Taking real-life seriously : an approach to decomposing context beyond 'environment' in living labs

The maturity of Living Labs has grown and several researchers have tried to create a uniform definition of what Living Labs are by emphasizing the multi-method and real-life, contextual approach. Although researchers thus recognize the importance of context in Living Labs, they do not provide insights into how context can be taken into account. The real-life context predominantly focuses on the in-situ use of a product during field trials where users are observed in their everyday life. The contribution of this paper will be twofold. By means of a case study we will show how context can be evaluated in the front end of design, so Living Lab researchers are no longer dependent on the readiness level of a product, and we will show how field trials can be evaluated in a more structured way to cover all components of context. By using a framework to evaluate the impact of context on product use, Living Lab researchers can improve the overall effectiveness of data gathering and analysis methods in a Living Lab project

Pseudomonads and bacilli as important spoilage organisms in the dairy industry : a taxonomic study

Raw cow's milk is a product of high nutritional value but this automatically implies it is a medium highly suitable for growth of spoilage organisms that negatively affect milk quality and safety through production of proteolytic and lipolytic enzymes and toxins. Two major groups of spoilage bacteria are recognized, namely pseudomonads and bacilli. Identification of members of these groups is hampered by their confusing taxonomic situation. Both taxa historically grew as dumping grounds for aerobic Gram-positive spore-forming rods in the case of bacilli, and aerobic Gram-negative rods in the case of pseudomonads, resulting in two very large, heterogeneous groups. As a consequence, members of these groups were often poorly identified based on identification tools with insufficient resolution, and usually only two major species were recognized in the issue of milk spoilage, namely Bacillus cereus and Pseudomonas fluorescens. Nonetheless, several studies on the identity of bacterial milk flora indicated diversity was much bigger than originally thought, and the dairy product spoilage issue is clearly not a story of Bacillus cereus and Pseudomonas fluorescens alone. The main objectives of this study were two-fold. The first goal was to accurately map the diversity of bacterial milk flora through a polyphasic identification approach of milk isolates, with focus on bacilli and pseudomonads. Additionally, the spoilage potentials of these isolates were assessed. The second goal was an attempt to resolve the complex taxonomic situation at least for subgroups within the bacilli (the genus Geobacillus) and pseudomonads (the Pseudomonas fluorescens group)

Monitoring the purity of industrial starter cultures using MALDI-TOF MS

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Neisseria oralis sp. nov., isolated from healthy gingival plaque and clinical samples

A polyphasic analysis was undertaken of seven independent isolates of Gram-negative cocci collected from pathological clinical samples from New York, Louisiana, Florida and Illinois and healthy subgingival plaque from a patient in Virginia, USA. The 16S rRNA gene sequence similarity among these isolates was 99.7–100 %, and the closest species with a validly published name was Neisseria lactamica (96.9 % similarity to the type strain). DNA–DNA hybridization confirmed that these isolates are of the same species and are distinct from their nearest phylogenetic neighbour, N. lactamica. Phylogenetic analysis of 16S and 23S rRNA gene sequences indicated that the novel species belongs in the genus Neisseria. The predominant cellular fatty acids were C16 : 0, summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) and C18 : 1ω7c. The cellular fatty acid profile, together with other phenotypic characters, further supports the inclusion of the novel species in the genus Neisseria. The name Neisseria oralis sp. nov. (type strain 6332T = DSM 25276T = LMG 26725T) is proposed

Hazenella coriacea gen. nov., sp nov., isolated from clinical specimens

A Gram-staining-positive, endospore-forming rod was isolated independently from clinical specimens in New York State, USA, once in 2009 and twice in 2011. The three isolates had identical 16S rRNA gene sequences and, based on their 16S rRNA gene sequence, are most closely related to the type strains of Laceyella sediminis and L. sacchari (94.6% similarity). The partial 23S rRNA gene sequences of the three strains were also 100% identical. Maximumlikelihood phylogenetic analysis suggests that the new isolates belong to the family Thermoactinomycetaceae. Additional biochemical and phenotypic characteristics of the strains support the family designation and suggest that the three isolates represent a single species. In each of the strains, the predominant menaquinone is MK-7, the diagnostic diamino acid is mesodiaminopimelic acid and the major cellular fatty acids are iso-C15 : 0, anteiso-C15 : 0 and iso-C13 : 0. The polar lipids are phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, four unknown phospholipids, four unknown aminophospholipids and an unknown lipid. It is proposed that the novel isolates represent a single novel species within a new genus, for which the name Hazenella coriacea gen. nov., sp. nov. is proposed. The type strain of Hazenella coriacea is strain 23436T (5DSM 45707T5LMG 27204T)

Emended descriptions of Bacillus sporothermodurans and Bacillus oleronius with the inclusion of dairy farm isolates of both species

