Effect of dairy-based protein sources and temperature on growth, acidification and exopolysaccharide production of Bifidobacterium strains in skim milk

The aim of the present study was to find out the best growing conditions for exopolysaccharide (EPS) producing bifidobacteria, which improve their functionality in yoghurt-like products. Two Bifidobacterium strains were used in this study, Bifidobacterium longum subsp. infantis CCUG 52486 and Bifidobacterium infantis NCIMB 702205. In the first part of the study the effect of casein hydrolysate, lactalbumin hydrolysate, whey protein concentrate and whey protein isolate, added at 1.5% w/v in skim milk, was evaluated in terms of cell growth and EPS production; skim milk supplemented with yeast extract served as the control. Among the various nitrogen sources, casein hydrolysate (CH) showed the highest cell growth and EPS production for both strains after 18 h incubation and therefore it was selected for subsequent work. Based on fermentation experiments using different levels of CH (from 0.5 to 2.5% w/v) it was deduced that 1.5% (w/v) CH resulted in the highest EPS production, yielding 102 and 285 mg L− 1 for B. infantis NCIMB 702205 and B. longum subsp. infantis CCUG 52486, respectively. The influence of temperature on growth and EPS production of both strains was further evaluated at 25, 30, 37 and 42 °C for up to 48 h in milk supplemented with 1.5% (w/v) CH. The temperature had a significant effect on growth, acidification and EPS production. The maximum growth and EPS production were recorded at 37 °C for both strains, whereas no EPS production was observed at 25 °C. Lower EPS production for both strains were observed at 42 °C, which is the common temperature used in yoghurt manufacturing compared to that at 37 °C. The results showed that the culture conditions have a clear effect on the growth, acidification and EPS production, and more specifically, that skim milk supplemented with 1.5% (w/v) CH could be used as a substrate for the growth of EPS-producing bifidobacteria, at 37 °C for 24 h, resulting in the production of a low fat yoghurt-like product with improved functionality.

Emulsifying, rheological and physicochemical properties of exopolysaccharide produced by Bifidobacterium longum subsp. infantis CCUG 52486 and Bifidobacterium infantis NCIMB 702205

The rheological, emulsification and certain physicochemical properties of purified exopolysaccharides (EPS) of Bifidobacterium longum subsp. infantis CCUG 52486 and Bifidobacterium infantis NCIMB 702205 were studied and compared with those of guar gum and xanthan gum. The two strains were grown in skim milk supplemented with 1.5% (w/v) casein hydrolysate at 37 ◦C for 24 h; they both produced heteropolysaccharides with different molecular mass and composition. The carbohydrate content of both polymers was more than 92% and no protein was detected. The EPS of B. longum subsp. infantis CCUG 52486 showed highly branched entangled porous structure under scanning electron microscopy. Higher intrinsic viscosity was observed for the EPS of B. longum subsp. infantis CCUG 52486 compared to the EPS of B. infantis NCIMB 702205 and guar gum. Both polymers showed pseudoplastic non-Newtonian fluid behaviour in an aqueous solution. The EPS of B. infantis NCIMB 702205 and B. longum subsp. infantis CCUG 52486 produced more stable emulsions with orange oil, sunflower seed oil, coconut oil and xylene compared to guar and xanthan gum. The EPS of B. longum subsp. infantis CCUG 52486 is the most promising one for applications in the food industry, as it had higher intrinsic viscosity, higher apparent viscosity in aqueous solution, porous dense entangled structure and good emulsification activity.

Species richness declines and biotic homogenization have slowed down for NW-European pollinators and plants

Concern about biodiversity loss has led to increased public investment in conservation. Whereas there is a widespread perception that such initiatives have been unsuccessful, there are few quantitative tests of this perception. Here, we evaluate whether rates of biodiversity change have altered in recent decades in three European countries (Great Britain, Netherlands and Belgium) for plants and flower visiting insects. We compared four 20-year periods, comparing periods of rapid land-use intensification and natural habitat loss (1930–1990) with a period of increased conservation investment (post-1990). We found that extensive species richness loss and biotic homogenisation occurred before 1990, whereas these negative trends became substantially less accentuated during recent decades, being partially reversed for certain taxa (e.g. bees in Great Britain and Netherlands). These results highlight the potential to maintain or even restore current species assemblages (which despite past extinctions are still of great conservation value), at least in regions where large-scale land-use intensification and natural habitat loss has ceased.

