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Highlights: [•] Human and rat colon tracts are sensitive to fumonisins toxicity. [•] Reduction of short circuit current (Isc) induced by fumonisins-free chyme on colon tract. [•] No Isc modifications induced by fumonisins contaminated corn chyme sample on colon tract. [ABSTRACT FROM AUTHOR]

This work aimed to select heat-resistant probiotic lactobacilli to be added to Fior di Latte (high-moisture cow milk Mozzarella) cheese. First, 18 probiotic strains belonging to Lactobacillus casei, Lactobacillus delbrueckii ssp. bulgaricus, Lactobacillus paracasei, Lactobacillus plantarum, Lactobacillus rhamnosus, and Lactobacillus reuteri were screened. Resistance to heating (65 or 55°C for 10 min) varied markedly between strains. Adaptation at 42°C for 10 min increased the heat resistance at 55°C for 10 min of all probiotic lactobacilli. Heat-adapted L. delbrueckii ssp. bulgaricus SP5 (decimal reduction time at 55°C of 227.4 min) and L. paracasei BGP1 (decimal reduction time at 55°C of 40.8 min) showed the highest survival under heat conditions that mimicked the stretching of the curd and were used for the manufacture of Fior di Latte cheese. Two technology options were chosen: chemical (addition of lactic acid to milk) or biological (Streptococcus thermophilus as starter culture) acidification with or without addition of probiotics. As determined by random amplified polymorphic DNA-PCR and 16S rRNA gene analyses, the cell density of L. delbrueckii ssp. bulgaricus SP5 and L. paracasei BGP1 in chemically or biologically acidified Fior di Latte cheese was approximately 8.0 log10 cfu/g. Microbiological, compositional, biochemical, and sensory analyses (panel test by 30 untrained judges) showed that the use of L. delbrueckii ssp. bulgaricus SP5 and L. paracasei BGP1 enhanced flavor formation and shelf-life of Fior di Latte cheeses. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to assess the natural exposure of male horses (Equus caballus) to the mycotoxin zearalenone (ZEA) by using the ELISA test and to evaluate the effects of in vitro exposure of sperm cells to mycotoxin-containing urine extracts on sperm chromatin structure stability. Because of their occurrence in urine samples, ZEA and its derivatives were tested by sperm chromatin structure assay (SCSA) at natural levels detected by ELISA. Thirty-eight urine extracts of Italian (n = 11) and northeastern European (n = 27) horses were tested on frozen-thawed spermatozoa to evaluate the toxic effect of mycotoxin on their chromatin structure by flow cytometry. Different parameters of the DNA fragmentation index (DFI), such as the mean (), the percentage (%-DFI), and the standard deviation (SD-DFI), were analyzed. Urine samples showed a mean level of 32.3 ng/mL ZEA with significantly higher concentrations in northeastern European samples than in Italian samples, probably in relation to climatic and feeding differences. The toxic effects of ZEA-containing urine samples on SCSA parameters were found at low ZEA concentrations and were mainly observed in Italian samples. By using mycotoxin standards, ZEA, α-zearalenol, and β-zearalenol proved to be more toxic compounds for sperm chromatin stability than other tested derivatives. A nongenomic mechanism of action can be hypothesized. [Copyright &y& Elsevier]

Abstract: Zearalenone (ZEA) is a fusariotoxin naturally occurring in crops with known estrogenic activity in swine, the most sensitive known species. The metabolism by swine of ZEA, principally into α-zearalenol (α-ZOL), is considered as a bio-activation because of its high affinity with estrogenic receptors. Discordant data on male reproductive failures induced by ZEA in vivo are described. In this study, we evaluated the effects to boar spermatozoa when they are exposed in vitro to ZEA and its derivatives (α-ZOL, β-ZOL). We analyzed viability, apoptosis (terminal deoxynucleotidyltransferase dUTP nick end-labelling (TUNEL)), sperm chromatin stability (sperm chromatin structure assay (SCSA)) and motility (using computer-aided sperm analysis (CASA)). Each mycotoxin influenced a specific function of spermatic cells. α-Zearalenol and ZEA, at picomolar levels, negatively influenced chromatin structure stability and viability, respectively, whereas β-ZOL negatively influenced the sperm motility at micromolar levels. This study is the first using these direct measures of sperm integrity to show the potential for an adverse effect of ZEA exposure on boar fertility. [Copyright &y& Elsevier]