Bacillus sporothermodurans is an industrially important micro-organism because of its ability to produce endospores which resist ultra high temperature (UHT) and industrial sterilization processes. It was described by Pettersson et al. (1996) based on seven genetically homogeneous isolates all from UHT-milk. Bacillus oleronius, the closest phylogenetic neighbor of B. sporothermodurans, was described by Kuhnigk et al. (1995), based on a single strain, isolated from the hindgut of the termite Reticulitermes santonensis. A polyphasic study of a heterogeneous collection of B. sporothermodurans and B. oleronius strains isolated from various sources and geographic origins led to an emended description of both species. Additional data presented are the results of fatty acids, quinones and/or cell wall analysis (polar lipids). DNA-DNA hybridizations confirmed 3 subgroups of strains obtained after SDS-PAGE analysis of cellular proteins as B. sporothermodurans. One named B. sporothermodurans strain (R-7489) was reclassified as a Bacillus fordii strain. The phenotypic profiles of both species were rather heterogeneous, sometimes different from the original descriptions and did not differ in a large number of characters, although B. oleronius generally gave stronger reactions in its positive tests than did B. sporothermodurans; the variable and weak reactions for both organisms with some substrates blurred the distinction between both. However, differences in polar lipid, SDS-PAGE and menaquinone profiles clearly allow distinction between the two species

Neisseria oralis sp. nov., isolated from healthy gingival plaque and clinical samples

A polyphasic analysis was undertaken of seven independent isolates of Gram-negative cocci collected from pathological clinical samples from New York, Louisiana, Florida and Illinois and healthy subgingival plaque from a patient in Virginia, USA. The 16S rRNA gene sequence similarity among these isolates was 99.7–100 %, and the closest species with a validly published name was Neisseria lactamica (96.9 % similarity to the type strain). DNA–DNA hybridization confirmed that these isolates are of the same species and are distinct from their nearest phylogenetic neighbour, N. lactamica. Phylogenetic analysis of 16S and 23S rRNA gene sequences indicated that the novel species belongs in the genus Neisseria. The predominant cellular fatty acids were C16 : 0, summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) and C18 : 1ω7c. The cellular fatty acid profile, together with other phenotypic characters, further supports the inclusion of the novel species in the genus Neisseria. The name Neisseria oralis sp. nov. (type strain 6332T = DSM 25276T = LMG 26725T) is proposed

Tardiphagia robiniae gen. nov., sp. nov., a new genus in the family Bradyrhizobiaceae isolated from Robinia pseudoacacia in Flanders (Belgium)

Gram-negative, rod-shaped bacteria were isolated from Robinia pseudoacacia root nodules. On the basis of the 16S rRNA gene phylogeny, they are closely related to Bradyrhizobium, Rhodopseudomonas and Nitrobacter species (97% sequence similarity), belonging to the class Alphaproteobacteria and family Bradyrhizobiaceae. The results of physiological and biochemical tests together with sequence analysis of housekeeping genes (atpD, dnaK, gyrB, recA and rpoB) allowed differentiation of this group from other validly published Bradyrhizobiaceae genera. NodA, nodC and nifH genes could not be amplified. On the basis of genotypic and phenotypic data, these organisms represent a novel genus and species for which the name Tardiphaga robiniae gen. nov., sp. nov. (LMG 26467T=CCUG 61473T), is proposed

Yeast quality in industrial fermentations

Industrial pitching yeast for production of alcoholic beverages or fuel ethanol should ferment the sugars fast and completely. Fresh optimal propagated yeast can normally fulfill these industrial demands. However, cropped, treated, stored or dried yeast is in most cases not a good pitching yeast due to its bad physiological condition. The amount of storage polysaccharides - glycogen and trehalose - can be too low, the fluidity of the membrane for active transport of fermentable sugars can be insufficient, ATP regeneration can be too slow and the enzymes for glycolysis can have limited activity. Quality parameters for yeast are viability and vitality. Vitality is a measure for the metabolic capacity of the yeast. Yeast with high vitality can ferment well under stress conditions such as high temperature, high alcohol concentration, osmotic pressure and hydrostatic pressure. Pitching yeast with the same viability can have a completely different fermentation capacity. Most of the methods described in literature for determination of viability and vitality of yeast were tested by us. For the study of industrial yeasts, the following methods were used: plating (as a reference method for the viability), methylene blue staining (microscope and Cellometer), fluorescence flow cytometry with propidiumjodide-Syto 13 and determination of intracellular pH (ICP) and number of scars. The ICP is important for glycolysis and glucogenesis and thus for metabolic capacity of the yeast. The ICP is determined with the pH-sensitive SNARF fluorochrome. Average bud scar numbers are counted microscopically after Calcofluor white staining and allow cell age estimation of yeast. A further complication of industrial fermentations is that the exact composition of the fermentation liquid is not known. Even if the yeast is in good condition, fermentation can stuck due to shortening of zinc, essential amino acids and fatty acids. Also the sugar spectrum can be out of balance, yeast inhibitors present in the fermentation liquid or the fermentation liquid can have a PYF (Premature Yeast Flocculation) potential. We have shown for brewery fermentations that the differences between industrial used yeasts are huge, even under the same fermentation conditions, showing the importance of a good yeast management and the need for more investigation in this field. By using good prepared pitching yeast with the necessary metabolic capacity and by adapting the composition of the fermentation liquid, it is possible to guarantee successful fermentation. Case studies of industrial yeast fermentations will provide the essential information needed therefore. Especially for new industrial fermentations, as high gravity, short, and simultaneous saccharification fermentations, yeast quality and composition of the fermentation liquid are critical. This stresses the need for good control of the latter to solve the fermentation problems