Combined effect of starter culture and temperature on phenolic compounds during fermentation of Taggiasca black olives.

The influence of two operative parameters on the fermentation process of table olives from Taggiasca cultivar were investigated. Laboratory scale fermentations were performed using Lactobacillus plantarum as the only starter and in combination with Saccharomyces cerevisiae at three different temperatures (23, 30 and 37°C). Control tests used for each trial were fermented only by indigenous microflora. pH and phenolic compounds were monitored in the brine and olive flesh during the fermentation. Higher temperatures (37°C) enhanced notably the release of phenolic compounds in the brine. High performance liquid chromatography (HPLC) analysis of brines evidenced the complete hydrolysis of oleuropein after 100 days of fermentation at 37°C for all treatments. The antioxidant power of the extracts was linearly correlated to their polyphenol contents. The results confirmed the efficiency of treatments compared with the control tests for debittering process of table black olives. Phenolic compounds in the brines can be then extracted and used in food, cosmetic and pharmaceutical industries.

Fragmentation of human erythrocyte actin following exposure to hypoxia.

In a comparative study on erythrocytes (RBCs) drawn from mountaineers before and after a high-altitude stay, we observed that upon returning to sea level, their RBCs displayed a senescent-like phenotype as indicated by their density and the partial loss of membrane proteins which are shed by ageing RBCs. The aim of this study was to investigate possible changes in the membrane skeleton of these RBCs and to compare them with pathological RBCs. We analysed the proteins of RBC ghosts obtained from our subjects before and after returning to sea level by two-dimensional electrophoresis and mass spectrometry. We observed lower expression and fragmentation of beta-actin after exposure to hypoxia. This suggested an alteration in membrane skeleton structure, which was confirmed by beta-actin release in cell lysates during ghost preparation. We observed a similar actin fragmentation and release in RBC lysates from beta-thalassaemic patients. In conclusion, these results indicate that after exposure to hypoxia, RBCs display a modification of their actin and cytoskeleton instability.

Interdisciplinary study for the evaluation of biochemical alterations on mussel Mytilus galloprovincialis exposed to a tributyltin-polluted area.

An interdisciplinary approach was employed to monitor the concentration and the effects of butyltin compounds in mussels (Mytilus galloprovincialis). Tissues from animals exposed to a marine area (Vado Ligure harbour) with a high concentration of tributyltin (TBT) were analysed and compared with control samples. TBT concentrations were measured by gas chromatography-mass spectrometry and the protein pattern in gill tissues was studied by proteomic analysis. Several proteomic signatures associated with contaminant exposure were observed; spots that were significantly increased in all contaminated samples were identified by mass spectrometry as fragments of ß-tubulin. The degradation of ß-tubulin was then confirmed by western blot analysis with specific anti-ß-tubulin antibody. The effects observed on mussel gills after exposure in the TBT-polluted area are discussed.

Integrated analytical approach in veal calves administered the anabolic androgenic steroids boldenone and boldione: urine and plasma kinetic profile and changes in plasma protein expression.

Surveillance of illegal use of steroids hormones in cattle breeding is a key issue to preserve human health. To this purpose, an integrated approach has been developed for the analysis of plasma and urine from calves treated orally with a single dose of a combination of the androgenic steroids boldenone and boldione. A quantitative estimation of steroid hormones was obtained by LC-APCI-Q-MS/MS analysis of plasma and urine samples obtained at various times up to 36 and 24 h after treatment, respectively. These experiments demonstrated that boldione was never found, while boldenone alpha- and beta-epimers were detected in plasma and urine only within 2 and 24 h after drug administration, respectively. Parallel proteomic analysis of plasma samples was obtained by combined 2-DE, MALDI-TOF-MS and muLC-ESI-IT-MS/MS procedures. A specific protein, poorly represented in normal plasma samples collected before treatment, was found upregulated even 36 h after hormone treatment. Extensive mass mapping experiments proved this component as an N-terminal truncated form of apolipoprotein A1 (ApoA1), a protein involved in cholesterol transport. The expression profile of ApoA1 analysed by Western blot analysis confirmed a significant and time dependent increase of this ApoA1 fragment. Then, provided that further experiments performed with a growth-promoting schedule will confirm these preliminary findings, truncated ApoA1 may be proposed as a candidate biomarker for steroid boldenone and possibly other anabolic androgens misuse in cattle veal calves, when no traces of hormones are detectable in plasma or urine.

Steric factors controlling the surface hybridization of PCR amplified sequences.

This study elucidated the hybridization behavior of surface-bound oligonucleotides to their longer PCR-amplified targets. The screen-printed gold surface of disposable electrodes was the platform onto which thiol-tethered oligonucleotides (21-mer) were immobilized by chemisorption. As a model case, approximately 600-bp amplicons were studied. Surface hybridization was monitored by means of an enzyme-linked assay with electrochemical detection. Use of different surface-tethered probe sequences over a wide range of surface densities was explored to achieve the highest duplex yield. Both the surface coverage by the probe and its relative position on the target strand were found to control the efficiency of capture of the target sequence. Interfacial hybridization occurred with the highest efficiency for a probe coverage of approximately 2.9 x 10(12) molecules/cm2 and when the 3' end of the amplicon was involved. An unusual (bell-shaped) response/amplicon concentration profile was additionally found. It was hypothesised that when the amount of solution-phase target is relatively high, random collisions make reannealing of the approximately 600-bp strands favored over formation of the surface-tethered probe-amplicon complex. This paper also describes a strategy to enhance the sensitivity of enzyme-linked hybridization assays. Such a strategy relies on formation, around the long target sequence, of dendritic-like structures, which could offer multiple anchoring points for the enzyme conjugate. The results shown in this work might have great significance for the practical application of hybridization to oligonucleotide chips.