In situ tests for water quality assessment: a case study in Pampean rivers

Two invertebrate species (Hyalella curvispina and Palaemonetes argentinus) and one macrophyte (Egeria densa) from a naturally high nutrient content system (Pampean rivers of La Plata, Argentina) were evaluated for their potential use in situ assays aiming to assess changes in water quality. Invertebrates were individually placed in cylindrical chambers in polluted sections of rivers and in reference upstream sites. Mortality after 48 h was high in polluted and reduced in control sites. Mortality was also higher in situ assays than in laboratory static tests. Standard sections of the macrophyte were also deployed at the reference and control sites. Growth (7 days) in terms of mass increment (but not in length) was consistently reduced in polluted sites. Results of benthic invertebrate and periphitic algae surveys were consistent with the in situ tests: pollution resulted in a decrease in the number of taxa, taxa replacement and in changes in the value of the biotic indices Indice Biótico PAMPeano and Indice de Diatomeas Pampeano, indicating deterioration of water quality. In situ assays have a high potential as environmental tools in integrated approaches of bioassessment programs.     

Performance of Cinta Senese pigs and their crosses with Large White 2. Physical, chemical and technological traits of Tuscan dry-cured ham

Technological, chemical and physical traits of cured ham from Cinta Senese and Large White pigs, and their crosses were investigated. Hams were obtained from 29 Cinta Senese (CS), 29 Large White × Cinta Senese (LW × CS) and 12 Large White (LW) pigs, fed a commercial mixture. Sensory and chemical–physical analysis was performed on a sample-slice and on muscles (Biceps femoris – BF; Semimembranosus – SM; Semitendinosus – ST) and subcutaneous fat. CS showed the highest trimming loss and the lowest salting loss. Hams of CS pigs scored higher for fatness than those of LW pigs, LW × CS showing intermediate values. On sample-slice, CS exhibited higher firmness, redness and marbling of lean, and greater fat extension than LW, with crosses having intermediate scores. Muscle moisture was lowest in CS, while both SM and BF from LW had the highest percentage of protein and the lowest of ash. CS showed higher intramuscular fat content than LW × CS and LW. Shear force of BF was higher in CS than in LW × CS and LW. With respect to LW, CS had lower values of L^* in muscles, and higher values of a^* in subcutaneous fat. Subcutaneous fat of CS contained less SFA and more MUFA than LW × CS and LW.     

Effect of flaxseed oil in diet on fatty acid composition in the liver of Nile tilapia (Oreochromis niloticus)

This study analyzed the effects of different concentrations of flaxseed oil (FO) on the proximate composition and the contents of alpha-linolenic acid (LNA, 18:3n-3), eicosapentaenoic (EPA, 20:5n-3), and docosahexaenoic (DHA, 22:6n-3) fatty acids in the liver of cultured Nile tilapia (Oreochromis niloticus). During the five-month culture period, tilapias were given diets with incremental concentrations of FO (0.00%; 1.25%; 2.50%; 3.75%, and 5.00%) as a replacement of sunflower oil (control). There was no significant difference in moisture and ash content in the liver between treatments. Protein values ranged from 12.1% (treatment II) to 13.9% (treatment V) and total lipids ranged from 5.6% (treatment V) to 7.2% (treatment II). There was no significant difference between most treatments. Fatty acid methyl esters (FAMEs) were quantitatively analyzed by capillary gas chromatography against a C(23:0), internal standard. Variations in concentrations (in mg g(-1) of total lipids) of fatty acids between treatment I and treatment V ranged from 4.2 to 51.2 (LNA), from 0.2 to 2.3 (EPA), and from 10.6 to 56.2 (DHA), respectively. This experiment demonstrated that increasing amounts of LNA in feed may markedly increase the amounts of LNA, EPA, and DHA in the liver of Nile tilapia.     

