Bioaccumulation of dioxin-like substances and selected brominated flame retardant congeners in the fat and livers of black pigs farmed within the Nebrodi Regional Park of Sicily

An observational study was designed to assess the bioaccumulation of polychlorodibenzodioxins (PCDD) and polychlorodibenzofurans (PCDF), dioxin-like polychlorobiphenyls (DL-PCB), and 13 selected polybromodiphenylethers (PBDE) in autochthonous pigs reared in the Nebrodi Park of Sicily (Italy). Perirenal fat and liver samples were drawn from animals representative of three different outdoor farming systems and from wild pigs and then analyzed for the chemicals mentioned previously. The highest concentrations of PCDD + PCDF and DL-PCB were detected in the fat (0.45 and 0.35 pg World Health Organization toxicity equivalents [WHO-TE] per g of fat base [FB], respectively) and livers (12.7 and 3.28 pg WHO-TE per g FB) of the wild group, whereas the free-ranging group showed the lowest levels (0.05 and 0.03 pg WHO-TE per g FB in fat and 0.78 and 0.27 pg WHO-TE per g FB in livers). The sum of PBDE congeners was highest in wild pigs (0.52 ng/g FB in fat and 5.64 ng/g FB in livers) and lowest in the farmed group (0.14 ng/g FB in fat and 0.28 ng/g FB in livers). The contamination levels in fat and livers of outdoor pigs had mean concentration values lower than those levels reported for intensively indoor-farmed animals. In wild pigs, bioaccumulation was associated with their free grazing in areas characterized by bush fires. The results of this study aid to emphasize the quality of the environment as a factor to guarantee food safety in typical processed pig meat products, specifically from outdoor and extensive Nebrodi farming systems.     

In vitro fermentation characteristics of diets with different forage/concentrate ratios: comparison of rumen and faecal inocula

BACKGROUND: The aim of this trial was to evaluate the replacement of rumen fluid with faeces as inoculum in studying the in vitro fermentation characteristics of diets for ruminants using the in vitro gas production technique. Six iso‐protein diets with different forage/concentrate ratios were incubated with rumen fluid (RI) or faeces (FI) collected from sheep. RESULTS: Most of the fermentation parameters were influenced by diet and inoculum (P < 0.01). With both inocula, organic matter degradability (dOM), cumulative gas production (OMCV) and maximum fermentation rate (R_max) increased as the amount of concentrate in the diet increased. R_max was lower with FI vs RI (P < 0.01); dOM was higher with FI vs RI and the diet × inoculum interaction was significant. As expected, with both inocula, R_max increased as the neutral detergent fibre content of the diet decreased. Significant correlations were obtained using both inocula between OMCV/dOM and gas/volatile fatty acid (VFA), while the correlation VFA/dOM was significant only with FI. The microbial biomass yield calculated by stoichiometric analysis for all diets was higher with FI vs RI. With FI the organic matter used for microbial growth showed an overall decreasing trend as the amount of concentrate in the diet increased. CONCLUSION: The results indicate that both faeces and rumen fluid from sheep have the potential to be used as inoculum for the in vitro gas production technique. Copyright © 2011 Society of Chemical Industry     

Real-time gaseous, PM and ultrafine particle emissions from a modern marine engine operating on biodiesel

Emissions from harbor-craft significantly affect air quality in populated regions near ports and inland waterways. This research measured regulated and unregulated emissions from an in-use EPA Tier 2 marine propulsion engine on a ferry operating in a bay following standard methods. A special effort was made to monitor continuously both the total Particulate Mass (PM) mass emissions and the real-time Particle Size Distribution (PSD). The engine was operated following the loads in ISO 8178-4 E3 cycle for comparison with the certification standards and across biodiesel blends. Real-time measurements were also made during a typical cruise in the bay. Results showed the in-use nitrogen oxide (NOx) and PM(2.5) emission factors were within the not to exceed standard for Tier 2 marine engines. Comparing across fuels we observed the following: a) no statistically significant change in NO(x) emissions with biodiesel blends (B20, B50); b) ～ 16% and ～ 25% reduction of PM(2.5) mass emissions with B20 and B50 respectively; c) a larger organic carbon (OC) to elemental carbon (EC) ratio and organic mass (OM) to OC ratio with B50 compared to B20 and B0; d) a significant number of ultrafine nuclei and a smaller mass mean diameter with increasing blend-levels of biodiesel. The real-time monitoring of gaseous and particulate emissions during a typical cruise in the San Francisco Bay (in-use cycle) revealed important effects of ocean/bay currents on emissions: NO(x) and CO(2) increased 3-fold; PM(2.5) mass increased 6-fold; and ultrafine particles disappeared due to the effect of bay currents. This finding has implications on the use of certification values instead of actual in-use emission values when developing inventories. Emission factors for some volatile organic compounds (VOCs), carbonyls, and poly aromatic hydrocarbons (PAHs) are reported as supplemental data.     