The toxicity of the mycotoxins nivalenol (NIV), deoxynivalenol (DON) and fumonisin B1 (FB1) were studied in the K562 human erythroleukemia cell line using the Trypan Blue, MTT and BrdU uptake analyses of cytotoxicity, cell metabolism and cell proliferation, respectively. Nuclear staining with propidium iodide and DNA analysis by flow cytometry were used to identify apoptosis and cell cycle distribution. By the MTT and BrdU tests, both NIV and DON were significantly more toxic than FB1 by at least one order of magnitude, with ID50s ranging from 0.5 μM for NIV to 70 μM for FB1. The MTT test indicated that NIV was significantly (approximately four times) more toxic than DON. In contrast, the Trypan Blue test did not reveal any effects of mycotoxin exposure suggesting that, at the concentrations tested, NIV, DON and FB1 did not induce cytotoxicity through plasma membrane damage. Cell cycle analysis suggested apoptotic cytotoxicity, revealing 100% cellular debris at the highest concentrations of NIV and DON and approximately 2.9 times more debris than control at the highest FB1 concentration. Morphological evidence of apoptosis was related to the toxicity of the substances, such that the more toxic NIV and DON resulted in more late stage apoptotic events than FB1. This study suggests that human blood cells are sensitive to mycotoxin exposure, that NIV is more toxic than DON which is more toxic than FB1, and that DNA damage and apoptosis rather than plasma membrane damage and necrosis may be responsible for the observed cytotoxicity. [Copyright &y& Elsevier]

White table grape cv. Italia is a typical component of the Mediterranean diet and a source of phenolic compounds, particularly abundant in the skin portion. The aim of this study was to characterize the phenolic profile of the table grape skin and to assess its stability after the in vitro digestion process. The main phenolic compounds identified by the HPLC-DAD analysis were: procyanidin B 1 , caftaric acid, catechin, coutaric acid, quercetin 3-glucuronide and quercetin 3-glucoside. All compounds showed a good stability after in vitro digestion (from 43 to 80%). Moreover, the influence of grape skin polyphenols on the modulation of ROS and GSH levels was evaluated in basal and in stressed conditions on human intestinal cells (HT-29). In basal conditions, a higher polyphenol concentrations exerted pro-oxidant effect corresponding to high ROS level and low GSH content. This effect was probably due to the polyphenolic oxidation in cell culture condition with consequent production of hydrogen peroxide. Otherwise, in stressed conditions, grape skin polyphenols exerted antioxidant effects up to 1.3 × 10 −6  μg/g and restored the stress-related GSH reduction. The in vitro digestion process attenuated the biological effect of grape skin polyphenols on intestinal cell line (HT-29). In conclusion, grape skin polyphenols showed different behavior in relation to their concentrations and to the intracellular ROS levels. [ABSTRACT FROM AUTHOR]

Cadmium is a highly toxic heavy metal with negative effects on oocyte fertilization. The aim of this study was to analyse whether cadmium-induced impairment of fertilization is caused by mitochondria dysfunction and oxidative stress in the cumulus-oocyte complex (COC). Preliminarily, 19 trace element levels were measured in ovaries from juvenile and adult ewes and age-related cadmium ovarian bioaccumulation at nanomolar concentrations was found. COCs from juvenile and adult ewes, exposed during in vitro maturation to 1 nM or 100 nM CdCl 2 , and subjected to in vitro fertilization showed significantly lower fertilization rates in exposed COCs compared with controls. In vitro matured exposed and control COCs underwent confocal microscopy analysis of mitochondria activity and reactive oxygen species (ROS) levels and lipid peroxidation (LPO) assay at cumulus cell and oocyte level. In both age groups, cadmium at nanomolar concentrations induced cumulus-oocyte mitochondria over-activity and oxidative damage which were related to impaired oocyte fertilization. [ABSTRACT FROM AUTHOR]

Fumonisins (FBs), Fusarium mycotoxins common food contaminant, are a potent inducer of oxidative stress and lipid peroxidation in intestinal cells. In order to verify this toxic effect in intestine tract, the aim was to assess lipid peroxidation (as malondialdehyde MDA increased levels) on intestine rat samples exposed to chyme samples from in vitro digestion of FBs contaminated corn samples. Naturally (9.61 ± 3.2 μg/gr), artificially (726 ± 94 μg/gr) and spiked corn samples at EU permitted FBs levels were digested and added to luminal side of Ussing chamber for 120 min. Fumonisins-free corn sample was used as control. The MDA increase was observed just in 83% of intestine samples exposed at EU FBs levels and the digestion process seems to reduce this incidence (50% of samples). Malondialdehyde levels were FBs dose- and subject-related and ranged from 0.07 ± 0.01 to 3.59 ± 0.6 nmol/mg. Highest incidence and MDA % increment ( I ) were found when intestine tracts were exposed to chymes from artificially corn sample. The induction of lipid peroxidation induced by FBs could be due to interactions between FBs and intestinal membranes, with consequent modifications in membrane permeability and oxygen diffusion–concentration, as suggested by other authors. [ABSTRACT FROM AUTHOR]

