Publications

The purpose of this work was to find a simple, cheap, and suitable method, among the most widely employed, able to guarantee a proper determination and quantification of the phenolic content of extra virgin olive oils (EVOOs), in order to satisfy the requirements of the specific health claim (EU Reg. 432/2012). Total phenolic content by Folin–Ciocalteu (FC) was used and compared versus phenolic profile by HPLC‐UV, considering this latter as the most sensitive and specific method for evaluating the phenolic content. Both protocols were performed before and after an acid hydrolysis of the polar phenolic fraction that involves a break of the bound forms of hydroxytyrosol (HTyr) and tyrosol (Tyr), with a simplification of the phenolic profile, and quantification of their total free forms. Results of the phenolic compounds of twelve EVOOs, determined by the different analytical approaches, were statistically compared by means of two‐tailed paired t ‐tests: data obtained by the FC assay (expressed as HTyr) before and/or after acid hydrolysis were statistically comparable with results obtained by acid hydrolysis‐HPLC (as sum of HTyr and Tyr). Practical applications: The promising results obtained in this study show that the simple and cheap colorimetric assay based on the use of the FC reagent, commonly used for the evaluation of phenolic compounds in hydro‐alcoholic extracts of EVOO, can be also efficiently applied, without acid hydrolysis of extracts and HPLC analysis, to verify the compliance to the polyphenols health claim introduced by EU Reg. 432/2012. In fact, in order to preserve the positive image of EVOO due to its healthy properties, it is necessary i) to share an analytical protocol to determine the amount of hydroxytyrosol and its derivatives having a demonstrated effect of protection of blood lipids from oxidative stress ii) to check by this protocol if EVOOs satisfy the EU requirement for including the specific health claim on the oil label. The simple and cheap Folin–Ciocalteu colorimetric assay, commonly used for the evaluation of phenolic compounds in hydro‐alcoholic extracts of EVOO, can also be efficiently applied to verify the compliance to the health claim introduced by EU Reg. 432/2012.

Abstract Inferring changes in effective population size (Ne) in the recent past is of special interest for conservation of endangered species and for human history research. Current methods for estimating the very recent historical Ne are unable to detect complex demographic trajectories involving multiple episodes of bottlenecks, drops, and expansions. We develop a theoretical and computational framework to infer the demographic history of a population within the past 100 generations from the observed spectrum of linkage disequilibrium (LD) of pairs of loci over a wide range of recombination rates in a sample of contemporary individuals. The cumulative contributions of all of the previous generations to the observed LD are included in our model, and a genetic algorithm is used to search for the sequence of historical Ne values that best explains the observed LD spectrum. The method can be applied from large samples to samples of fewer than ten individuals using a variety of genotyping and DNA sequencing data: haploid, diploid with phased or unphased genotypes and pseudohaploid data from low-coverage sequencing. The method was tested by computer simulation for sensitivity to genotyping errors, temporal heterogeneity of samples, population admixture, and structural division into subpopulations, showing high tolerance to deviations from the assumptions of the model. Computer simulations also show that the proposed method outperforms other leading approaches when the inference concerns recent timeframes. Analysis of data from a variety of human and animal populations gave results in agreement with previous estimations by other methods or with records of historical events.

Middle East respiratory syndrome coronavirus (MERS-CoV) is a highly infectious zoonotic virus first reported into the human population in September 2012 on the Arabian Peninsula. The virus causes severe and often lethal respiratory illness in humans with an unusually high fatality rate. The N-terminal domain (NTD) of receptor-binding S1 subunit of coronavirus spike (S) proteins can recognize a variety of host protein and mediates entry into human host cells. Blocking the entry by targeting the S1-NTD of the virus can facilitate the development of effective antiviral drug candidates against the pathogen. Therefore, the study has been designed to identify effective antiviral drug candidates against the MERS-CoV by targeting S1-NTD. Initially, a structure-based pharmacophore model (SBPM) to the active site (AS) cavity of the S1-NTD has been generated, followed by pharmacophore-based virtual screening of 11,295 natural compounds. Hits generated through the pharmacophore-based virtual screening have re-ranked by molecular docking and further evaluated through the ADMET properties. The compounds with the best ADME and toxicity properties have been retrieved, and a quantum mechanical (QM) based density-functional theory (DFT) has been performed to optimize the geometry of the selected compounds. Three optimized natural compounds, namely Taiwanhomoflavone B (Amb23604132), 2,3-Dihydrohinokiflavone (Amb23604659), and Sophoricoside (Amb1153724), have exhibited substantial docking energy >−9.00 kcal/mol, where analysis of frontier molecular orbital (FMO) theory found the low chemical reactivity correspondence to the bioactivity of the compounds. Molecular dynamics (MD) simulation confirmed the stability of the selected natural compound to the binding site of the protein. Additionally, molecular mechanics generalized born surface area (MM/GBSA) predicted the good value of binding free energies (ΔG bind) of the compounds to the desired protein. Convincingly, all the results support the potentiality of the selected compounds as natural antiviral candidates against the MERS-CoV S1-NTD.

The emergence of several novel SARS-CoV-2 variants regarded as variants of concern (VOCs) has exacerbated pathogenic and immunologic prominences, as well as reduced diagnostic sensitivity due to phenotype modification-capable mutations. Furthermore, latent and more virulent strains that have arisen as a result of unique mutations with increased evolutionary potential represent a threat to vaccine effectiveness in terms of incoming and existing variants. As a result, resisting natural immunity, which leads to higher reinfection rates, and avoiding vaccination-induced immunization, which leads to a lack of vaccine effectiveness, has become a crucial problem for public health around the world. This study attempts to review the genomic variation and pandemic impact of emerging variations of concern based on clinical characteristics management and immunization effectiveness. The goal of this study is to gain a better understanding of the link between genome level polymorphism, clinical symptom manifestation, and current vaccination in the instance of VOCs.

In the marine gastropod Littorina saxatilis differences in relative shell apertural form between two ecotypes from NW Spain have been associated with an environmental cline related to the degree of wave exposure. Such differences have been claimed to have a strong genetic basis, with little influence of phenotypic plasticity. However, dietary changes are expected to affect the growth rate and, potentially, the shell shape, and could thus challenge the adaptive interpretation of the polymorphism. To address this issue we performed a laboratory experiment to grow one of these ecotypes under different food treatments with the aim of testing differences in shell growth. We then investigated the correlation of shell size and shape to quantify the impact of growth on shell aperture. Our results reveal significant dietary effects, an increase in growth rate leading to larger relative apertural size. However, this change occurs in the opposite direction to that expected from the differences between the two ecotypes in nature. This is in line with the low contribution of phenotypic plasticity to the polymorphism observed in previous studies.