Toxigenic Fusarium species and Mycotoxins Associated with Head Blight in Small-Grain Cereals in Europe

The Fusarium species predominantly found associated with Fusarium head blight (FHB) in wheat and other small-grain cereals all over Europe are F. graminearum, F. avenaceum and F. culmorum. Among the less frequently encountered species are several others which are less pathogenic or opportunistic, but also toxigenic. These include F. poae, F. cerealis F. equiseti F. sporotrichioides F. tricinctum and, to a lesser extent, F. acuminatum F. subglutinans F. solani F. oxysporum F. verticillioides F. semitectum and F. proliferatum. The species profile of FHB is due to several factors, primarily climatic conditions, particularly rain and the temperature at flowering stage, but also agronomic factors, such as soil cultivation, nitrogen fertilization, fungicides, crop rotation, and host genotype. The most frequently encountered Fusarium mycotoxins in FHB in Europe has proved to be deoxynivalenol and zearalenone produced by F. graminearum and F. culmorum with the former more common in southern (warmer) and the latter in northern (colder) European areas. Nivalenol was usually found associated with deoxynivalenol and its derivatives (mono-acetyldeoxynivalenols), together with fusarenone-X, formed by F. graminearum F. cerealis F. culmorum and, in northern areas, by F. poae. Moreover, from central to northern European countries, moniliformin has been consistently reported, as a consequence of the widespread distribution of F. avenaceum whereas the occurrence of T-2 toxin derivatives, such as T-2 toxin and HT-2 toxin, and diacetoxyscirpenol have been recorded in conjunction with sporadic epidemics of F. sporotrichioides and F. poae. Finally, beauvericin and various enniatins have recently been found in Finnish wheat colonized by F.avenaceum and F. poae.     

PCR Assay for Identification of Aspergillus Carbonarius and Aspergillus Japonicus

Black Aspergilli, and in particular Aspergillus carbonarius, are the main causes of contamination of grapes and their by-products by ochratoxin A. A PCR-based method was developed to detect DNA of A. carbonarius and A. japonicus. Two pairs of primers (CARBO1/2 and JAPO1/2) designed from the calmodulin gene, produced PCR products of 371 and 583 bp for A. carbonarius and A. japonicus, respectively. Primer specificity was tested with DNA of 107 strains belonging to Aspergillus section Nigri isolated mostly from grapes in Europe. The sensitivity of primers CARBO1/2 and JAPO1/2 was 12.5 pg when using pure total genomic DNA of the two species. The developed primers provide a powerful tool for detection of the main ochratoxigenic producing Aspergillus species in grapes.     

Antimicrobial activity and cytotoxicity of Cirsium tenoreanum

The methanol and ethyl acetate extracts of the aerial parts of Cirsium tenoreanum, have been evaluated for their phytochemical constituents and antibacterial and cytotoxic properties. Three flavonoids, apigenin, quercetin-3-O-galactoside and kaempferol-3-O-ramnoside, were isolated. The ethyl acetate extract showed a good antiproliferative activity.     

Endotoxin Structures in the Psychrophiles Psychromonas marina and Psychrobacter cryohalolentis Contain Distinctive Acyl Features

Lipid A is the essential component of endotoxin (Gram-negative lipopolysaccharide), a potent immunostimulatory compound. As the outer surface of the outer membrane, the details of lipid A structure are crucial not only to bacterial pathogenesis but also to membrane integrity. This work characterizes the structure of lipid A in two psychrophiles, Psychromonas marina and Psychrobacter cryohalolentis, and also two mesophiles to which they are related using MALDI-TOF MS and fatty acid methyl ester (FAME) GC-MS. P. marina lipid A is strikingly similar to that of Escherichia coli in organization and total acyl size, but incorporates an unusual doubly unsaturated tetradecadienoyl acyl residue. P. cryohalolentis also shows structural organization similar to a closely related mesophile, Acinetobacter baumannii, however it has generally shorter acyl constituents and shows many acyl variants differing by single methylene (-CH₂-) units, a characteristic it shares with the one previously reported psychrotolerant lipid A structure. This work is the first detailed structural characterization of lipid A from an obligate psychrophile and the second from a psychrotolerant species. It reveals distinctive structural features of psychrophilic lipid A in comparison to that of related mesophiles which suggest constitutive adaptations to maintain outer membrane fluidity in cold environments.     

