141 research outputs found
Limosilactobacillus balticus sp. nov., Limosilactobacillus agrestis sp. nov., Limosilactobacillus albertensis sp. nov., Limosilactobacillus rudii sp. nov. and Limosilactobacillus fastidiosus sp. nov., five novel Limosilactobacillus species isolated from the vertebrate gastrointestinal tract, and proposal of six subspecies of Limosilactobacillus reuteri adapted to the gastrointestinal tract of specific vertebrate hosts
Ten strains, BG-AF3-A(T), pH52_RY, WF-MT5-A(T), BG-MG3-A, Lr3000(T), RRLNB_1_1, STM3_1(T), STM2_1, WF-MO7-1(T) and WF-MA3-C, were isolated from intestinal or faecal samples of rodents, pheasant and primate. 16S rRNA gene analysis identified them as Limosilactobacillus reuteri. However, average nucleotide identity and digital DNA-DNA hybridization values based on whole genomes were below 95 and 70%, respectively, and thus below the threshold levels for bacterial species delineation. Based on genomic, chemotaxonomic and morphological analyses, we propose five novel species with the names Limosilactobacillus balticus sp. nov. (type strain BG-AF3-A(T)=DSM 110574(T)=LMG 31633(T)), Limosilactobacillus agrestis sp. nov. (type strain WF-MT5-A(T)=DSM 110569(T)=LMG 31629(T)), Limosilactobacillus albertensis sp. nov. (type strain Lr3000(T)=DSM 110573(T)=LMG 31632(T)), Limosilactobacillus rudii sp. nov. (type strain STM3_1(T)=DSM 110572(T)=LMG 31631(T)) and Limosilactobacillus fastidiosus sp. nov. (type strain WF-MO7-1(T)=DSM 110576(T)=LMG 31630(T)). Core genome phylogeny and experimental evidence of host adaptation of strains of L. reuteri further provide a strong rationale to consider a number of distinct lineages within this species as subspecies. Here we propose six subspecies of L. reuteri: L. reuteri subsp. kinnaridis subsp. nov. (type strain AP3(T)=DSM 110703(T)=LMG 31724(T)), L. reuteri subsp. porcinus subsp. nov. (type strain 3c6(T)=DSM 110571(T)=LMG 31635(T)), L. reuteri subsp. murium subsp. nov. (type strain lpuph1(T)=DSM 110570(T)=LMG 31634(T)), L. reuteri subsp. reuteri subsp. nov. (type strain F 275(T)=DSM 20016(T)=ATCC 23272(T)), L. reuteri subsp. suis subsp. nov. (type strain 1063(T)=ATCC 53608(T)=LMG 31752(T)) and L. reuteri subsp. rodentium subsp. nov. (type strain 100-23(T)=DSM 17509(T)=CIP 109821(T))
Galacto-Oligosaccharides : production, properties, applications, and significance as prebiotics
Galacto-oligosaccharides (GOS) have now been definitely established as prebiotic ingredients after in vitro and
animal and human in vivo studies. Currently, GOS are produced by glycoside hydrolases (GH) using lactose as substrate.
Converting lactose into GOS by GH results in mixtures containing GOS of different degrees of polymerization (DP),
unreacted lactose, and monomeric sugars (glucose and galactose). Recent and future developments in the production
of GOS aim at delivering purer and more efficient mixtures. To produce high-GOS-content mixtures, GH should not
only have good ability to catalyze the transgalactosylation reaction relative to hydrolysis, but also have low affinity for
the GOS formed relative to the affinity for lactose. In this article, several microbial GH, proposed for the synthesis of
GOS, are hierarchized according to the referred performance indicators. In addition, strategies for process improvement
are discussed. Besides the differences in purity of GOS mixtures, differences in the position of the glycosidic linkages
occur, because different enzymes have different regiochemical selectivity. Depending on oligosaccharide composition,
GOS products will vary in terms of prebiotic activity, as well as other physiological effects. This review focuses on GOS
production from synthesis to purification processes. Physicochemical characteristics, physiological effects, and applications
of these prebiotic ingredients are summarized. Regulatory aspects of GOS-containing food products are also highlighted
with emphasis on the current process of health claims evaluation in Europe.Agência da
Inovação-Progama IDEIA (Portugal)Fundação para a Ciência e a Tecnologia (FCT
Bactericidal Activity of the Human Skin Fatty Acid cis-6-Hexadecanoic Acid on Staphylococcus aureus
Human skin fatty acids are a potent aspect of our innate defenses, giving surface protection against potentially invasive organisms. They provide an important parameter in determining the ecology of the skin microflora, and alterations can lead to increased colonization by pathogens such as Staphylococcus aureus. Harnessing skin fatty acids may also give a new avenue of exploration in the generation of control measures against drug-resistant organisms. Despite their importance, the mechanism(s) whereby skin fatty acids kill bacteria has remained largely elusive. Here, we describe an analysis of the bactericidal effects of the major human skin fatty acid cis-6-hexadecenoic acid (C6H) on the human commensal and pathogen S. aureus. Several C6H concentration-dependent mechanisms were found. At high concentrations, C6H swiftly kills cells associated with a general loss of membrane integrity. However, C6H still kills at lower concentrations, acting through disruption of the proton motive force, an increase in membrane fluidity, and its effects on electron transfer. The design of analogues with altered bactericidal effects has begun to determine the structural constraints on activity and paves the way for the rational design of new antistaphylococcal agents
"The European Neighbourhood Policy (ENP): Extending Governance beyond Borders?"