Verbascoside (VB) is a phenolic antioxidant present in different plants, but, as reported for other polyphenols, could be unstable at different pH conditions. The aim of this work was to assess how chemical modification of VB, occurring during incubation at pH values similar to gastric (pH 3) and intestinal (pH 7) conditions, may impact antioxidant activity in two human intestinal cells lines. Quali-quantitative approaches were performed in order to evaluate the specific interactions between VB and its derivatives. HPLC analysis was performed to assess possible VB transformation into derivative products. The antioxidant activity of a mixture of VB, isoverbascoside (IsoVB) and oxidized products (obtained after incubation at pH 7), or purified VB and IsoVB, was assessed in two human intestinal cell lines (HT-29 and Caco-2) using a DCFH-DA probe. VB was stable at pH 3 with a recovery of ~ 100% after 24 h. In contrast, VB was unstable at pH 7, with a loss of 62.4%, transforming into IsoVB and other oxidative products. Cellular antioxidant assays found that the mixture of oxidized VB products resulted less active (EC 50 ranging from 2.7 to 3.4 μM) than VB (EC 50 ranging from 0.24 to 0.29 μM), IsoVB (EC 50 ranging from 0.85 to 1.4 μM), and VB + IsoVB (EC 50 ranging from 0.12 to 0.21 μM). Cellular uptake of IsoVB was found to differ between cell lines, with higher uptake by Caco-2 compared to HT-29. Both graphical and mathematical methods identified different interactions between VB and IsoVB on the two cell lines. In conclusion, the antioxidant activity of VB can be modified by the conditions present in intestinal environment. [ABSTRACT FROM AUTHOR]

Abstract: The effects of mycotoxin zearalenone and their major metabolites α- and β-zearalenol on spontaneous contractions in isolated lamb uterine smooth muscle were examined. The study was carried out on 20 female prepubertal lambs aged between 45 and 50 days. Myometrial strips were set up in two isolated organ baths (10ml) at 37°C and were exposed to increasing concentrations (10−11 M–10−6 M) of these mycoestrogens and results were compared with the effect, at the same concentrations, of natural estrogen 17β-estradiol. Our findings suggest that mycotoxins and 17β-estradiol, at nanomolar concentrations, rapidly enhance phasic spontaneous smooth muscle contraction. In particular, zearalenone increases the uterine activity similarly to 17β-estradiol. On the contrary, its metabolite α-zearalenol significantly inhibits myometrial contractility. [Copyright &y& Elsevier]

Abstract: Caciocavallo Pugliese cheese was manufactured according to a traditional protocol and with added autochthonous Lactobacillus paracasei subsp. paracasei and L. parabuchneri strains, isolated from a well-flavoured Caciocavallo Pugliese cheese, to evaluate their contribution to the cheese biochemical characteristics. Using a “two step REP-PCR” protocol, L. paracasei subsp. paracasei strains were shown to sustain high viability during ripening, while the L. parabuchneri strains were not recovered. The inoculated cheese showed higher levels of free amino acids, as well as differences in the profiles of individual free amino acids in comparison with the control cheese. The addition of autochthonous Lactobacillus strains with interesting technological properties in Caciocavallo Pugliese cheese manufacturing could make it feasible to improve cheese processing, while still maintaining the sensory characteristics of this typical pasta-filata cheese. [Copyright &y& Elsevier]

Abstract: Lycopene, a non-provitaminic carotenoid, present in many fruit and vegetables, such as tomatoes and their processed products, has been associated with decreased risk of chronic diseases including cancer. The influence of lycopene on the proliferation of the breast tumour cell line (MCF-7) was tested using MTT and BrdU assays at different time intervals (from 24 to 72h) and dose–response (from 0.125 to 100μM). The induction of Gap Junction Intercellular Communication (GJIC) was evaluated by dye-transfer assay using Lucifer Yellow on monolayer cells treated with different lycopene concentrations (from 0.125 to 5μM) for 6 to 48h. The Minimal Inhibitory Concentration (MIC) of lycopene was of 5μM, after a 24h exposure. A prolonged exposure time (72h) induced a similar inhibitory effect. Lycopene stimulated the functionality of GJIC at concentrations of 1μM after 24h and this effect was dose-dependent. The induction of GJIC by lycopene was confirmed by an increased expression of connexin 43. Collectively, the above data confirm the inhibitor effects of lycopene on MCF-7 cell growth and suggest that lycopene is involved in the modulation of the gap junction intercellular communication in this cell line, as observed for other cancer cell lines. [Copyright &y& Elsevier]