Solid olive residues: insight into their phenolic composition

Solid olive residues (SOR) are byproducts of the olive-milling process, but they have an increasing importance in the pharmaceutical industry due to their rich content of biophenols. Such compounds are studied widely for their antioxidant and antimicrobial activities, but there is a lack of information about their quantitative recovery. This research highlighted the key role played both by the selection of the cultivar and by the degree of olive fruit ripening on the phenolic content on the SOR. The extraction methods were selected to reach the best quantitative results mainly using a safe food solvent. In light of the results the Soxhlet extraction with ethanol could be proposed as preferential for a higher recovery of verbascoside and its analogues.     

A chemometric approach to the comparison of different sample treatments for metals determination by atomic absorption spectroscopy in aceto Balsamico tradizionale di Modena

A comparison of different digestion procedures has been carried out for the analysis of metal concentration in samples of vinegars and Aceto Balsamico Tradizionale of Modena (ABTM) coming from an unique barrel set. In particular, classical wet, dry ashing, and closed vessel microwave digestion procedure have been utilized and compared for each investigated species. In a few cases, direct metal determination on ABTM (without treatment procedure) is proposed as possible alternative to sample manipulation. Flame atomic absorption spectrometry was used for the quantification of iron and zinc, while graphite furnace atomic absorption spectrometry was used for all the other elements (i.e., chromium, manganese, cobalt, nickel, copper, cadmium, and lead). The comparison among the different sample treatments was carried out by the use of statistical and chemometric tools. In particular, principal component analysis and ANOVA approaches were used to discriminate between the diverse analytical methods. Furthermore, for all the dissolving techniques, the analytical metal recovery was always evaluated by the application of the recovery function on the same sample matrix. In general, the recoveries were fairly good, ranging from 90 to 103%, except for Cd and Pb with dry ashing, which showed recovery values close to 55% and 67%, respectively. As regards the metals concentration of the investigated samples, the experimental data reveal for some species the presence of concentration slightly over the legal limit fixed for wine and wine vinegar.     

Survey onYersinia Enterocolitica and related bacteria in shellfish

Results from examining shellfish collected from ‘safe’ (2–34Escherichia coli/100 mL) and ‘unsafe’ (> 34E. coli/100 mL) waters for the presence ofYersinia enterocolitica and related bacteria are reported. The recovery of these microorganisms was low in bivalve mollusks destined for food consumption, high in those derived from prohibited areas. No human pathogenic bio-serogroup f Yersinia was found during the entire survey.     

Transgenic fertile soybean plants derived from somatic embryos transformed via the combined DNA-free particle bombardment and <Emphasis Type="Italic">Agrobacterium</Emphasis> system

An Agrobacterium-mediated transformation procedure for soybean [Glycine max L. Merrill] proliferating somatic embryos is here described. The Agrobacterium tumefaciens LBA4404 strain harboring pTOK233, pCAMBIA1390-olp or pH7WG2Dwrky plasmids was used to mediate gene transfer into the plant genome. Prior to Agrobacterium inoculation, proliferative soybean embryogenic clusters were microwounded by DNA-free tungsten particle bombardment. Three independent transformation experiments were performed. In Experiment I, 26 transgenic plants were obtained from a unique clone of cv Bragg, while 580 plants were recovered from 105 clones of cv IAS5. In Experiment II, a single hygromycin-resistant clone of cv BRSMG68 Vencedora was recovered and gave rise to five plants. In Experiment III, 19 plants of cv Bragg and 48 plants of IAS5 were recovered, representing five and 14 independent transformation events, respectively. PCR and Southern analyses confirmed the transgenes’ integration into plant genomes. Transgenic plants were fertile. They flowered, set pods and seeds. Transgene segregation in two T₁ progenies fits the Mendelian pattern (3:1 transgenic:non-transgenic plants). This is the first report of transgenic fertile soybean plants obtained from somatic embryogenic tissues transformed by the system that combines DNA-free particle bombardment and Agrobacterium.     

Pre-unfolding resonant oscillations of single green fluorescent protein molecules

Fluorescence spectroscopy of a green fluorescent protein mutant at single-molecule resolution has revealed a remarkable oscillatory behavior that can also be driven by applied fields. We show that immediately before unfolding, several periodic oscillations among the chemical substates of the protein chromophore occur. We also show that applied alternating electric or acoustic fields, when tuned to the protein characteristic frequencies, give rise to strong resonance effects.