A genome-wide association meta-analysis identifies new childhood obesity loci

Multiple genetic variants have been associated with adult obesity and a few with severe obesity in childhood; however, less progress has been made in establishing genetic influences on common early-onset obesity. We performed a North American, Australian and European collaborative meta-analysis of 14 studies consisting of 5,530 cases (≥95th percentile of body mass index (BMI)) and 8,318 controls (<50th percentile of BMI) of European ancestry. Taking forward the eight newly discovered signals yielding association with P < 5 × 10(-6) in nine independent data sets (2,818 cases and 4,083 controls), we observed two loci that yielded genome-wide significant combined P values near OLFM4 at 13q14 (rs9568856; P = 1.82 × 10(-9); odds ratio (OR) = 1.22) and within HOXB5 at 17q21 (rs9299; P = 3.54 × 10(-9); OR = 1.14). Both loci continued to show association when two extreme childhood obesity cohorts were included (2,214 cases and 2,674 controls). These two loci also yielded directionally consistent associations in a previous meta-analysis of adult BMI(1).

The secretome of alginate-encapsulated limbal epithelial stem cells modulates corneal epithelial cell proliferation

Limbal epithelial stem cells may ameliorate limbal stem cell deficiency through secretion of therapeutic proteins, delivered to the cornea in a controlled manner using hydrogels. In the present study the secretome of alginate-encapsulated limbal epithelial stem cells is investigated. Conditioned medium was generated from limbal epithelial stem cells encapsulated in 1.2% (w/v) calcium alginate gels. Conditioned medium proteins separated by 1-D gel electrophoresis were visualized by silver staining. Proteins of interest including secreted protein acidic and rich in cysteine, profilin-1, and galectin-1 were identified by immunoblotting. The effect of conditioned medium (from alginate-encapsulated limbal epithelial stem cells) on corneal epithelial cell proliferation was quantified and shown to significantly inhibit (Pwth. As secreted protein acidic and rich in cysteine was previously reported to attenuate proliferation of epithelial cells, this protein may be responsible, at least in part, for inhibition of corneal epithelial cell proliferation. We conclude that limbal epithelial stem cells encapsulated in alginate gels may regulate corneal epithelialisation through secretion of inhibitory proteins.

Long-term cultivation-independent microbial diversity analysis demonstrates that bacterial communities infecting the adult cystic fibrosis lung show stability and resilience.

Whilst not true in all cases, the microbial communities that chronically infect the airways of patients with CF can vary little over a year despite antibiotic perturbation. The species present tended to vary more between than within subjects, suggesting that each CF airway infection is unique, with relatively stable and resilient bacterial communities. The inverse relationship between community richness and disease severity is similar to findings reported in other mucosal infections.

Does bacterial density in cystic fibrosis sputum increase prior to pulmonary exacerbation?

These findings strongly suggest that CFPE do not generally result from increased bacterial density within the airways. Instead, data presented here are consistent with alternative models of pulmonary exacerbation.

Stability of dobutamine 500 mg in 50 ml syringes prepared using a Central Intravenous Additive Service

Objectives A pharmacy Central Intravenous Additives Service (CIVAS) provides ready to use injectable medicines. However, manipulation of a licensed injectable medicine may significantly alter the stability of drug(s) in the final product. The aim of this study was to develop a stability indicating assay for CIVAS produced dobutamine 500 mg in 50 ml dextrose 1% (w/v) prefilled syringes, and to allocate a suitable shelf life. Methods A stability indicating high performance liquid chromatography (HPLC) assay was established for dobutamine. The stability of dobutamine prefilled syringes was evaluated under storage conditions of 4°C (protected from light), room temperature (protected from light), room temperature (exposed to light) and 40°C (protected from light) at various time points (up to 42 days). Results An HPLC method employing a Hypersil column, mobile phase (pH=4.0) consisting of 82:12:6 (v/v/v) 0.05 M KH2PO4:acetonitrile:methanol plus 0.3% (v/v) triethylamine with UV detection at λ=280 nm was specific for dobutamine. Under different storage conditions only samples stored at 40°C showed greater than 5% degradation (5.08%) at 42 days and had the shortest T95% based on this criterion (44.6 days compared with 111.4 days for 4°C). Exposure to light also reduced dobutamine stability. Discolouration on storage was the limiting factor in shelf life allocation, even when dobutamine remained within 5% of the initial concentration. Conclusions A stability indicating HPLC assay for dobutamine was developed. The shelf life recommended for the CIVAS product was 42 days at 4°C and 35 days at room temperature when protected from light.

Assessing pragmatic interoperability for process alignment in collaborative working environment

This paper is an extension of our previous study on pragmatic interoperability assessment for process alignment. In this study, we conduct four case studies in industrial companies and hospitals in order to gather their viewpoints regarding the concerns when condensing process alignment in a collaborative working environment. Used techniques include interview, observation, and documentation. The collected results firstly are summarised into three layers based on our previous developed pragmatic assessment model, and then are transformed into the elements which constitutes the purposed method, and finally based on the summarised results we purpose a method for assessing pragmatic interoperability for process alignment in collaborative working environment. The method contains two parts: one gives all the elements of pragmatic interoperability that should be concerned when considering process alignment in collaborative working environment, and the other one is a supplementary method for dealing with technical concerns.