Volatile composition of pomegranates from 9 Spanish cultivars using headspace solid phase microextraction

Fruits of 9 Spanish pomegranate cultivars were analyzed for quality parameters, volatile composition, and sensory profile. Volatile compounds were extracted using headspace solid phase micro-extraction (HS-SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS) and flame ionization detector (GC-FID). Twenty-one compounds were found in the headspace of fresh pomegranate juices, including aldehydes, monoterpenes, and alcohols. The most abundant compounds were hexanal, limonene, trans-2-hexenal, and cis-3-hexenol. Fruits from the cultivars Mollar Elche(ME) ME14, ME1, and ME2 presented the highest values of overall liking by the consumer panel; however, their total volatiles concentration were low compared to the other pomegranate cultivars and their color intensity was intermediate. Overall consumer liking of pomegranate juices was mainly associated with the presence of monoterpenes (α-terpineol); however, high aldehydes (trans-2-hexenal) concentrations were correlated with poor overall consumer liking. Fruits from sour-sweet cultivars (PTO7 and ADO4) could improve the quality of ME pomegranate juices due to their intense color, high monoterpenes concentrations, and their moderate sourness. Practical Application: The information provided in this study proves that sour-sweet pomegranate fruits can be used in the manufacturing of pomegranate juices and will improve the sensory quality and the volatile composition of this product.     

Production of okara and soy protein concentrates using membrane technology

Microfiltration (MF) membranes with pore sizes of 200 and 450 nm and ultrafiltration (UF) membranes with molecular weight cut off of 50, 100, and 500 kDa were assessed for their ability to eliminate nonprotein substances from okara protein extract in a laboratory cross-flow membrane system. Both MF and UF improved the protein content of okara extract to a similar extent from approximately 68% to approximately 81% owing to the presence of protein in the feed leading to the formation of dynamic layer controlling the performance rather than the actual pore size of membranes. Although normalized flux in MF-450 (117 LMH/MPa) was close to UF-500 (118 LMH/MPa), the latter was selected based on higher average flux (47 LMH) offering the advantage of reduced processing time. Membrane processing of soy extract improved the protein content from 62% to 85% much closer to the target value. However, the final protein content in okara (approximately 80%) did not reach the target value (90%) owing to the greater presence of soluble fibers that were retained by the membrane. Solubility curve of membrane okara protein concentrate (MOPC) showed lower solubility than soy protein concentrate and a commercial isolate in the entire pH range. However, water absorption and fat-binding capacities of MOPC were either superior or comparable while emulsifying properties were in accordance with its solubility. The results of this study showed that okara protein concentrate (80%) could be produced using membrane technology without loss of any true proteins, thus offering value addition to okara, hitherto underutilized. Practical Application: Okara, a byproduct obtained during processing soybean for soymilk, is either underutilized or unutilized in spite of the fact that its protein quality is as good as that of soy milk and tofu. Membrane-processed protein products have been shown to possess superior functional properties compared to conventionally produced protein products. However, the potential of membrane technology has not been exploited for the recovery of okara protein. Our study showed that protein content of okara extract could be improved from approximately 68% to approximately 81% without losing any true proteins in the process.     

The effect of postharvest ripening on strawberry bioactive composition and antioxidant potential

BACKGROUND: The aim of the present work was to evaluate the phytochemical profile and the antioxidant activity of strawberry fruit (cv. Camarosa) upon postharvest ripening at room temperature (20 °C) and to correlate them with qualitative attributes. RESULTS: ‘Camarosa’ fruit retained an appreciable postharvest performance for up to 1 day shelf life; thereafter substantial quality deterioration was observed. An increased phenolic content, mainly attributed to hydroxycinnamic acids, flavonols and anthocyanins, was monitored after 3 days maintenance at 20 °C. The chromatographic fingerprint of athocyanins showed that pelargonidin‐3‐glucoside was the major anthocyanin, which increased with the increase of shelf life period, while cyanidin‐3‐glucoside and pelargonidin‐3‐rutinoside were found at lower concentrations. The potent radical scavenging activity, evaluated with four in vitro assays, showed a higher antioxidant capacity after 3 and 1 days of shelf life. In addition, the antioxidant effect of strawberry fruit extracts on lipid substrates and on an emulsion system showed a significant inhibition in the formation of conjugated diene hyperoxides. Interestingly, no direct correlation between the phytochemical profile and the quality attributes exist. CONCLUSION: ‘Camarosa’ fruit had acceptable quality attributes for fresh consumption and at the same time a high phytochemical content up to 1 day shelf life. The over‐ripe fruit continued to be an excellent reservoir of natural antioxidants, pointing to its potential use as food antioxidant and nutritional supplement. Copyright © 2011 Society of Chemical Industry     

Nutritional value and digestion rate of rhea meat proteins in association with storage and cooking processes

The nutritional value of proteins was investigated after the storage and cooking of rhea M. Gastrocnemius pars interna. Oxidation of basic and aromatic amino acids, surface hydrophobicity and aggregation state of proteins, were determined in raw and cooked meat. In addition, myofibrillar proteins were exposed in vitro to proteases of the digestive tract. Cooking markedly affected the protein surface hydrophobicity. The BBP bound content was three times greater in cooked than in fresh rhea meat. A small increment in tryptophan content after cooking was observed. Storage influenced Schiff bases formation indicating the presence of protein-aldehyde adducts after cooking. High content of Schiff bases was found after cooking of samples stored for 5 days, demonstrating a probable implication of free amino groups, most likely from lysine. Cooking decreased the myofibrillar protein susceptibility to pepsin activity. After cooking, the proteolysis rate by pancreatic enzymes increased. Our findings support the importance of protein aggregation in the nutritional value of meat proteins.     

