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During last years, skin pitting symptoms on kiwifruit, caused by Cadophora luteo-olivacea, were detected in packaging houses of different geographic areas. In this study, the kiwifruits ripeness stage was considered a possible condition influencing fungal virulence. FT-IR analysis confirmed that unripe kiwifruits are more susceptible to fungal attack. By observations at the Scanning Electron Microscope (SEM), we were able to follow month by month C. luteo-olivacea infection strategy. Once inside kiwifruit, the pathogen can colonize kiwifruit pulp just under the skin starting from the first month but modifying its structural composition only in the third and fourth months. [ABSTRACT FROM AUTHOR]

The most common leguminous plants' diseases are caused by soil-borne pathogens leading to important economic losses worldwide. Strains L1 and L8, belonging to Aureobasidium pullulans species, were tested in vitro and in vivo as biocontrol agents (BCAs) against Rhizoctonia solani (Rs1) (AG-4) and as plant growth promoters (PGPs). The non-volatile metabolites produced by L1 and L8 strains inhibited the pathogen mycelial growth by 87.9% on average, with no significant differences between the two strains. The lower pathogen diametric growth inhibition was displayed by both yeasts' volatile metabolites (VOCs) that significantly reduced the colony growth of R. solani, and similarly to the control, with an average of 10.5%. By in vivo assay, L1 and L8 strains showed the ability to control the pathogen virulence probably through the biofilm formation around the bean and soybean plant roots, as confirmed by scanning electron microscope (SEM) analysis. The spectroscopic analysis highlighted the composition of non-volatile compounds: complex carbohydrates (pullulan), degrading enzymes, siderophores and antifungals (aureobasidins). Moreover, the ability of L1 and L8 strains to stimulate the bean and soybean plant roots, stems, and leaves growth was investigated, showing that these yeasts could have an application not only as BCAs but also as plant growth biostimulator. [ABSTRACT FROM AUTHOR]

Due to climate change, Neofusicoccum parvum is currently emerging as a new pathogen of Rosaceae plant species. This increases the need of gaining knowledge on the pathogenicity of this fungus, particularly on apple cultivars of considerable economic importance. In this study, the virulence and temperature dependence of N. parvum isolates was assayed on 'Gala' and 'Fuji' apple fruit and wood. At 25 °C and 30 °C, 'Gala' fruits showed a higher susceptibility to all fungal strains than 'Fuji', whereas low infection severity was shown at 15 °C and 20 °C on both cultivars. Infrared spectroscopy revealed that 'Fuji' fruit tissues displayed a higher content of phenolic compounds and pectin esterification degree, as factors possibly correlated with fruit susceptibility. When strain virulence was assayed on wood, no significant difference in susceptibility was detected, as also shown by SEM analysis. The virulence of N. parvum was also tested by assaying the activity of lytic enzymes such as cellulase, polygalacturonase, polymethylgalacturonase, and xylanase. [ABSTRACT FROM AUTHOR]

BACKGROUND: Metal ions are implicated in protein aggregation processes of several neurodegenerative pathologies, where the protein deposition occurs, and in the biotechnology field like the food technology where many processes in food manufacturing are based on thermal treatments. OBJECTIVE: The influence of Cu2+ or Zn2+ ions on the thermal aggregation process of Bovine β-lactoglobulin (BLG) and Bovine Serum Albumin (BSA), two protein models, was studied with the aim of delineating the role of these ions in the protein aggregation kinetics and to clarify the related molecular mechanisms. METHODS: The protein structure changes were monitored by Raman spectroscopy, whereas the aggregate growth was followed by Dynamic Light Scattering measurements. RESULTS: Both metal ions are able to favour the BLG aggregation, whereas only Zn2+ ions have a promoter effect on the thermal aggregation of BSA. The reason of this different behaviour is that the BLG aggregation evolution is manly affected by the redistribution of charges, whereas that of BSA by the metal coordination binding which depends on metal. CONCLUSIONS: Raman spectroscopy, combined with dynamic light scattering experiments, was very useful in identifying the role played by Cu2+ and Zn2+ on the aggregation pathways of BLG and BSA. The results provide evidence for the role of histidine residues both in the redistribution of charges and in the two modes of metal binding that take place in BLG- and BSA-containing systems, respectively. [ABSTRACT FROM AUTHOR]

