Zinc Tolerance of Special Yeasts and Lactic Acid Bacteria for Use in the Food Industry

In order to address human zinc deficiency, fortifying staple foods with zinc is a safe and cost-effective solution. To ensure the nutritional properties and quality of a final product, zinc tolerance of the microorganisms involved in the fermentation is necessary. Bread, which is widely consumed, occupies a substantial place in many people’s diets, and is often based on a sourdough making process; thus, it might be an important headlining product. This study investigated the zinc tolerance of yeasts and lactic acid bacteria that are specifically suited to produce sourdough bread made with cricket powder hydrolysate and wheat flour. Amongst the yeasts, Kazachstania servazzii KAZ2 and Kazachstania unispora FM2 were only slightly affected in regard to cell growth and colony-forming ability when cultured in YPD broth spiked with 0.5 or 1 mM ZnSO4, respectively. Yarrowia lipolytica RO25 showed a higher tolerance for up to 2.5 mM zinc (ZnSO4). All the yeast strains were capable of accumulating zinc in the range between 200 and 400 fg/cell. The heterofermentative lactic acid bacterium Fructilactobacillus sanfranciscensis DG1 appeared to have a moderate zinc requirement and was homeostatically balanced, even under a high 20 mM extracellular ZnSO4 load. A better understanding of zinc homeostasis in yeast and lactic acid bacteria for food industry applications may lead to improvements in zinc fortification, which might contribute to diminishing Zn deficiencies, especially in vulnerable population groups

Groups, organizations, families and movements: The sociology of social systems between interaction and society

Kühl S. Groups, organizations, families and movements: The sociology of social systems between interaction and society. Systems Research and Behavioral Science. 2020;37(3):496-515.In enhancing a proposal by Luhmann, this contribution shows that it is possible to locate different types of systems between ‘face‐to‐face‐interaction’ and ‘society’: groups, organizations, families and protest movements. The common ground of these is that they use membership to attribute persons to the system or not. However, they differ fundamentally in regard to how they understand membership. In contrast to Luhmann's differentiation between interaction, organization and society, it is not only possible to imagine different types of interlocking systems but also coequal combinations of and transitions between the different types of social systems

Ungerecht, aber nützlich. Zur Verteilung der wissenschaftlichen Reputation

Kieserling A. Ungerecht, aber nützlich. Zur Verteilung der wissenschaftlichen Reputation. In: Mau S, Schöneck NM, eds. (Un-)Gerechte (Un-)Gleichheiten. Edition Suhrkamp. Berlin: Suhrkamp; 2015: 54-65

Conformational state and charge determine the interfacial film formation and film stability of β-lactoglobulin

The mechanical stability of protein-stabilized emulsions depends on physiochemical interactions within the interfacial protein film. However, intermolecular interactions vary with the protein's conformational state and charge and may in turn affect the mechanical stability through modifications in the three-staged interfacial stabilization; migration, adsorption and film formation at the oil/water-interface. Therefore, the aim of our study was to investigate the different protein conformations within the interfacial stabilization process by applying bulk water conditions and to determine the protein film stability against mechanical stress. For this purpose, we analyzed the structure and interactions of β-lactoglobulin in water and at the oil/water-interface at pH 7, pH 7NaCl (containing 100 mM NaCl) and pH 9 with membrane-osmometry, Fourier-transform-infrared-spectroscopy, extrinsic fluorescence and ζ-potential. Moreover, we characterized the conformational state and charge in context with the molecule density and interfacial film properties via Langmuir trough analysis, interfacial shear and dilatational rheology. Distinct unfolding of monomers and dimers at pH 9 resulted in the lowest interfacial molecule density but at the same time the highest film stability due to pronounced structural flexibility. In comparison, β-lactoglobulin at pH 7 was monomeric, unfolding was less pronounced, and interfacial molecule density was higher. Electrostatic shielding of β-lactoglobulin dimers at pH 7NaCl resulted in the highest density but least stable protein film that approached low molecular weight surfactant behavior due to few and weak intermolecular interactions. Our research contributes to the control of the emulsion stability against mechanical stress by varying intermolecular interactions within the interfacial protein film

Entwicklung einer Nadelfraes-Versuchsanlage zur Oberflaechenbearbeitung von Baendern und Blechtafeln zum Abbau schaedigender Belastungen und Erhoehung der Arbeitssicherheit

SIGLEDEGerman

Entwicklung einer Nadelfraes-Versuchsanlage zur Oberflaechenbearbeitung von Baendern und Blechtafeln zum Abbau schaedigender Belastungen und Erhoehungen der Arbeitssicherheit Abschlussbericht. Abschlussdatum: August 1979

Technische Informationsbibliothek Hannover: RN 7543 (81-014) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman