarinic acid (7), 6hydroxyluteolin-7-O-β-glucopyranoside (8), and 6-hydroxyapigenin-7-O-β-glucopyranoside (9). All compounds were tested for their cytotoxicity against the HCT colon cancer cell line. Compound 4 showed cytotoxicity with GI 50 value of 6.8 µg/mL. A fraction composed of a mixture (1:1) of triterpenoid acids 3 and 4 displayed improved cytotoxicity with a GI 50 of 2.8 g/mL suggesting a synergistic behavior. This is the first report on the chemical constituents of Thymus mastichina L. based on structural assignments by spectroscopic analysis. The presence of these constituents identified by colon cancer cytotoxicity-guided activity indicates that extracts of T. mastichina L. may have a protective effect against colon cancers.

In this review a brief description of the invasive phenomena associated with algae and its consequences on the ecosystem are presented. Three examples of invasive algae of Southern Europe, belonging to Rodophyta, Chlorophyta, and Phaeophyta, were selected, and a brief description of each genus is presented. A full description of their secondary metabolites and biological activity is given and a summary of the biological activity of extracts is also included. In Asparagopsis we encounter mainly halogenated compounds. From Caulerpa, several terpenoids and alkaloids were isolated, while in Sargassum, meroterpenoids prevail.

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The development of new drugs that can be valuable for the evolution of diseases' treatment is a goal for different areas of research, namely natural products chemistry, molecular biology and biochemistry, pharmacology, medicinal chemistry, synthetic organic chemistry and analytical chemistry. Nature is the main source of compounds for pharmaceutical purposes, either by providing the natural organic chemical compounds of interest or as a source of inspiration for the design of new drugs. The known anti-inflammatory and anticancer agents belong to a great diversity of structural skeletons since inflammatory and cancer processes involve many different biological targets. Their origins extend to plants, fungi, bacteria, and marine organisms, besides those produced by semi-synthesis and total synthesis. The tasks of the organic chemist are the screening, the structure assignment, and the semi and total syntheses of active molecules. Herein the screening and assignment of new active structures is addressed, together with other aspects, namely the improvements, both in availability and in effectiveness of action that can be achieved from new derivatives by synthetic or semi-synthetic strategies. Some aspects of drug delivery of anti-inflammatory and anticancer agents are considered. The bibliography presented is far from being exhaustive due to the prodigious number of published works. Instead, the most significant contributions in the scope of this review are described. The active compounds are organised by their biosynthetic origins as terpenoids; macrolides, polyketides and ansamycins; phenolics; alkaloids; peptides; glycoconjugates; other compounds, and food compounds.

A comprehensive review on the chemistry of Spongia sp. is here presented, together with the biological activity of the isolated compounds. The compounds are grouped in sesquiterpene quinones, diterpenes, C21 and other linear furanoterpenes, sesterterpenes, sterols (including secosterols), macrolides and miscellaneous compounds. Among other reports we include studies on the intraspecific diversity of a Mediterranean species, compounds isolated from associated sponge and nudibranch and compounds isolated from S. zimocca and the red seaweed Laurentia microcladia. Under biological activity a table of the reported biological activities of the various compounds and the biological screening of extracts are described. The present review covers the literature from 1971 to 2015.

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