Sequential inoculum of <Emphasis Type="Italic">Hanseniaspora guilliermondii</Emphasis> and <Emphasis Type="Italic">Saccharomyces cerevisiae</Emphasis> for winemaking Campanino on an industrial scale

In this study, the effect of sequential inoculation with non-Saccharomyces (Hanseniaspora guilliermondii) and Saccharomyces cerevisiae yeast on the distinctive characteristics of the Campanino white wine was investigated. For this purpose, three independent winemaking experiments were carried out on an industrial scale (batches A, B and C). In detail, the first one was carried out using the sequential inoculation technique while the other two, using a S. cerevisiae single-strain starter or no inoculation representing the control batches. Microbiological and chemical parameters and sensorial profiles of the wines were defined. Interestingly, the results showed that when sequential cultures (H. guilliermondii in a sequential mixture with S. cerevisiae) were used, a better wine aroma and quality was observed. More specifically, the wine obtained by sequential inoculation showed lower acetic acid values and enhanced volatile profiles than the wine from the control batches. Finally, sensorial analysis confirmed that the sequential cultures led to an improvement in wine flavour. Therefore, results suggest that the sequential inoculation using non-Saccharomyces and Saccharomyces yeast represents a biotechnological practice that can improve the quality features of traditional white wine. It has been shown for the first time that on an industrial scale H. guilliermondii could be used in sequential inoculum with S. cerevisiae in making white Campanino wine.

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Qualitative Analysis of the Carbohydrate Composition of Apolipoprotein H

The specific binding of digoxigenin-labeled lectins to carbohydrate moieties is used to characterize the carbohydrate chains bound to apolipoprotein H. Our results show that apolipoprotein H is rich in sialic acid linked (2–6) to galactose or N-acetylgalactosamine. Sialic acid is not (2–3)-linked to galactose. Galactose is (1–4)-linked to N-acetylglucosamine and (1–3)-linked to N-acetylgalactosamine. High-mannose N-glycan chains are barely detectable. After N-glycosidase F treatment the molecular weight is substantially reduced. The main band is 32,500 daltons. Carbohydrate O-linked chains, which are mainly represented by sialic acid, are (2–6)-linked to galactose or N-acetylgalactosamine. Galactose is also organized in O-linked chains and it is (1–4)-linked to N-acetylglucosamine and (1–3)-linked to acetylgalactosamine. Biochemical analysis of carbohydrate structures reveals that no specific carbohydrate complex is bound to a single isoform.     

Hepatic respiratory compensation and haematological changes in the cave cyprinid, Phreatichthys andruzzii

In several ectotherms, including all members of the Osteichthyes studied so far, the spleen is capable of storing and releasing erythrocytes according to the animal's respiratory needs. The tropical cave cyprinid Phreatichthys andruzzii uses its liver rather than the spleen as the site of accumulation in the respiratory compensation process, like the amphibian Rana esculenta. The reversible process of erythrocyte accumulation in the liver is very evident in animals anaesthetized with chlorobutanol; MS-222, an anaesthetic widely used in lower vertebrates alters all the haematological parameters and is not suitable for studies on blood and respiration. The hepatic respiratory compensation mechanism is as efficient as the splenic one: in animals kept at 18 °C for 24 h the mean liver weight percentage was 70% higher than in specimens kept at 28 °C (2.43% of the body weight compared to 1.39%, in groups of six specimens) while mean red blood cell counts fell from 2.49 to 1.60 · 10¹² per l, in agreement with the haematocrit value and haemoglobin concentration; mean corpuscular volume remained constant (at about 177 fl). Accepted: 15 April 1997     

Fluorescent, internally quenched, peptides for exploring the pH-dependent substrate specificity of cathepsin B.

Cathepsin B is a cysteine protease that in tumor tissues is localized in both acidic lysosomes and extracellular spaces. It can catalyze the cleavage of peptide bonds by two mechanisms: endoproteolytic attack with a pH optimum around 7.4, and attack from the C-terminus with a pH optimum at 4.5-5.5. In this work, seven fluorescent, internally quenched, decapeptides have been synthesized using the prototypical cathepsin B selective substrate Z-Phe-Arg-AMC as a lead, and used to identify the structural factors determining the susceptibility of peptides to hydrolysis at acidic and neutral pH values. Each peptide differs from the others in one amino acid (residue 6) and contains a highly fluorescent Nma group linked to the alpha-amino function of the N-terminal Orn residue and a Dnp group linked to the side chain of the Lys(8) residue acting as a quencher. Proteolytic cleavage was monitored by measuring the increase of fluorescence at 440 nm upon excitation at 340 nm, and the cleavage sites were determined by HPLC followed by ESI-MS analysis. Peptides containing Ala or Phe at position 6 are good substrates for the enzyme at both pH 5.0 and 7.4. By contrast, those containing Glu, Asp, Lys or Val are not cleaved at all by cathepsin B at pH 7.4, and are poorly hydrolyzed at pH 5.0. These findings provide new information for the rational design of cathepsin B-activated peptide-containing anticancer drugs.     

Mesenchymal stromal cells from amniotic fluid are less prone to senescence compared to those obtained from bone marrow: An in vitro study

Mesenchymal stromal cells (MSCs) are considered to be an excellent source in regenerative medicine. They contain several cell subtypes, including multipotent stem cells. MSCs are of particular interest as they are currently being tested using cell and gene therapies for a number of human diseases. They represent a rare population in tissues; for this reason, they require, before being transplanted, an in vitro amplification. This process may induce replicative senescence, thus affecting differentiation and proliferative capacities. Increasing evidence suggests that MSCs from fetal tissues are significantly more plastic and grow faster than MSCs from bone marrow. Here, we compare amniotic fluid mesenchymal stromal cells (AF‐MSCs) and bone marrow mesenchymal stromal cells (BM‐MSCs) in terms of cell proliferation, surface markers, multidifferentiation potential, senescence, and DNA repair capacity. Our study shows that AF‐MSCs are less prone to senescence with respect to BM‐MSCs. Moreover, both cell models activate the same repair system after DNA damage, but AF‐MSCs are able to return to the basal condition more efficiently with respect to BM‐MSCs. Indeed, AF‐MSCs are better able to cope with genotoxic stress that may occur either during in vitro cultivation or following transplantation in patients. Our findings suggest that AF‐MSCs may represent a valid alternative to BM‐MSCs in regenerative medicine, and, of great relevance, the investigation of the mechanisms involved in DNA repair capacity of both AF‐MSCs and BM‐MSCs may pave the way to their rational use in the medical field.     

Stimulation of laccases from Trametes pubescens: Use in dye decolorization and cotton bleaching

The production of laccases from Trametes pubescens was investigated along with the role of nutrients and elicitors. Copper proved to be a fundamental inducer, although productivity yields were consistently enhanced only in the presence of additional compounds (textile dyes). Using a central composite design, the optimal culture condition was examined, by taking into consideration the three distinct variables and their combinatorial effect. The 290?U?ml^?1 of laccases were produced after setting nitrogen, copper, and reactive blue 19 concentration; in a bioreactor, activity recovery was lower (90?U?ml^?1) and pellet morphology was different. The activity of the laccase crude extract was maximal at 60°C and stable for 14?h at 50°C and for 2 months at pH 6 and room temperature. The biotechnological potential was assessed, confirming the capacity to decolorize single or mixed solutions of textile dyes and to enhance the whitening yield of raw cotton fibers, working in synergism with the conventional H₂O₂-based method.     

Occurrence, diversity, and pathogenicity of halophilic Vibrio spp. and non-O1 Vibrio cholerae from estuarine waters along the Italian Adriatic coast.

The occurrence, diversity, and pathogenicity of Vibrio spp. were investigated in two estuaries along the Italian Adriatic coast. Vibrio alginolyticus was the predominant species, followed by Vibrio parahaemolyticus, non-O1 Vibrio cholerae, and Vibrio vulnificus. By using a biochemical fingerprinting method, all isolates were grouped into nine phenotypes with similarity levels of 75 to 97.5%. The production of toxins capable of causing cytoskeleton-dependent changes was detected in a large number of Vibrio strains. These findings indicate a significant presence of potentially pathogenic Vibrio strains along the Adriatic coast.     

Separation and purification of periplasmic cytochrome c553 using reversed micelles

Surfactant concentration, ionic strength, and pH were optimised for the selective separation and purification of periplasmic cytochrome c553 from recombinant E. coli TG2 cells using response surface methodology. Back-extraction was accomplished using counter-ionic surfactant addition. Optimum forward extraction conditions were: 65 mM bis(2-ethylhexyl)sulfosuccinate sodium salt (AOT), 0.07 M NaCl, and pH 8.4, while the optimum back-extraction conditions were 80 mM trioctylmethylammonium chloride, 0.85 M KCl, and pH 9.62. In comparison to a conventionally purified sample using column chromatography (10 mg cytochrome c553 l–1 with a purity of 0.66), reverse micelles achieved the same concentration and similar purity (0.50) in only two simple steps.