Re-discovering Prunus fruit varieties as antiangiogenic agents by metabolomic and bioinformatic approach

In this work, a comparative chemical-biological study of nine plum varieties (Prunus domestica L. and Prunus salicina Lindl.) with two commercial ones was carried out to improve their cultivation and use in the agri-food chain. The chemical quali-quantitative fingerprint by HR-Orbitrap/ESI-MS showed similar profiles, being 'Rossa Casa Velasco' the richest in phenols and anthocyanins. All the extracts were investigated for their in vitro antioxidant as well as antiangiogenic activity by two in vivo models, chick chorioallantoic membrane and zebrafish embryos. Among investigated varieties 'Scarrafona', 'Rusticano', 'Marisa', 'Rossa Casa Velasco', 'Verdone', and 'Sangue di Drago' showed the best antiangiogenic activities (30-50 % inhibition). Finally, the chemical/biological datasets processed with a bioinformatic approach revealed that a large group of flavonoids, procyanidins, and anthocyanins significantly correlated with all the three antioxidant tests (DPPH, FRAP, and ABTS), while quinic acid and icariside F2 resulted positively correlated with CAM at both 100 and 200 μg/egg.

Molecular and Evolutionary Characterization of Pollen S Determinant (SFB Alleles) in Four Diploid and Hexaploid Plum Species (Prunus spp.)

In more than 60 families of angiosperms, the self- and cross-fertilization is avoided through a complex widespread genetic system called self-incompatibility (SI). One of the major puzzling issues concerning the SI is the evolution of this system in species with complex polyploid genomes. Among plums, one of the first fruits species to attract human interest, polyploid species represent enormous genetic potential, which can be exploited in breeding programs. However, molecular studies in these species are very scarce due to the complexity of their genome. In order to study the SFB gene [the male component of gametophytic self-incompatibility system (GSI)] in plum species, 36 plum accessions belonging to diploid and hexaploid species were used. A total of 19 different alleles were identified; 1 of them was revealed after analyzing sequences. Peptide sequence analysis allowed identifying the five domains features of the SFB gene. Polymorphism analysis showed a subtle difference between domesticated and open pollinated Tunisian accessions and suggested a probable influence of the ploidy level. Divergence analysis between studied sequences showed that a new specificity may appear after 5.3% of divergence at synonymous sites between pairs of sequences in Prunus insititia, 6% in Prunus cerasifera, 8% and 9% in Prunus domestica and Prunus salicina respectively. Furthermore, sites under positive selection, the ones more likely to be responsible for specificity determination, were identified. A positive and significant Pearson correlation was found between the divergence between sequences, divergence time, fixed substitutions (MK test), and PSS number. These results supported the model assuming that functionally distinct proteins have arisen not as a result of chance fixation of neutral variants, but rather as a result of positive Darwinian selection. Further, the role that plays recombination can not be ruled out, since a rate of 0.08 recombination event per polymorphic sites was identified.

Data on Swiss fruit and wine growers' management strategies against D. suzukii, risk preference and perception

The survey data presented in this article provides information on risk management strategies in response to the invasive pest Drosophila suzukii (spotted wing drosophila) collected among Swiss fruit and wine growers. The survey covered grape, plum, berry and cherry growers and the years 2016, 2017 and 2018. Strategies to prevent or control Drosophila suzukii were collected at the variety level and information on perceived infestation levels as well as harvest losses was collected. In total, nine surveys were conducted, creating a unique panel dataset. Additionally, data was collected with regard to fruit growers’ characteristics (e.g. age, gender) and farm characteristics (e.g. farm size, farm-level workforce, succession, insurance use). Risk preferences were elicited via a self-assessment of risk preferences and (for selected surveys) using a multiple price list. Additionally, (for selected surveys) locus of control and self-efficacy were evaluated via self-assessment questions.

Combination of Simple Sequence Repeat, S-Locus Polymorphism and Phenotypic Data for Identification of Tunisian Plum Species (Prunus spp.)

Plums (Prunus spp.) are among the first fruit tree species that attracted human interest. Artificial crosses between wild and domesticated species of plums are still paving the way for creation of new phenotypic variability. In Tunisia, despite a considerable varietal richness of plum as well as a high economic value, the plum sector is experiencing a significant regression. The main reason of this regression is the absence of a national program of plum conservation. Hence, this work was aimed to phenotypically and genetically characterize 23 Tunisian plum accessions to preserve this patrimony. Closely related Prunus species from the same subgenus may be differing at two characteristics: ploidy level and phenotypic traits. In this study, single sequence repeat (SSR) markers allowed distinguishing between eighteen diploid accessions and five polyploid accessions, but SSR data alone precluded unambiguous ploidy estimation due to homozygosity. In contrast, S-allele markers were useful to identify the ploidy level between polyploid species, but they did not distinguish species with the same ploidy level. Seven out of 12 phenotypic traits were shown to be discriminant traits for plum species identification. Molecular and phenotypic traits were significantly correlated and revealed a powerful tool to draw taxonomic and genotypic keys. The results obtained in this work are of great importance for local Tunisian plum germplasm management.

Industrial prune processing and its effect on pesticide residue concentrations

The aim of this study was to determine the insecticide residue processing factor (PF) from plums to prunes and the effect of the industrial processing of prunes residue concentrations. Our results show an increase of insecticide concentrations during plum dehydration that is explained by fruit water loss; however, the normalized insecticide residue concentration, based on plum dry weights to compensate dehydration, was reduced. The water washing and tenderizing of prunes produced insecticide residue reductions of 22.9 ± 4.5% and 21.9 ± 4.2%, respectively. PF were: 1.157, 1.872, 1.316, 0.192, 2.198, 0.775 and 0.156 for buprofezin, l-cyhalothrin, spirodiclofen, indoxacarb, acetamiprid, imidacloprid and emamectin benzoate, respectively, being directly related to water solubility, aqueous hydrolysis and degradation point and inversely related to molecular mass and melting point. In plums for the dehydrated agroindustry the final product is prunes, therefore, it is crucial to consider the PF to determine the specific preharvest interval for this important agroindustry.

Pectic polysaccharides of the fresh plum Prunus domestica L. isolated with a simulated gastric fluid and their anti-inflammatory and antioxidant activities

A pectic polysaccharide, designated as PD, was extracted from fresh plums (Prunus domestica L.) with a simulated gastric fluid. Galacturonan, which was partially substituted with methyl and O-acetyl ester groups, and rhamnogalacturonan were the main constituents of the linear regions of the sugar chains of PD. The ramified region contained mainly 1,4-linked β-d-galactopyranose residues and, to a lesser extent, 1,5-linked α-l-arabinofuranose residues. The separation of PD, by DEAE-cellulose column chromatography, yielded two pectic fractions: PD-1 and PD-2, eluted with 0.1 and 0.2 M NaCl, respectively. Enzymatic digestion of PD with 1,4-α-d-polygalacturonase yielded the fraction PD-E. The parent pectin PD and the PD-1 fraction were found to diminish the adhesion of peritoneal leukocytes at the concentrations of 0.05-1.0mg/ml. However, the PD-E fraction failed to have an effect on cell adhesion at the concentrations of 0.05-0.1mg/ml. PD, PD-1 and PD-E were found to inhibit the production of superoxide anion radicals by reducing xanthine oxidase activity by 38%, 97% and 47%, respectively. Therefore, the PD-1 fraction appeared to be an active fragment of pectic macromolecule isolated from fresh plum with a simulated gastric fluid.