Information and knowledge management in complex systems

16th IFIP WG8.1 International Conference on Informatics and Semiotics in Organisations, ICISO 2015

Time-dependent gel to gel transformation of a peptide based supramolecular gelator

A dipeptide with a long fatty acid chain at its N-terminus gives hydrogels in phosphate buffer in the pH range 7.0–8.5. The hydrogel with a gelator concentration of 0.45% (w/v) at pH 7.46 (physiological pH) provides a very good platform to study dynamic changes within a supramolecular framework as it exhibits remarkable change in its appearance with time. Interestingly, the first formed transparent hydrogel gradually transforms into a turbid gel within 2 days. These two forms of the hydrogel have been thoroughly investigated by using small angle X-ray scattering (SAXS), powder X-ray diffraction (PXRD), field emission scanning electron microscopic (FE-SEM) and high-resolution transmission electron microscopic (HR-TEM) imaging, FT-IR and rheometric analyses. The SAXS and low angle PXRD studies substantiate different packing arrangements for the gelator molecules for these two different gel states (the freshly prepared and the aged hydrogel). Moreover, rheological studies of these two gels reveal that the aged gel is stiffer than the freshly prepared gel.

Rhodosporidium toruloides cultivated in NaCl-enriched glucose-based media: adaptation dynamics and lipid production

In the present report and for the first time in the international literature, the impact of the addition of NaCl upon growth and lipid production on the oleaginous yeast Rhodosporidium toruloides was studied. Moreover, equally for first time, lipid production by R. toruloides was performed under non-aseptic conditions. Therefore, the potentiality of R. toruloides DSM 4444 to produce lipid in media containing several initial concentrations of NaCl with glucose employed as carbon source was studied. Preliminary batch-flask trials with increasing amounts of NaCl revealed the tolerance of the strain against NaCl content up to 6.0% (w/v). However, 4.0% (w/v) of NaCl stimulated lipid accumulation for this strain, by enhancing lipid production up to 71.3% (w/w) per dry cell weight. The same amount of NaCl was employed in pasteurized batch-flask cultures in order to investigate the role of the salt as bacterial inhibiting agent. The combination of NaCl and high glucose concentrations was found to satisfactorily suppress bacterial contamination of R. toruloides cultures under these conditions. Batch-bioreactor trials of the yeast in the same media with high glucose content (up to 150 g/L) resulted in satisfactory substrate assimilation, with almost linear kinetic profile for lipid production, regardless of the initial glucose concentration imposed. Finally, fed-batch bioreactor cultures led to the production of 37.2 g/L of biomass, accompanied by 64.5% (w/w) of lipid yield. Lipid yield per unit of glucose consumed received the very satisfactory value of 0.21 g/g, a value amongst the highest ones in the literature. The yeast lipid produced contained mainly oleic acid and to lesser extent palmitic and stearic acids, thus constituting a perfect starting material for “second generation” biodiesel

Rejection thresholds (RjT) of sweet likers and dislikers

Sweetness is generally a desirable taste, however consumers can be grouped into sweet likers and dislikers according to optimally preferred sucrose concentrations. Understanding the levels of sweetness in products that are acceptable and unacceptable to both consumer groups is important to product development and for influencing dietary habits. The concentrations at which sucrose decreases liking (the rejection threshold; RjT) in liquid and semi-solid matrices were investigated in this study. Thirty six consumers rated their liking of 5 sucrose aqueous solutions; this identified 36% sweet likers (SL) whose liking ratings increased with increasing sucrose and 64% sweet dislikers (SD) whose liking ratings decreased above 6% (w/v) sucrose. We hypothesized that SL and SD would have different RjT for sucrose in products. This was tested by preparing 8 levels of sucrose in orange juice and orange jelly and presenting each against the lowest level in forced choice preference tests. In orange juice, as sucrose increased from 33g/L to 75g/L the proportion of people preferring the sweeter sample increased in both groups. However, at higher sucrose levels, the proportion of consumers preferring the sweet sample decreased. For SD, a RjT was reached at 380 g/L, whereas a significant RjT for SL was not reached. RjT in jelly were not reached as the sweetness in orange jelly was significantly lower than for orange juice (p<0.001). Despite statistically significant differences in rated sweetness between SL and SD (p=0.019), the extent of difference between the two groups was minor. The results implied that sweet liker status was not substantially related to differences in sweetness perception. Self-reported dietary intake of carbohydrate, sugars and sucrose were not significantly affected by sweet liker status. However the failure to find an effect may be due to the small sample size and future studies within a larger, more representative population sample are justifiable from the results of this study.