Rock fragments in soil support a different microbial community from the fine earth

Two sandstone-derived soils under pure stands of silver fir (Abies alba Mill.) and European beech (Fagus sylvatica L.) were studied to determine if the fine earth (<2 mm material) and two size-classes of porous rock fragments (>2 mm material) supported different microbial communities. Samples from three soil horizons (A, Bw, and BC) were analysed under both optical and scanning electron microscopes. Small stones (2-10 mm in average diameter) appeared more altered than larger ones (40-60 mm) and the effects of weathering became more obvious with shallower depth. In both soils, numerous hyphae and other living forms were observed on the surface of the stones from the A and Bw horizons; this contrasted with the stones from the BC horizon, which showed little or no colonisation. The microbial community of each fraction was characterised using Biolog-Community Level Physiological Profiles (CLPP) and phospholipid fatty acid analyses (PLFA) for samples in the A and B horizons. Significant potential microbial activity (C source utilisation) was associated with rock fragments, from the A horizon and, to a lesser extent, the B, although this was lower than for the equivalent fine earth fraction. The microbial colonisation of the stones appeared inversely related with their size and sampling depth. The PLFA analysis showed not only quantitative differences in the microbial biomass between horizons and size-fractions but also highlighted that the communities differed between soils, horizons (for the sole beech soil) and fractions. These findings demonstrate that by considering rock fragments as a microbiologically inert fraction and discarding them before analysis, as usually is done, can lead to an incomplete picture of both the total amount and, perhaps more importantly, the structure of soil microbial community.     

Effect of industrial processing on the distribution of aflatoxins and zearalenone in corn-milling fractions

The aim of this study was to investigate the distribution of aflatoxins and zearalenone levels in various corn-milling fractions. Corn kernels and six derived milling fractions (germ, bran, large and small grits, flour, and animal feed flour) were sampled in an industrial plant; both conventional and organic corns were sampled. To evaluate the effect of cooking, samples of polenta were prepared starting from naturally contaminated flour. Conventional and organic lots showed mycotoxin contamination. For both lots, germ, bran, and animal feed flour showed a marked concentration factor from 239 to 911% accounting for both the low yields of the derived products and the distribution of aflatoxins and zearalenone contamination in the outer parts of the kernels. Conversely, a reduction factor of at least four times from raw material to finished products was observed. Polenta samples were unaffected by the cooking process, with levels of contamination similar to those of starting flour.     

Genetic variation for phenolic acids concentration and composition in a tetraploid wheat (<Emphasis Type="Italic">Triticum turgidum</Emphasis> L.) collection

Phenolic acid intake through the consumption of whole-wheat foods provides important health benefits associated with reduced risks of cardiovascular diseases and colon cancer. The genetic variation for phenolic acids was extensively studied in common wheat, but a comprehensive survey in tetraploid wheat is lacking. In this study we evaluated the genetic variability for individual and total phenolic acids concentration existing in a large collection of tetraploid wheat (Triticum turgidum L.). A 2-year evaluation was undertaken on the whole-meal flour of 111 genotypes belonging to seven T. turgidum subspecies including cultivars, landraces and wild accessions. Durum cultivars [T. turgidum subsp. durum (Desf.) MacKey], had the highest average concentration of total phenolic acids (828.7 μg g^?1 dm in 2012; 834.5 μg g^?1 dm in 2013) with amounts varying from 550.9 μg g^?1 dm to 1701.2 μg g^?1 dm, indicating a variation of greater than threefold fold. The lowest concentration of phenolic acids was found in T. turgidum subsp. dicoccum (Schrank ex Schübler) Thell. Rivet wheat (T. turgidum L. subsp. turgidum) had phenolic acid concentrations similar to those in durum, but less variation was noted among the accessions. On the other hand, the accessions of the four remaining subspecies showed lower phenolic acid concentrations and variation among the accessions as compared to durum. A total of six phenolic acids were identified across the wheat genotypes. The effects of genotype, year and year × genotype were estimated by ANOVA and resulted significant for all phenolic acids. The ratio of genotypic variance to total variance suggested the possibility of improving phenolic acid content in elite wheat germplasm through appropriate breeding programs. Moreover, significant correlations between phenolic acids and other quality characteristics of the grain were detected.     

Influence of different mineral and Organic pesticide treatments on Cd(II), Cu(II), Pb(II), and Zn(II) contents determined by derivative potentiometric stripping analysis in Italian white and red wines

This paper deals with the use of derivative potentiometric stripping analysis (dPSA) as a rapid and precise method to determine Cd(II), Cu(II), Pb(II), and Zn(II) levels in red and white wine samples from Sicily, Campania, and Tuscany and to investigate the possible connection between the content of these metals and the pesticide treatments used in vine-growing to control plant diseases and pests. dPSA allowed direct quantitation of heavy metals in acidified wines without any sample pretreatment. Mean recoveries of Cd(II), Cu(II), Pb(II), and Zn(II) ranged from 95.5 to 99.2% for white wine samples and from 96.1 to 100.0% for red wine samples. The obtained results showed that Cd(II) was not found in any sample and that Cu(II), Pb(II), and Zn(II) levels were always lower than the toxicity limits in both fungicide- and water-treated wines. Nevertheless, the contents of metals were increased in samples from organic and inorganic pesticides treatment with respect to the water-treated samples. In particular, quinoxyfen, dinocap-penconazole, and dinocap applications considerably increased Cu(II) and Zn(II) contents in white and red wines. The levels of lead were significantly raised by azoxystrobin and sulfur treatments.     

