Selected Schizosaccharomyces pombe Strains Have Characteristics That Are Beneficial for Winemaking

At present, wine is generally produced using Saccharomyces yeast followed by Oenococus bacteria to complete malolactic fermentation. This method has some unsolved problems, such as the management of highly acidic musts and the production of potentially toxic products including biogenic amines and ethyl carbamate. Here we explore the potential of the fission yeast Schizosaccharomyces pombe to solve these problems. We characterise an extensive worldwide collection of S. pombe strains according to classic biochemical parameters of oenological interest. We identify three genetically different S. pombe strains that appear suitable for winemaking. These strains compare favourably to standard Saccharomyces cerevisiae winemaking strains, in that they perform effective malic acid deacidification and significantly reduce levels of biogenic amines and ethyl carbamate precursors without the need for any secondary bacterial malolactic fermentation. These findings indicate that the use of certain S. pombe strains could be advantageous for winemaking in regions where malic acid is problematic, and these strains also show superior performance with respect to food safety

Amino acids and biogenic amines in red varietal wines: the role of grape variety, malolactic fermentation and vintage

This work studies for the first time the amino acid and biogenic amine composition of Rioja red wines made with the red minority varieties Vitis vinífera cv. Monastel and Maturana Tinta de Navarrete, using Tempranillo as a reference variety. The role of malolactic fermentation and vintage on these compounds was also analysed, and discriminate analyses were applied to achieve a possible differentiation of the wines. Amino acid composition allowed a differentiation of wines according to grape variety. Monastel was characterised by the highest value in -alanine and Maturana Tinta de Navarrete by its highest value in OH-proline. However, biogenic amines were no able to classify varietal wines. The malolactic fermentation had significant changes on the amino acid and biogenic amine content, and allowed distinguishing wines that underwent this process from wines without malolactic fermentation. No correlation was found between total amino acids and total biogenic amines after malolactic fermentation, suggesting that a higher initial concentration of amino acids in the medium did no affect the concentration of biogenic amines after malolactic fermentation. Vintage influenced the amino acid and biogenic amine pattern, obtaining a clear separation of wines by vintages. Monastel and Maturana Tinta de Navarrete wines showed a minor varietal character and were more influenced by the climatic conditions of each vintage than Tempranillo wines. All the wines showed histamine levels below the human physiological threshold and implemented regulations. © 2013 Springer-Verlag Berlin Heidelberg

Ultra-Performance Liquid Chromatography-Triple Quadruple Mass Spectrometry (UPLC-TQ/MS) for Evaluation of Biogenic Amines in Wine

In this study, a fast, simple, and sensitive analytical method for direct determination of biogenic amines tryptamine, putrescine, histamine, phenylethylamine, tyramine, cadaverine, spermine, and spermidine in wine has been developed and validated. Detection of analytes was performed with ultra-performance liquid chromatography (UPLC) coupled to triple quadruple mass spectrometer (TQ/MS). The calibration curves of all amines were linear with correlation coefficients (R2) ranging from 0.9906 for putrescine to 0.9998 for histamine and 2-phenyethylamine. The accuracy of the method was checked with a standard addition method, showing good accuracy, repeatability, and reproducibility (RSD < 10%). The limit of detection (LOD) and limit of quantification (LOQ) ranged from 0.50 to 30 μg/L and 1.50 to 90 μg/L, respectively, for all amines. The validated method was applied to detect and quantify biogenic amines in Macedonian red and white wines. Higher concentration of amines was observed in red wines (5797 μg/L, on average) compared to the white wines (1485 μg/L, on average)

Bacteria-Affecting Cephalopods

16 pages, 6 figures, 2 tables.-- This chapter is licensed under the terms of the Creative Commons Attribution 4.0 International LicenseBacterial pathogens contribute to obtain an unsuccessful production of cephalopods. An updated overview of the knowledge of these pathogens must be a valuable tool to improve their aquarium maintenance and aquaculture. The present work provides a description of the main bacterial pathogens associated with larval stages of cultured Octopus vulgaris, and juvenile and adults of several cephalopods. Vibrio species, reported with ability to cause vibriosis in aquaculture, are the main bacteria associated with skin lesions in adults. Different species of Pseudomonas and Aeromonas, among others, have also been detected. Furthermore, gram-positive bacteria such as Bacillus have been also described. Among them, V. alginolyticus, V. carchariae, V. parahaemolyticus, V. splendidus and V. lentus have also been isolated from sterile organs or fluids of animals and their potential as invaders proved. However, only V. alginolyticus or V. lentus has the ability to cause lesions, and, in addition, the last one is proved as the causative agent of death in octopuses. Other organs such as eyes of squids are also colonized by Vibrio species or Micrococcus sp., and recently Photobacterium swingsii and Lactococcus garvieae have been reported associated with a retrobulbar lesion in octopus. Rickettsial-like organisms (RLO) are also detected in the gills of the octopus, having a detrimental effect on the respiratory gaseous exchange of the animals. Cultures of octopus paralarvae show a genetically diverse community comparable to those reported previously from other marine hatcheries. Bacteria included in the Splendidus clade is the dominant group in all conditions, except in one of them, where V. alginolyticus, V. proteolyticus or Pseudomonas fluorescens are the main detected groups. Furthermore, Shewanella or Pseudoalteromonas undina have also been identified. All this shows that pathogenic bacteria are frequent microorganisms associated with aquarium maintenance and culture of cephalopods, and special attention on maintaining a well-balanced community of microorganisms should be appliedPeer reviewe