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Abstract: The objective of this work was to study the entrapped conditions of activated carbon in calcium-alginate beads for the clarification of winery wastewaters. An incomplete 33 factorial design was carried out to study the efficiency of activated carbon (0.5–2%); sodium alginate (1–5%); and calcium chloride (0.050–0.900M), on the following dependent variables: colour reduction at 280, 465, 530 and 665nm. The activated carbon and calcium chloride were the most influential variables in the colour reduction. Nearly 100% colour reductions were found for the wavelengths assayed when employing 2% of activated carbon, 5% of sodium alginate and intermediate concentrations of calcium chloride (0.475M). Instead, other conditions like, 2% of activated carbon, 4% of sodium alginate and 0.580M of calcium chloride can also give absorbance reductions close to 100%. [Copyright &y& Elsevier]

Abstract: This work proposes the utilization of trimming vine shoots hydrolyzates by Lactobacillus pentosus for lactic acid employing continuous culture and the evaluation of biosurfactants production. The treatment of hydrolyzates with sulphuric acid (prehydrolysis) allowed the solubilization of hemicelluloses to give liquors containing 18g/L of xylose, 11.1g/L of glucose, 4.3g/L of arabinose and 4g/L of acetic acid. Continuous fermentation of hemicellulosic hydrolyzates gave a Q P =3.10g of lactic acid/Lh and Y P/S =0.70g of lactic acid/g of sugars for a dilution rate of 0.02h−1 using 10g/L of corn steep liquor and 10g/L of yeast extract as nutrients. When nutrients were replaced by 20g/L of distilled lees from white wine production the same results were obtained without interfering, lees, in the lactic acid recovery from the fermentation medium. On the other hand, L. pentosus cells were submitted to extraction process with PBS to evaluate the intracellular biosurfactants. In presence of vinification lees or corn steep liquid plus yeast extract, the extracted biosurfactants of L. pentosus reduced the superficial tension of PBS in 23.5 and 25.5mN/m, respectively. No extracellular biosurfactants were observed. [Copyright &y& Elsevier]

Preterm infants in a neonatal intensive care unit (NICU) are exposed to multidrug-resistant bacteria previously adapted to the hospital environment. The aim of the present study was to characterize the bacterial antibiotic-resistant high-risk lineages colonizing preterm infants during their NICU stay and their persistence in faeces after 2 years. A total of 26 preterm neonates were recruited between October 2009 and June 2010 and provided 144 faecal samples. Milk samples (86 mother's milk, 35 human donor milk and 15 formula milk) were collected at the same time as faecal samples. An additional faecal sample was recovered in 16 infants at the age of 2 years. Samples were plated onto different selective media, and one colony per morphology was selected. Isolates were identified by 16S rDNA nucleotide sequence and MALDI-TOF. Antibiotic susceptibility (agar dilution), genetic diversity (RAPD, PFGE and MLST) and virulence factors (only in enterococcal and staphylococcal isolates) were determined by PCR. A high proportion of antibiotic-resistant high-risk clones was detected in both faecal and milk samples during the NICU admittance. Almost all infants were colonized by Enterococcus faecalis ST64 and Enterococcus faecium ST18 clones, while a wider genetic diversity was observed for the Gram-negative isolates. Multidrug-resistant high-risk clones were not recovered from the faecal samples of the 2-year-olds. In conclusion, the gut of preterm infants admitted to the NICU might be initially colonized by antibiotic-resistant and virulent high-risk lineages, which are later replaced by antibiotic-susceptible community ones. [ABSTRACT FROM AUTHOR]