Bacteria of Lactobacillus casei group: characterization, viability as probiotic in food products and their importance for human health

Lactobacillus casei is a group of phenotypically and genetically heterogeneous lactic acid bacteria, able to colonize various natural and man-made environments. Strains of the Lactobacillus casei group have been widely studied with respect to their health-promoting properties. Several beneficial functions for the human organism have been attributed to regular consumption of food products containing these strains. Bacteria of the Lactobacillus casei group are of great interest for the food industry to improve food quality. A number of studies have been conducted in order to evaluate the viability of strains of Lactobacillus casei group as probiotic in dairy products, desserts, among others food products. Despite its importance for the food industry, the taxonomy of the Lactobacillus casei group is still unclear. This review discusses important studies related to characterization of strains of Lactobacillus casei group, the application of these bacteria as probiotic in different food products and the main beneficial effects attributed to regular consumption of products containing such microorganisms.     

Biogeochemistry of metalliferous peats: sulfur speciation and depth distributions of dsrAB genes and Cd, Fe, Mn, S, and Zn in soil cores

Spatial relationships between concentrations of Cd, Fe, Mn, S, and Zn and bacterial genes for dissimilatory sulfate reduction were studied in soils of the Manning peatland region in western New York. Peat cores were collected within a field exhibiting areas of Zn phytotoxicity, and pH and elemental concentrations were determined with depth. The oxidation states of S were estimated using S-XANES spectroscopy. Soil microbial community DNA was extracted from peat soils for ribosomal RNA intergenic spacer analysis (RISA) of diversity profiles with depth. To assess the presence of sulfate-reducing microorganisms (SRM), DNA extracts were also used as templates for PCR detection of dsrAB genes coding for dissimilatory (bi)-sulfite reductase. Elemental distributions, S redox speciation, and detection of dsrAB genes varied with depth and water content. The pH of peat soils increased with depth. The highest concentrations of Zn, Cd, and S occurred at intermediate depths, whereas Mn concentrations were highest in the topmost peat layers. Iron showed a relatively uniform distribution with depth. Concentrations of redox sensitive elements, S and Mn, but not Fe, seemed to respond to variations in water content and indicated vertical redox stratification in peat cores where topmost peats were typically acidic and oxidizing and deeper peats were typically circumneutral and reducing. Even then, S-XANES analyses showed that surface peats contained >50% of the total S in reduced forms while deep peats contained generally <5% of the total S in oxidized forms. While bacterial RISA profiles of the peats were diverse, dsrAB gene detection followed redox stratification chemistry closely. For the most part, dsrAB genes were detected in deeper peats, where S accumulation was evident, while they were not detected in topmost peat layers where Mn accumulation indicated oxic conditions. Combined chemical, spectroscopic, and microbiological analyses indicated that prolonged exposure to dry-wet cycles resulted in the formation of two redox-stratified zones with distinct chemical and microbiological signatures within peat cores of the Manning peatland region. As illustrated in this study, changes in redox conditions affect bacterial community composition and downward mobility of toxic elements, which has implications for water contamination and the design of metal remediation strategies.     

Abatement of the inhibitory effect of chloride anions on the photo-Fenton process

The inhibition of the photo-Fenton (Fe2+/Fe3+, H2O2, UV light) degradation of synthetic phenol wastewater solutions by chloride ions is shown to affect primarily the photochemical step of the process, having only a slight effect on the thermal or Fenton step. Kinetic studies of the reactions of oxoiron (IV) (FeO2+) with phenol indicate that, if FeO2+ is formed in the photo-Fenton degradation, its role is probably minor. Finally, it is shown that, for both a synthetic phenol wastewater and an aqueous extract of Brazilian gasoline, the inhibition of the photo-Fenton degradation of the organic material in the presence of chloride ion can be circumvented by maintaining the pH of the medium at or slightly above 3 throughout the process, even in the presence of significant amounts of added chloride ion (0.5 M).     

