Aflatoxin contamination in nuts marketed in Italy: preliminary results.

BACKGROUND: Aflatoxins (AFs) are one of the main groups of mycotoxins produced by molds. Nuts, although recognized as a food with health benefits, are frequently contaminated by AFs. STUDY DESIGN: In this preliminary study we evaluated the contamination by total AFs and AFB1 in different types of nuts from different countries marketed in Apulia. METHODS: Overall, 124 samples (almonds, apricot kernels, chestnuts, hazelnuts, peanuts, pistachios, walnuts and Brazil nut) were analyzed using an High-Performance Liquid Chromatography system. RESULTS: Twenty samples (16.1%) were contaminated with AFs of which 55% were non-compliant, according to Reg. 165/2010. The median values (µg/kg) of total AFs and AFB1 were 16.6 and 15.1, respectively. Pistachios appeared more susceptible to AF contamination than the other nuts, with levels of total AFs ranging from 8.8 to 387.3 µg/kg and of AFB1 from 8.2 to 354.5 µg/kg. The majority of contaminated samples came from Asia and AF contamination was different in the various Asiatic sub-regions: regardless of the type of nuts, samples from Western Asia were the least contaminated. CONCLUSIONS: As geographical origin may influence the risk of contamination, in order to protect human health, customer countries should increase AF monitoring in nuts coming from those countries with favorable environments for the growth of aflatoxigenic molds or with less strict regulations.

Electronic nose and isotope ratio mass spectrometry in combination with chemometrics for the characterization of the geographical origin of Italian sweet cherries.

Sweet cherries from two Italian regions, Apulia and Emilia Romagna, were analysed using electronic nose (EN) and isotope ratio mass spectrometry (IRMS), with the aim of distinguishing them according to their geographic origin. The data were elaborated by statistical techniques, examining the EN and IRMS datasets both separately and in combination. Preliminary exploratory overviews were performed and then linear discriminant analyses (LDA) were used for classification. Regarding EN, different approaches for variable selection were tested, and the most suitable strategies were highlighted. The LDA classification results were expressed in terms of recognition and prediction abilities and it was found that both EN and IRMS performed well, with IRMS showing better cross-validated prediction ability (91.0%); the EN-IRMS combination gave slightly better results (92.3%). In order to validate the final results, the models were tested using an external set of samples with excellent results.

Non-targeted 1H NMR fingerprinting and multivariate statistical analyses for the characterisation of the geographical origin of Italian sweet cherries.

In this study, non-targeted (1)H NMR fingerprinting was used in combination with multivariate statistical techniques for the classification of Italian sweet cherries based on their different geographical origins (Emilia Romagna and Puglia). As classification techniques, Soft Independent Modelling of Class Analogy (SIMCA), Partial Least Squares Discriminant Analysis (PLS-DA), and Linear Discriminant Analysis (LDA) were carried out and the results were compared. For LDA, before performing a refined selection of the number/combination of variables, two different strategies for a preliminary reduction of the variable number were tested. The best average recognition and CV prediction abilities (both 100.0%) were obtained for all the LDA models, although PLS-DA also showed remarkable performances (94.6%). All the statistical models were validated by observing the prediction abilities with respect to an external set of cherry samples. The best result (94.9%) was obtained with LDA by performing a best subset selection procedure on a set of 30 principal components previously selected by a stepwise decorrelation. The metabolites that mostly contributed to the classification performances of such LDA model, were found to be malate, glucose, fructose, glutamine and succinate.

Instrumental and multivariate statistical analyses for the characterisation of the geographical origin of Apulian virgin olive oils.

In this paper, virgin olive oils (VOOs) coming from three different geographic origins of Apulia, were analysed for free acidity, peroxide value, spectrophotometric indexes, chlorophyll content, sterol, fatty acid, and triacylglycerol compositions. In order to predict the geographical origin of VOOs, different multivariate approaches were applied. By performing principal component analysis (PCA) a modest natural grouping of the VOOs was observed on the basis of their origin, and consequently three supervised techniques, i.e., general discriminant analysis (GDA), partial least squares-discriminant analysis (PLS-DA) and soft independent modelling of class analogy (SIMCA) were used and the results were compared. In particular, the best prediction ability was produced by applying GDA (average prediction ability of 82.5%), even if interesting results were obtained also by applying the other two classification techniques, i.e., 77.2% and 75.5% for PLS-DA and SIMCA, respectively.

Leaping ability and body composition in rhythmic gymnasts for talent identification.

AIM: Aim of this study was to investigate leaping ability and morphological characteristics in rhythmic gymnastics, in order to verify which parameters are useful indicators for the talent identification. METHODS: Twenty-five national gymnasts of international level (age 14.7+/-2.2 years) underwent three testing sessions: anthropometric measurements, vertical jumps (counter movement jump and hopping test), and three technical split leaps with stretched legs (SL), with ring (RG) and with back bend of the trunk (BBT). RESULTS: Elite had significantly different values (P < 0.05) of stature (1.65+/-0.03 vs 1.55+/-0.09 m), thigh length (0.42+/-0.03 vs 0.39+/-0.02 m) and FFM(42.42+/-2.81 vs 35.84+/-5.66 kg) compared to sub-elite. The height of hopping test was significantly higher in elite than sub-elite gymnasts (0.34+/-0.05 vs 0.27+/-0.04 m; P < 0.05), but no significant differences in counter movement jump between two groups were found. Ground contact time of hopping test was significantly correlated (P < 0.01) with SL (r = 0.613), RG (r = 0.632), and BBT (r = 0.542) values. By multiple regression analysis, among anthropometric and vertical jump variables, the hopping ground contact time was the strongest predictor of ground contact time of the three technical leaps (SL, RG, BBT) accounting for 26-37% of variance. CONCLUSION: Some anthropometric measurements are good indicators for the better performance in rhythmic gymnastics. Level of muscle compliance (stiffness) evaluated by hopping test is a good parameter for athletes selection and for monitoring leaps training.

