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BACKGROUND Knowledge regarding microaerophilic and anaerobic specific spoilage organisms (SSOs) is crucial for an appropriate evaluation of vacuum-packed ham. The objective of this study was to characterize the SSO community in vacuum-packed ham by a culture-dependent technique and MiSeq next-generation sequencing (NGS) platform. The relation between changes among the SSO group in the ham and changes in sensory characteristics of the product was also assessed. RESULTS In the study, conventional microbiological analyses were employed in order to establish the participation of several groups of microorganisms in the deterioration of vacuum-packed ham. The diversity of the SSO group in the product was further assessed with the use of MiSeq NGS technology. The bacteria identified in sliced cooked ham belonged mostly to four phyla, namely Actinobacteria, Proteobacteria, Firmicutes and Bacteroidetes. A temperature of 4 °C favoured the development of mesophilic and psychrophilic/psychrotrophic flora, mainly Lactobacillaceae, Enterobacteriaceae and Micrococcaceae families. A high ratio of Brochothrix thermosphacta species and new, cold-tolerant Clostridium spp. was also observed. The growth of these microorganisms facilitated changes in the pH value and organoleptic characteristics of the product. CONCLUSION This study confirms that the combination of culturing and MiSeq NGS technology improves the microbial evaluation of food. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this study, the treatment of wastewater with a high nitrate content was investigated using the method of cryoconcentration on a pilot scale. The initial nitrate concentration in the treated wastewater was at 1,500 mg N/l. During 40 h of cryoconcentration of the wastewater, 176.6 kg of ice was produced, corresponding to a total process efficiency of 4.42 kg/h of ice. The crystallization temperature decreased from −0.5 to −9°C during the process. The final concentration of nitrates in the concentrated product was at 37 g N/l, and the conductivity was at 158 mS/cm. The conductivity of the water obtained by melting the ice ranged from 0.98 to 1.4 mS/cm. Concentrates with initial nitrate concentrations of 3, 6, and 9 g N/l were then subjected to microbial denitrification. The values of the specific nitrate reduction rates ranged from 43.1 to 49 mg N/gVSS h. [ABSTRACT FROM PUBLISHER]

The aim of the study was to optimize a saline brine denitrification by halophilic microorganisms Haloferax mediterranei. To define the optimum parameters of the process, the Latin square method was used (Statistica 6.0). The highest specific nitrate reduction rate was observed at a temperature of 37 °C and pH 7.0. There was no significant effect of NaCl on nitrate ion reduction at the concentration range from 2.5 to 3.5 M. During brine denitrification in a batch bioreactor the rates of specific nitrate reduction and nitrate reduction reached 100.5 mg N-NO3- per 1 gram of dry mass during 24 h and 135 mg N-NO3/dm3·day, respectively. [ABSTRACT FROM AUTHOR]

Metabolites of polychlorinated biphenyls (PCBs)—hydroxylated PCBs (OH-PCBs), chlorobenzyl alcohols (CB-OHs), and chlorobenzaldehydes (CB-CHOs)—were incubated in vitro with the extracellular liquid of Pleurotus ostreatus, which contains mainly laccase and low manganese-dependent peroxidase (MnP) activity. The enzymes were able to decrease the amount of most of the tested OH-PCBs by > 80% within 1 h; the removal of more recalcitrant OH-PCBs was greatly enhanced by the addition of the laccase mediator syringaldehyde. Conversely, glutathione substantially hindered the reaction, suggesting that it acted as a laccase inhibitor. Hydroxylated dibenzofuran and chlorobenzoic acid were identified as transformation products of OH-PCBs. The extracellular enzymes also oxidized the CB-OHs to the corresponding CB-CHOs on the order of hours to days; however, the mediated and nonmediated setups exhibited only slight differences, and the participating enzymes could not be determined. When CB-CHOs were used as the substrates, only partial transformation was observed. In an additional experiment, the extracellular liquid of Irpex lacteus, which contains predominantly MnP, was able to efficiently transform CB-CHOs with the aid of glutathione; mono- and di-chloroacetophenones were detected as transformation products. These results demonstrate that extracellular enzymes of ligninolytic fungi can act on a wide range of PCB metabolites, emphasizing their potential for bioremediation. [ABSTRACT FROM AUTHOR]

We studied the effects of a hydrophobized reversed-phase feed adsorbent in the form of a polyoctylated polysilicate hydrogel (POPSH) on productivity indicators, metabolic adaptation, and on the level of polychlorinated biphenyls (PCBs) in the blood of growing Holsteinized black-and-white heifers during the transition period. Two groups of two-month-old heifers of 20 head each were used. The experimental group received POPSH in addition to the main diet. The use of the adsorbent led to an increase in daily weight gain by 19.9% and to a decrease in the total concentration of PCB congeners found in whole blood by 40%. The greatest decrease in concentration (35–52%) was observed for tetra-, penta- and hexachlorobiphenyls. These results demonstrate the possibilities of effective protection of calves from lipophilic toxins of feed and their active decontamination. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs), 33 methylated PAHs (Me-PAHs), and 14 nitrated PAHs (NPAHs) were measured in wastewater treatment plants (WWTPs) to study the removal efficiency of these compounds through the WWTPs, as well as their source appointment and potential risk in the effluent. The concentrations of ∑PAHs, ∑Me-PAHs, and ∑NPAHs were 2.01–8.91, 23.0–102, and 6.21–171 µg/L in the influent, and 0.17–1.37, 0.06–0.41 and 0.01–2.41 µg/L in the effluent, respectively. Simple Treat 4.0 and meta-regression methods were applied to calculate the removal efficiencies (REs) for the 63 PAHs and their derivatives in 10 WWTPs and the results were compared with the monitoring data. Overall, the ranges of REs were 55.3–95.4% predicated by the Simple Treat and 47.5–97.7% by the meta-regression. The results by diagnostic ratios and principal component analysis PCA showed that "mixed source" biomass, coal composition, and petroleum could be recognized to either petrogenic or pyrogenic sources. The risk assessment of the effluent was also evaluated, indicating that seven carcinogenic PAHs, Benzo[a]pyrene, Dibenz[a,h]anthracene, and Benzo(a)anthracene were major contributors to the toxics equivalency concentrations (TEQs) in the effluent of WWTPs, to which attention should be paid. [ABSTRACT FROM AUTHOR]