11 research outputs found
Present knowledge of the bacterial microflora in the extreme environment of sugar thick juice
The diversity of the bacterial population in sugar thick juice, an intermediate product in the production of beet sugar, which exhibits an extremes osmophilic environment with a water activity value (a(w)) less than 0.86, was assessed with both culture-dependent and -independent 16S ribosomal RNA (rRNA) gene-based analyses. In comparison with previous studies, the number of different thick juice bacterial species increased from 29 to 72. Remarkably, a limited, gram-positive, culturable flora, encompassing species of Bacillus, Staphylococcus and mainly Tetragenococcus dominated thick juice during storage, while a more heterogeneous and unculturable fraction of Acinetobacter, Sporolactobacillus and Thermus species could be detected in freshly produced thick juice. Notably, almost all bacteria detected in the thick juice were also detected in the air, emphasising the importance of further investigation and assessment of strategies to reduce (air) contamination during processing and storage. The discovery of the contamination source may be used for the development of management strategies for thick juice degradation resulting from microbial activity. (c) 2008 Elsevier Ltd. All rights reserved.status: publishe
Predominance of Tetragenococcus halophilus as the cause of sugar thick juice degradation
The industrial storage of sugar thick juice was simulated on a laboratory scale. Terminal Restriction Fragment Length Polymorphism (T-RFLP) analysis and the application of Clone Libraries in parallel with classical microbiology were used to study the bacterial diversity and all revealed a dominance (>99%) of Tetragenococcus halophilus during storage. The degradation of thick juice correlated with the appearance of L-lactic acid and high concentrations of T. halophilus. In addition, pure cultures of T. halophilus induced degradation of sterile thick juice. A specific PCR was developed to detect T. halophilus and industrial thick juice samples from Belgium, Germany and France all contained T. halophilus, suggesting a consistent association of this organism with thick juice. T. halophilus has been known only as a halophile thus far, and this report is the first to show an association of this organism with a sugar-rich environment.status: publishe
Genetic and physiological diversity of Tetragenococcus halophilus strains isolated from sugar- and salt-rich environments
Tetragenococcus halophilus is known to flourish in extreme salt environments. Recently, this
halophilic bacterium also appeared as the dominant microflora during storage of sugar thick juice,
an intermediate product of beet sugar production. Although T. halophilus can cause degradation
of thick juice, dominance of this bacterium does not always result in degradation. In this study
T. halophilus strains from high-salt and high-sugar environments, and in particular from degraded
and non-degraded thick juice, were compared in detail. Both physiological and genetic
characterization using Biolog, repetitive extragenic palindrome PCR fingerprinting (REP-PCR)
and random amplified polymorphic DNA (RAPD) technology, revealed clear differences between
T. halophilus strains isolated from salt- and sugar-rich environments. However, no strain pattern
could be specifically and systematically associated with degraded or non-degraded thick juice.
Remarkably, halophilic T. halophilus strains were not able to grow in sugar thick juice. Irrespective
of the differences between the strains from high-salt or high-sugar environments, DNA–DNA
hybridization grouped all strains within the species T. halophilus, except one isolate from sugar
thick juice that showed different physiological and genetic characteristics, and that may represent
a new species of Tetragenococcus.status: publishe
The Lower Saxony research network design of environments for ageing : towards interdisciplinary research on information and communication technologies in ageing societies
Worldwide, ageing societies are bringing challenges for independent living and healthcare. Health-enabling technologies for pervasive healthcare and sensor-enhanced health information systems offer new opportunities for care. In order to identify, implement and assess such new information and communication technologies (ICT) the 'Lower Saxony Research Network Design of Environments for Ageing' (GAL) has been launched in 2008 as interdisciplinary research project. In this publication, we inform about the goals and structure of GAL, including first outcomes, as well as to discuss the potentials and possible barriers of such highly interdisciplinary research projects in the field of health-enabling technologies for pervasive healthcare. Although GAL's high interdisciplinarity at the beginning slowed down the speed of research progress, we can now work on problems, which can hardly be solved by one or few disciplines alone. Interdisciplinary research projects on ICT in ageing societies are needed and recommended