Role of incubation conditions and protein fraction on the antimicrobial activity of egg white against Salmonella Enteritidis and Escherichia coli

The mechanism of egg white antimicrobial activity involves specific molecules and environmental factors. However, it is difficult to compare the data from the literature because of the use of various bacterial strains and incubation conditions. The aim of our study was to determine the effect of temperature, pH, inoculum size, and egg white protein concentration on egg white antimicrobial activity and to investigate the putative interactions among these factors by conducting a complete factorial design analysis. The behavior of Salmonella Enteritidis and Escherichia coli was studied after precultivation in tryptic soy broth and Luria-Bertani broth, respectively, using three different egg white protein concentrations (0, 10, and 100%), five temperatures (37, 40, 42, 45, and 48°C), two pHs (7.8 and 9.3), and six inoculum levels (3 to 8 log CFU/ml). The essential role of temperature was identified. An inverse relationship was observed between bacterial growth and an increase in temperature. The role of egg white proteins was clearly demonstrated. In the absence of egg white proteins, bacterial growth occurred under most incubation conditions, whereas the presence of 10 and 100% protein produced bacteriostatic or bactericidal effects. The interaction between temperature and protein concentration was significant. At the highest tested temperatures, proteins were less involved in the bactericidal effect. Bacterial destruction was higher at pH 9.3 than at pH 7.8. Under our experimental conditions, Salmonella Enteritidis was more resistant to inactivation by egg white than was E. coli.     

A mutation in the COX5 gene of the yeast Scheffersomyces stipitis alters utilization of amino acids as carbon source, ethanol formation and activity of cyanide insensitive respiration

Scheffersomyces stipitis PJH was mutagenized by random integrative mutagenesis and the integrants were screened for lacking the ability to grow with glutamate as sole carbon source. One of the two isolated mutants was damaged in the COX5 gene, which encodes a subunit of the cytochrome c oxidase. BLAST searches in the genome of Sc. stipitis revealed that only one singular COX5 gene exists in Sc. stipitis, in contrast to Saccharomyces cerevisiae, where two homologous genes are present. Mutant cells had lost the ability to grow with the amino acids glutamate, proline or aspartate and other non-fermentable carbon sources, such as acetic acid and ethanol, as sole carbon sources. Biomass formation of the mutant cells in medium containing glucose or xylose as carbon source was lower compared with the wild-type cells. However, yields and specific ethanol formation of the mutant were much higher, especially under conditions of higher aeration. The mutant cells lacked both cytochrome c oxidase activity and cyanide-sensitive respiration, whereas ADH and PDC activities were distinctly enhanced. SHAM-sensitive respiration was obviously essential for the fermentative metabolism, because SHAM completely abolished growth of the mutant cells with both glucose or xylose as carbon source.     

Expression and effect of resistin on bovine and rat granulosa cell steroidogenesis and proliferation

Resistin, initially identified in adipose tissue and macrophages, was implicated in insulin resistance. Recently, its mRNA was found in hypothalamo-pituitary axis and rat testis, leading us to hypothesize that resistin may be expressed in ovary. In this study, we determined in rats and cows 1) the characterization of resistin in ovary by RT-PCR, immunoblotting, and immunohistochemistry and 2) the effects of recombinant resistin (10, 100, 333, and 667 ng/ml) ± IGF1 (76 ng/ml) on steroidogenesis, proliferation, and signaling pathways of granulosa cells (GC) measured by enzyme immunoassay, [(3)H]thymidine incorporation, and immunoblotting respectively. We observed that resistin mRNA and protein were present in several bovine and rat ovarian cells. Nevertheless, only bovine GC abundantly expressed resistin mRNA and protein. Resistin treatment decreased basal but not IGF1-induced progesterone (P<0.05; whatever the dose) and estradiol (P<0.005; for 10 and 333 ng/ml) production by bovine GC. In rats, resistin (10 ng/ml) increased basal and IGF1-induced progesterone secretion (P<0.0001), without effect on estradiol release. We found no effect of resistin on rat GC proliferation. Conversely, in cows, resistin increased basal proliferation (P<0.0001; for 100-667 ng/ml) and decreased IGF1-induced proliferation of GC (P<0.0001; for 10-333 ng/ml) associated with a decrease in cyclin D2 protein level (P<0.0001). Finally, resistin stimulated AKT and p38-MAPK phosphorylation in both species, ERK1/2-MAPK phosphorylation in rats and had the opposite effect on the AMPK pathway (P<0.05). In conclusion, our results show that resistin is expressed in rat and bovine ovaries. Furthermore, it can modulate GC functions in basal state or in response to IGF1 in vitro.