In this paper I argue that the development of the European Neighbourhood Policy (ENP) can be understood as a form of ‘externalization of EU governance’. In 2004 and 2007, the EU enlarged to encompass twelve new member states and thus acquired a new neighbourhood, notably in Eastern Europe. Russia, Ukraine, Belarus and Moldova now share a common border with the EU. Since 2001/02, the EU has been developing the ENP to cope with the challenges resulting from this new political landscape, and as such, the ENP is now the primary instrument through which EU governance is externalized. With the exception of Belarus and Russia, the European Union’s Eastern neighbours are intent on acquiring EU membership. The EU, in turn, is keen on maintaining its Eastern borders safe and secure from external risks such as illegal migration, environmental degradation and economic crisis. In order to meet these objectives, the EU promotes democratic and economic reforms in the countries located along its Eastern border and in doing so strives to foster political stability and security in the wider Europe. While hierarchy and negotiation constitute the dominant modes of governance in enlargement, this paper will demonstrate that coordination and competition – albeit in the shadow of hierarchy – are the most central modes of governance discernible within the European Neighbourhood Policy
Antifungal Hydroxy Fatty Acids Produced during Sourdough Fermentation: Microbial and Enzymatic Pathways, and Antifungal Activity in Bread
Lactobacilli convert linoleic acid to hydroxy fatty acids; however, this conversion has not been demonstrated in food fermentations and it remains unknown whether hydroxy fatty acids produced by lactobacilli have antifungal activity. This study aimed to determine whether lactobacilli convert linoleic acid to metabolites with antifungal activity and to assess whether this conversion can be employed to delay fungal growth on bread. Aqueous and organic extracts from seven strains of lactobacilli grown in modified De Man Rogosa Sharpe medium or sourdough were assayed for antifungal activity. Lactobacillus hammesii exhibited increased antifungal activity upon the addition of linoleic acid as a substrate. Bioassay-guided fractionation attributed the antifungal activity of L. hammesii to a monohydroxy C-18:1 fatty acid. Comparison of its antifungal activity to those of other hydroxy fatty acids revealed that the monohydroxy fraction from L. hammesii and coriolic (13-hydroxy-9,11-octadecadienoic) acid were the most active, with MICs of 0.1 to 0.7 g liter(-1). Ricinoleic (12-hydroxy-9-octadecenoic) acid was active at a MIC of 2.4 g liter(-1). L. hammesii accumulated the monohydroxy C-18:1 fatty acid in sourdough to a concentration of 0.73 +/- 0.03 g liter(-1) (mean +/- standard deviation). Generation of hydroxy fatty acids in sourdough also occurred through enzymatic oxidation of linoleic acid to coriolic acid. The use of 20% sourdough fermented with L. hammesii or the use of 0.15% coriolic acid in bread making increased the mold-free shelf life by 2 to 3 days or from 2 to more than 6 days, respectively. In conclusion, L. hammesii converts linoleic acid in sourdough and the resulting monohydroxy octadecenoic acid exerts antifungal activity in bread
Towards an ‘ever more differentiated Union'?: Measuring demand for European (dis)integration
Since the ratification of the Maastricht Treaty, the EU has seen a dramatic increase in the use of various mechanisms of differentiation, be it temporal, territorial or functional. As of today, more than fifty percent of EU policies have been affected by differentiation. While much of the existing literature on differentiated integration has focused on the supply side of differentiation, little attention has been paid to the demand for differentiation. Based on party manifesto and Eurobarometer analysis, this chapter attempts to fill a gap in the literature by focusing on two domestic actors that shape demand for differentiation, namely political parties and public opinion. It is argued that given the saliency of this issue, party positions on European integration are now best measured through the lens of preferences on differentiation, per policy area. The chapter further demonstrates that even more needs to be done to analyze how citizens understand the causes and effects of differentiated integration; countries that experience differentiation as a result of referendums tend to display the strongest support for national decision-making in various policy areas
- …