EVOO or not EVOO? A new precise and simple analytical tool to discriminate extra virgin olive oils

International Olive Oil Council (IOOC) states chemical and organolep- tic parameters to classify the commercial grade of olive oil. Finding tools or analytical procedures able to support the organoleptic evaluation would be helpful to streamline and facilitate the commercial classification. The aim of the present study was to evaluate a new tool and validate a procedure that allows a fast and non-invasive volatile compounds detection system, able to assign each sample to its right trade category. Moreover, we tried to test the capabili- ty of PTR-ToF-MS in grading olive oils according to their fruity intensity levels. A total of 273 olive oil samples collected from Argentina (21), Chile (10), Italy (191), Morocco (17), Tunisia (4) and EU (30) were analyzed and classified through: (1) Panel Test and (2) PTR-ToF-MS analysis. On the whole PTR-ToF-MS data EVOO and Not EVOO as resulted by Panel Test were clustered by PCA in two main groups and correctly classified by PLS-DA model, confirming the high confidence level (95%) in utilizing analytical spectral data for helping Panel Test and able to easy monitoring the quality formation in the oils, by a fast and cheap control from harvest until the store. The eight protonated masses detected as VIP by the model may be linked to negative olfactory notes. Finally, PCA applied on the volatile profile of 122 classified EVOO highlighted a shift of the samples distribution following the trend of the fruity intensity as assessed by the panelists. In conclusion, this trial confirmed the availability of a new, precise and simple analytical tool as the PTR-ToF-MS, which coupled with an appropriate multivariate data analysis, allows to classify EVOO according to their trade category and fruity intensity.

The network of plants volatile organic compounds

Plants emission of Volatile Organic Compounds (VOCs) is involved in a wide class of ecological functions, as VOCs play a crucial role in plants interactions with biotic and abiotic factors. Accordingly, they vary widely across species and underpin differences in ecological strategy. In this paper, VOCs spontaneously emitted by 109 plant species (belonging to 56 different families) have been qualitatively and quantitatively analysed in order to provide an alternative classification of plants species. In particular, by using bipartite networks methodology from Complex Network Theory, and through the application of community detection algorithms, we show that is possible to classify species according to chemical classes such as terpenes and sulfur compounds. Such complex network analysis allows to uncover hidden plants relationships related to their evolutionary and adaptation to the environment story

Morpho-chemical and aroma investigations on autochthonous and highly-prized sweet cherry varieties grown in Tuscany

The morpho-chemical and aromatic characteristics of four sweet cherry cultivated varieties (Prunus avium L.) grown in the area of Lari (Pisa, Central Italy) were evaluated with the aim to investigate their properties, mainly concerning volatile organic compounds (VOCs). Of these, three cultivars (‘Di Giardino’, ‘Di Nello’, and ‘Marchiana’) represent ancient sweet cherries recovered through a private cultivation program (belonging to the group of the so-called ‘Ciliegia di Lari’); their evaluation was compared with the commercial cultivar Ferrovia, highly-prized variety marketed in Italy and abroad. Morpho-chemical analyses highlighted statistical differences among the cultivars under study, mainly on total soluble solids (TSS) and tritatable acidity (TA). Aroma investigation was performed with PTR-ToF-MS (proton transfer reaction - time of flight - mass spectrometer) approach, employed here for the first time in cherry fruits. About 50 VOCs were detected; among them, those belonging to the chemical classes of aldehydes and alcohols were the most represented although with different intensities between samples. Tentative identification of some key VOCs for cherry fruit was also performed and preliminary conclusions on the characterization of ancient and wide spread Italian cultivars were given

A molecular phylogeny of Porcellionidae (Isopoda, Oniscidea) reveals inconsistencies with present taxonomy

Porcellionidae is one of the richest families of Oniscidea globally distributed but we still lack a comprehensive and robust phylogeny of the taxa that are assigned to it. Employing five genetic markers (two mitochondrial and three nuclear) we inferred phylogenetic relationships among the majority of Porcellionidae genera. Phylogenetic analyses conducted via Maximum Likelihood and Bayesian Inference resulted in similar tree topologies. The mtDNA genes cytochrome oxidase I (COI) and 16s rRNA (16s) were used for clade dating using previously published mutation rates. Our results provide evidence against the monophyly of both Porcellionidae and the largest genus of the family Porcellio. These results are compared to previous published work based on morphological evidence. The genera Leptotrichus and Brevurus are not grouped with the rest of Porcellionidae whereas Agnaridae are grouped with part of Porcellionidae. Armadillidium and Schizidium (Armadillidiidae) occupy a basal position on the phylogenetic tree. Even though the African genera Tura and Uramba (distributed in East Africa) are grouped together there is no general geographical pattern in other sub-clades. Additional taxonomic issues that arise in this work such as the assignment of the recently described genus Levantoniscus, arealso discussed. The status of Porcellionidae should be further revised and morphological characters traditionally used in Oniscidea taxonomy should be reconsidered in view of molecular evidence. The origin of the monophyletic clade within Porcellionidae as indicated in the present work is dated back to the Oligocene (~32 mya)

Phylogeography of Supralittoral Rocky Intertidal Ligia Isopods in the Pacific Region from Central California to Central Mexico

Ligia isopods are widely distributed in the Pacific rocky intertidal shores from central California to central Mexico, including the Gulf of California. Yet, their biological characteristics restrict them to complete their life cycles in a very narrow range of the rocky intertidal supralittoral. Herein, we examine phylogeographic patterns of Ligia isopods from 122 localities between central California and central Mexico. We expect to find high levels of allopatric diversity. In addition, we expect the phylogeographic patterns to show signatures of past vicariant events that occurred in this geologically dynamic region.We sequenced two mitochondrial genes (Cytochrome Oxidase I and 16S ribosomal DNA). We conducted Maximum Likelihood and Bayesian phylogenetic analyses. We found many divergent clades that, in general, group according to geography. Some of the most striking features of the Ligia phylogeographic pattern include: (1) deep mid-peninsular phylogeographic breaks on the Pacific and Gulf sides of Baja peninsula; (2) within the Gulf lineages, the northern peninsula is most closely related to the northern mainland, while the southern peninsula is most closely related to the central-southern mainland; and, (3) the southernmost portion of the peninsula (Cape Region) is most closely related to the southernmost portion of mainland.Our results shed light on the phylogenetic relationships of Ligia populations in the study area. This study probably represents the finest-scale phylogeographic examination for any organism to date in this region. Presence of highly divergent lineages suggests multiple Ligia species exist in this region. The phylogeographic patterns of Ligia in the Gulf of California and Baja peninsula are incongruent with a widely accepted vicariant scenario among phylogeographers, but consistent with aspects of alternative geological hypotheses and phylo- and biogeographic patterns of several other taxa. Our findings contribute to the ongoing debate regarding the geological origin of this important biogeographic region