Intramammary inoculation of Panax ginseng extract in cows at drying off enhances early mammary involution

This study was designed to evaluate the effects of a single intramammary infusion of Panax ginseng extract on cell proliferation and death mechanism in bovine mammary gland during early involution. Eight mammary quarters from six non-pregnant cows in late lactation were infused with 10 ml of ginseng solution (3 mg/ml), six quarters were treated with 10 ml of placebo (vehicle alone) and six quarters were maintained as uninoculated controls. Milking was interrupted after infusion. Animals included in the three groups were slaughtered 7 d after inoculation and samples for histological analysis were taken. Morphometric analysis showed a significant increase in percentages of mammary tissue area occupied by stroma in ginseng-treated quarters compared with controls. A significant increase of immunostained area for bax protein and active caspase-3 was observed in ginseng-treated quarters compared with controls, whereas no differences were observed for bcl-2 immunostaining. Expression of bax mRNA was significantly higher in ginseng-treated quarters than in controls. The bax/bcl-2 ratio indicated a significant predominance of bax over bcl-2 mRNA expression in ginseng-treated quarters compared with controls. The rise of epithelial and stromal cell apoptosis in situ by TUNEL was more marked in quarters treated with ginseng than in controls. Ginseng inoculation had no effect on the number of epithelial and stromal proliferating cells labelled with Ki-67 antibody. Ratio of apoptotic to proliferating cells was higher in quarters treated with ginseng compared with controls, indicating a net loss of cells in parenchymal components. Also, the intramammary inoculation of ginseng extract at drying off increased the rate of mammary cell apoptosis without inhibiting cell proliferation. Taken together, these changes are indicative of mammary regression enhancement during early involution.     

Compositional and quantitative microtextural characterization of historic paintings by micro-X-ray diffraction and Raman microscopy

This work shows the benefits of characterizing historic paintings via compositional and microtextural data from micro-X-ray diffraction (μ-XRD) combined with molecular information acquired with Raman microscopy (RM) along depth profiles in paint stratigraphies. The novel approach was applied to identify inorganic and organic components from paintings placed at the 14th century Islamic University-Madrasah Yusufiyya-in Granada (Spain), the only Islamic University still standing from the time of Al-Andalus (Islamic Spain). The use of μ-XRD to obtain quantitative microtextural information of crystalline phases provided by two-dimensional diffraction patterns to recognize pigments nature and manufacture, and decay processes in complex paint cross sections, has not been reported yet. A simple Nasrid (14th century) palette made of gypsum, vermilion, and azurite mixed with glue was identified in polychromed stuccos. Here also a Christian intervention was found via the use of smalt, barite, hematite, Brunswick green and gold; oil was the binding media employed. On mural paintings and wood ceilings, more complex palettes dated to the 19th century were found, made of gypsum, anhydrite, barite, dolomite, calcite, lead white, hematite, minium, synthetic ultramarine blue, and black carbon. The identified binders were glue, egg yolk, and oil.     

Assessment of the effect of the non-volatile wine matrix on the volatility of typical wine aroma compounds by headspace solid phase microextraction/gas chromatography analysis

BACKGROUND: The aim of this study was to evaluate the effect of the whole non‐volatile wine matrix composition on the volatility of typical wine aroma compounds by comparing the slopes of regression lines of five deodorised and reconstituted wines with the slopes calculated for the same compounds in a control wine with no matrix effect. RESULTS: The main effect observed was a reduction in the slopes, or a retention effect, that was largest for the reconstituted sparkling wine, which showed between 11 and 69% lower slopes than the control wine. In addition, an increase in the slopes, or a ‘salting‐out’ effect, in the most compositionally complex reconstituted aged‐red and sweet wines was also noticed for some volatiles with a very low boiling point or a low hydrophobic constant value. CONCLUSION: This study has shown that the non‐volatile composition of wines strongly affects the volatility of wine aroma compounds. In addition, the aroma chemical class, in particular its physicochemical properties (volatility and hydrophobicity), strongly influences this behaviour. On the basis of these results, many odour threshold values calculated in simple hydroalcoholic solutions and usually employed to evaluate the odour importance of specific volatile compounds may have been over‐ or underestimated. Copyright © 2011 Society of Chemical Industry