Statistical characterization of sicilian olive oils from the Peloritana and Maghrebian zones according to the fatty acid profile

This paper deals with the characterization of 475 Sicilian virgin olive oils (VOO) produced in 10 different crop years (from 1993 to 2004), according to the cultivar and the geographical origin by means of multivariate statistical analysis applied to fatty acids. In particular, the studied VOOs came from the Peloritana and Maghrebian geological zones. The fatty acid composition was determined by using the official gas chromatographic method. The results suggest that although the effect of the cultivar is significant in the olive oil classification based on the fatty acid composition, a predominant and well-defined geographic effect is also present. This study demonstrated that it is possible to employ an official and inexpensive analytical method coupled with the statistical analysis to ascertain the geographical origin and the cultivar of an extra virgin olive oil.     

Isolation of novel microsatellite loci in Orchesella villosa (Arthropoda, Collembola)

An experimental procedure using biotin-labelled probes and streptavidin-bound magnetic beads (FIASCO) was used to produce a microsatellite-enriched library for the collembolan Orchesella villosa. PCR primers were successfully constructed for seven loci containing, respectively, five pure, one interrupted, and one compound dinucleotide microsatellite repeats. As a preliminary test of their variability, we investigated 15 individuals from 5 locations inside a dismissed mining area in southern Tuscany. All microsatellite loci showed high levels of polymorphism. The mean number of different alleles at each locus across populations was 10.1 and observed heterozygosity per locus was 0.13–0.86. Only 2 out of the 7 loci appeared to be in Hardy–Weinberg equilibrium. The potential application of these loci to test the effects of environmental contamination on the genetic structure of exposed populations is discussed.     

Development of Specific PCR Primers for Identification and Detection of Rhizopycnis vagum

Rhizopycnis vagum is a recently described coelomycete known to belong to the complex of root rot pathogens contributing to vine decline of cucurbits in several parts of the world. However, the fungus has also been reported to infect tomato, and as an endophytic associate of mycorrhizal roots of wild, asymptomatic Pinus halepensis and Rosmarinus officinalis plants in Italy. To accelerate epidemiological and ecological investigations on this fungus, a PCR primer pair was developed. Primers Rv1-F and Rv1-R were designed, based on alignment of internal transcribed spacer (ITS) sequences (ITS1-5.8S-ITS2), which amplified a 396-bp fragment from all R. vagum isolates tested, including isolates pathogenic to melons and endophytic isolates from mycorrhizae. Specificity of the primer pair was verified both in silico (BLAST searches using each primer string as a query) and in PCR assays, where the primers failed to amplify DNA from any isolate of fungi taxonomically related to R. vagum (e.g. Massarina walkeri and Stagonospora spp.) and other vine decline and common soilborne pathogens (e.g. Monasporascus cannonballus, Acremonium cucurbitacearum, Fusarium spp. and Rhizoctonia solani). Under optimum conditions, detectable amplification of the specific sequence required 0.05 pg of target DNA. Amplification of the expected 369-bp fragment was also obtained from DNA root extracts of nearly asymptomatic Cucumis melo plants inoculated with R. vagum under greenhouse conditions.     

Evidence for quantitative trait locus for conformation traits on chromosome 19 in beef cattle

A total of 110 F₁ crossbred individuals of Piemontese × Chianina cattle and 75 F₂ intercross were genotyped for the DNA marker IDVGA-46, composed of an (AC) repeat, that showed a polymorphism of three alleles: 205, 207 and 229 base pairs. Association of marker polymorphism to beef conformation measures was tested with a linear mixed model which included the fixed effect of the marker genotype separated according to the origin of the allele: whether inherited from Piemontese or from Chianina and random additive genetic effect of the animals. Carriers of allele 205, when inherited from Chainina, were larger than carriers of 207 and showed a globally better body structure. No significant association was found in the animals that had inherited the alleles from Piemontese. It would be interesting to verify, in the chromosome portions flanking the mentioned marker (chromosome 19; q16 band), the existence of eventual coding sequences influencing growth and conformation.     

Paraneoplastic hypoglycemia in a diabetic dog with an insulin growth factor-2-producing mammary carcinoma

A 6-year-old intact female Labrador Retriever had diabetes mellitus, which had been difficult to control with insulin. The dog also had a solid ductal mammary carcinoma with very rapid growth, which was temporally related to onset of hypoglycemia. Eight months after initial diagnosis of diabetes, the dog had a hypoglycemic crisis. Insulin administration was stopped and serum glucose concentration returned to normal. Three months after discontinuing insulin, another hypoglycemic crisis occurred. During subsequent months, serum glucose concentrations remained at life-threatening levels (1.64-2.12 mmol/L, reference interval 4.44-6.66 mmol/L) simultaneously with an increase in the size of the mammary tumor, which reached a diameter of about 16 cm. At the time of surgery for removal of the tumor serum glucose concentration was 2.20 mmol/L and was then monitored every 3 hours after excision of the tumor. The glucose concentration continued to rise and reached 9.99 mmol/L 12 hours after the removal of the mammary tumor. Immunohistochemical staining demonstrated expression of insulin growth factor-2 by tumor cells, which apparently had caused the hypoglycemia during tumor growth even in a diabetic dog. Hyperglycemia associated with diabetes was pronounced after excision of the tumor and had been masked by the paraneoplastic effect of the tumor.