Somatotype in 6-11-year-old Italian and Estonian schoolchildren.

The study of somatotypes can contribute to the understanding of variability in human body build. The aim of this study was to compare the somatotypes of Italian and Estonian schoolchildren in order to evaluate factors that might lead to variability in somatotypes. The sample consisted of 762 Italian and 366 Estonian children aged 6-11 years. They were somatotyped by the Heath-Carter anthropometric method. Data on organised extra-curricular physical activity and hours of weekly training were also collected. One-way ANOVA was used to evaluate country-related variations of somatotype in each age/sex group, while factorial ANOVA was used to test the influence of country and organised physical activity on the variability of the anthropometric characteristics and somatotype components. There are significant differences in mean somatotypes between the Italian and Estonian children in many age classes and a different constitutional trend in children from the two different countries is observed. The Italian children are more endomorphic and less mesomorphic and ectomorphic than the Estonian children. On the other hand, it emerges from factorial ANOVA, that the somatotype components do not present significant variations related to organised physical activity and to the interaction between the country of origin and sport practice. Moreover, the results of the forward stepwise discriminant analyses show that mesomorphy is the best discriminator between the two countries, followed by ectomorphy. Our findings suggest that the observed differences between Italian and Estonian children could be related mainly to country rather than to the practice of organised physical activity in the two countries.

Effect of aggregation state, temperature and phospholipids on photobleaching of photosynthetic pigments in spinach Photosystem II core complexes.

Photosystem II (PSII) complex activity is known to decrease under strong white light illumination, and this photoinhibition phenomenon is connected to the photobleaching of the PSII photosynthetic pigments. In this work the pigment photobleaching has been studied on PSII core complexes, by observing the effects of different factors such as the aggregation state (PSII monomers and dimers were used), temperature (20 degrees C and 10 degrees C temperatures were tested) and the presence of the exogenous phospholipids (cardiolipin and phosphatidylglycerol). In particular, PSII resistance against white light stress was studied by means of UV/VIS Absorption and Fluorescence Emission measurements. It was found that PSII dimers resulted more resistant against photobleaching and that lower temperature reduces the pigment photodestruction. Moreover, the presence of phosphatidylglycerol or cardiolipin enhanced the PSII resistance to the photobleaching phenomenon, mainly at lower temperatures.

Isolation and characterization of lipids strictly associated to PSII complexes: focus on cardiolipin structural and functional role.

In this work, lipid extracts from spinach membrane fragments enriched in Photosystem II (PSII) and from spinach PSII dimers were analyzed, by means of Thin Layer Chromatography (TLC) and Electro-Spray Ionization Mass Spectrometry. Cardiolipin found in association with PSII was isolated and purified by preparative TLC, then characterized by mass and mass-mass analyses. Cardiolipin structures with four unsaturated C18 acyl chains and variable saturation degrees were evidenced. Structural and functional effects of different phospholipids on PSII complexes were investigated by Fluorescence, Resonance Light Scattering and Oxygen Evolution Rate measurements. An increment of PSII thermal stability was observed in the presence of cardiolipin and phosphatidylglycerol.

Focus on the aggregation processes of Photosystem II complexes.

In this work the effect of temperature and n-dodecyl-beta-d-maltoside (DM) on PSII complexes organization was investigated. An aggregation process of PSII monomers and dimers was documented at different temperatures and low DM concentration by steady-state fluorescence, absorption, circular dichroism, Rayleigh and dynamic light-scattering experiments. Measures of oxygen evolution enabled us to estimate the change in photoactivity of PSII during the aggregation. This process was found to be extensively reversed by increasing DM concentration as proved by means of steady-state fluorescence and dynamic light-scattering experiments.

Lipid content in higher plants under osmotic stress.

In this work, we performed investigations on the lipid content of higher plants (spinach) under hyperosmotic stress, by means of thin layer chromatography (TLC) and mass spectrometry. In particular, the experiments have been performed at different plant organization levels: whole leaves, freshly prepared protoplast suspension and mesophyll cells obtained by reformation of the cell wall from protoplast suspension. The results obtained showed that hyperosmotic stress induces changes in the phospholipid content depending on the different plant organization levels studied. All phospholipids showed an increment of their content in stressed whole leaves. In particular, phosphatidylglycerol (PG) redoubles its content by 1 h of osmotic shock. Different responses to hyperosmotic stress were reported for the other systems. In the case of protoplasts, an increment of PG, phosphatidylcholine (PC) and phosphatidylinositol (PI) together with biphosphatidylglycerol (BPG) and phosphatidylethanolamine (PE) content decreasing were observed in stressed sample. For PG, identified as PG (34:4) by elecrospray ionization mass spectrometry, the increment was of about 30%. In the case of cells, conversely, a decrease of PG content under osmotic stress was recorded. The results suggest an important role of phospholipids, in particular of PG, in the osmotic stress response.