Background and Aims The present study investigated the effectiveness of bovine blood ( BB)-based products, compared with that of the widely used iron ethylenediaminedi-(2-hydroxyphenylacetic) acid ( Fe- EDDHA) synthetic chelate, in iron nutrition of grapevine graft combinations and rootstocks grown under different controlled conditions. Methods and Results In experiments under nutrient solution utilising rhizoboxes and pots, the effect of iron application treatments was evaluated through biometric and chlorophyll index measurements, leaf nutrient concentration and root scanning electron microscopy. Conclusions The bovine blood compounds improved iron nutrition of the grapevine similar to or better than Fe- EDDHA and enhanced root growth. Significance of the Study The experimental evidence indicates that BB-based products represent a sustainable alternative to synthetic chelates as Fe fertilisers. [ABSTRACT FROM AUTHOR]

EAK16 (AEAEAKAKAEAEAKAK) and seven alternating polar/hydrophobic oligopeptides (derived from EAK16 by primary structure modifications) were tested for their resistance to free radical attack, in view of their possible use as biomimetic coatings of biomedical devices; in fact, oxidative radical stress, mainly due to hydroxyl radicals (•OH), is a common physiological condition occurring under acute or chronic inflammatory response. •OH radicals, mimicking an endogenous radical stress, were generated by gamma-radiolysis of water solutions. IR and Raman spectroscopies were used to investigate the damages induced by free radicals on the oligopeptides, in particular on their folding and inter-chain interactions. Some oligopeptides, i.e. EAK16 (pept1), pept3 (obtained by K → O substitution), pept5 (A → Abu substitution), pept7 (insertion at the N-terminus of the RGD sequence), and pept8 (RGD insertion and 'scrambling' of the sequence) were not severely affected by the treatment and retained their prevalent structure (i.e. α-helix for pept8 and β-sheet for the others). The other peptides, i.e. pept2 (obtained by E → D substitution), pept4 (E → D and K → O substitutions) and pept6 (A → Y substitution), showed significant conformational changes (i.e. increase in the α-helix content) upon irradiation. In pept2 and pept4, modifications in hydrophobic and ionic interactions were observed; the latter were mainly ascribed to the decarboxylation of acidic amino acids. In pept6, the main target of the •OH attack was Tyr, as deduced by the strong variations observed in Tyr bands both in IR and Raman spectra. This study may contribute to gain insight into the different biological performances of the EAK16-derived peptides and to identify the most adequate materials usable for bone regeneration. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, the effect of increasing amounts of lysozyme (Lyso) and bovine serum albumin (BSA) on the behaviour of lecithin (DMPC) and cephalin (DMPE) liposomes was investigated by means of Raman and DSC techniques. The results showed that both proteins affected, but in a different way, both lecithin and cephalin liposomes. In the samples with lower Lyso concentrations (up to 2 % w/w), a small decrease on the main transition temperature ( T) was observed, whereas T increased by further addition of Lyso (up to 15.0 % w/w). At the same time, an increase of about 20 % in the Δ H of the transition was observed. Pre-transition was also affected in a greater extent by protein presence. When BSA interacted with liposomes, a smaller increase in the T values was observed with a contemporary increase of about 8 % in the associated Δ H. The data suggested that the BSA-liposomes interaction involves only the external surface of the bilayer, excluding thus any penetration into the liposomal hydrophobic core. On the contrary, a partial penetration into the bilayer is suggested when Lyso is added to liposomes. Both considered proteins strengthened the overall bilayer structure of DMPC liposomes, suggesting a decrease in the membrane permeability. Moreover, Lyso secondary structure changed by interaction with liposomes, as demonstrated by the Raman spectra behaviour, in particular in the case of DMPE. [ABSTRACT FROM AUTHOR]

A serious problem in the production of gas turbine blades is the detection of residual ceramic cores inside the cooling passages; in fact, the presence of even small ceramic pieces affects turbine performance and may cause difficulties in successive manufacturing. Therefore, it is important to have a non-destructive technique that must be capable of detecting tiny ceramic fragments in a fast and easy way. In this perspective, the suitability of infrared thermography was investigated within cooperation between the University of Naples and the Europea Microfusioni Aerospaziali S.p.A. (EMA). Several blades of three different types were inspected revealing that in many cases infrared thermography can discover small ceramic fragments which were missed by X-ray inspection. In addition, infrared thermography allows gaining of information about other types of anomalies (e.g., surface defects) during the same testing step (by eventually changing the test parameters) and then saving time and money. The obtained results look promising in view of introducing infrared thermography among industrial instrumentation as an alternative to, or integrated with, the most currently utilized non-destructive techniques. [ABSTRACT FROM AUTHOR]