In vitro screening of probiotics and synbiotics according to anti-inflammatory and anti-proliferative effects

There is emerging evidence of the efficiency of probiotic, prebiotic and synbiotic treatments in inflammatory bowel diseases (IBDs) and one of their long-term complications, colorectal cancer (CRC). In this study, various strains of probiotic lactic acid bacteria, prebiotic glucooligosaccharides (GOS) or a synbiotic combination of the two were screened for anti-inflammatory and anti-proliferative effects in different in vitro models in the context of such diseases. To mimic IBD response to Gram negative bacteria, HT-29 cells were sensitised to inflammatory response to lipopolysaccharide (LPS) by IFNγ which increased expression of TLR4, the LPS biosensor, and were then treated by probiotics, prebiotics and synbiotics. Secreted IL-8 and activated NF-κB were monitored as inflammation biomarkers. A selection of active strains were then subjected to a second inflammatory cell culture model consisting of inflammatory activated transgenic Caco-2 cells transfected by a reporter gene under the control of NF-κB inducible promoter. Quantification of reporter gene expression allowed us to demonstrate some probiotic inhibitory properties or to confirm such characteristics in two different models. Proliferation of cancerous HT-29 cells was monitored by XTT assay. Only three probiotic strains induced a proliferation decrease, but with a lack of reproducibility. Binary or ternary probiotic associations, complemented or not by prebiotic GOS, significantly decreased proliferation, especially with a synbiotic association of Bifidobacterium breve, Lactococcus lactis and oligoalternan, a GOS. This combination was selected for the following experiments. We showed the involvement of both bacterial and carbohydrate compounds of this synbiotic in the observed effect by dose range tests. We demonstrated that this decrease in proliferation may be due to an induction of a differentiated phenotype, as shown by the up-regulation of intestinal alkaline phosphatase, a biomarker of differentiation, monitored by real-time RT-PCR in HT-29 cells treated by the selected synbiotics. Thus, this study demonstrates the ability of probiotics to exert anti-inflammatory effects and shows some anti-proliferative characteristics for a specific synbiotics. These products should be further evaluated in animal models to confirm the in vitro results.     

Prevalence and characterization of Salmonella enterica serovar Weltevreden from imported seafood

During 2001-2005, 210 Salmonella enterica strains were isolated from seafood samples imported into US. Strains of S. enterica serovar Weltevreden were the most predominantly found among the 64 different serovars isolated. A total of 37 Salmonella Weltevreden isolates were characterized by pulsed-field gel electrophoresis (PFGE), plasmid profiles and antibiotic susceptibility to assess genetic diversity. Our results showed a low frequency of antibiotic resistance; 35 of the 37 isolates were sensitive to ampicillin, tetracycline, chloramphenicol, gentamicin, sulfisoxazole, streptomycin and kanamycin. Only two isolates, from samples originating in the Philippines and India, showed resistance to ampicillin and tetracycline and to streptomycin, sulfisoxazole and tetracycline, respectively. Of the 37 isolates, two isolates did not carry any plasmid and 35 isolates harbored several small and mega-plasmids. These isolates were differentiated into 10 distinct types based on plasmid profiles. Four different PFGE clusters were obtained with a genetic similarity of 66-76%. Four groups of isolates (formed by two or three isolates each) showed 100% similarity in the PFGE profiles. One of these groups included strains isolated in Vietnam in 2003, 2004 and 2005 from fish and shrimp. The other groups included strains isolated in Vietnam, Indonesia and Thailand in 2000, 2004 and 2005 from snail, shrimp and fish. Our findings show genetic diversity and temporal persistence of S. enterica serovar Weltevreden in recently monitored seafood imports.     

Dietary exposure of the Belgian population to emulsifiers E481 (sodium stearoyl-2-lactylate) and E482 (calcium stearoyl-2-lactylate)

A dietary exposure assessment of food emulsifiers E481 (sodium stearoyl-2-lactylate) and E482 (calcium stearoyl-2-lactylate) in the Belgian population was performed. Nationally representative food consumption data from the Belgian National Food Consumption Surveys 2004 (BNFCS2004) and 2014 (BNFCS2014) were used for calculations. A conservative approach (combining individual food consumption data with the maximum permitted level (MPL) of foods (tier 2), was compared with more refined estimates (combining individual food consumption data with actual concentrations measured in food products available on the Belgian market (tier 3)). Estimated daily intakes were compared to the acceptable daily intake (ADI) of the stearoyl-2-lactylates. The results of tier 2 demonstrated that 92% of the children (3–9 years), 53% of the adolescents (10–17 years), 15% of the adults (18–64 years) and 26% of the elderly (64–98 years) had a potential intake higher than the ADI. When replacing the MPL with maximum analysed concentration levels in foods, daily intake estimates decreased dramatically. The estimated daily intake of the food emulsifiers was below the ADI for all age groups, except for a small percentage of children (1.9%) for which the intake exceeded the ADI. The main contributors to the exposure of E481 and E482 were bread, rolls and fine bakery wares.     

Short communication: Genomic prediction using imputed whole-genome sequence variants in Brown Swiss Cattle

The accuracy of genomic prediction determines response to selection. It has been hypothesized that accuracy of genomic breeding values can be increased by a higher density of variants. We used imputed whole-genome sequence data and various single nucleotide polymorphism (SNP) selection criteria to estimate genomic breeding values in Brown Swiss cattle. The extreme scenarios were 50K SNP chip data and whole-genome sequence data with intermediate scenarios using linkage disequilibrium-pruned whole-genome sequence variants, only variants predicted to be missense, or the top 50K variants from genome-wide association studies. We estimated genomic breeding values for 3 traits (somatic cell score, nonreturn rate in heifers, and stature) and found differences in accuracy levels between traits. However, among different SNP sets, accuracy was very similar. In our analyses, sequence data led to a marginal increase in accuracy for 1 trait and was lower than 50K for the other traits. We concluded that the inclusion of imputed whole-genome sequence data does not lead to increased accuracy of genomic prediction with the methods.     

Pyrite-catalysed coal liquefaction using quinoline/tetrahydroquinoline as an H-donor system

Pyrite catalyses the hydrogénation of the N-containing ring in quinoline (Q) to form the active H-donor, 1,2,3,4-tetrahydroquinoline, (THQ). THQ is shown to dissolve coal readily at 325 °C, a temperature lower than that commonly used in most liquefaction processes. Pyrite is effective for maintaining the H-donor capacity of the solvent by hydrogenating the Q formed after H-donation, thereby providing the high THQ/Q required for sustained operation. Qualitative observations suggest that some source of hydrogen, either molecular or donor, must be present to prevent retrogressive reactions of coal fragments.     

Analytische Differenz-IR-Spektrometrie von Mehrkomponentenkunststoffen und Copolymeren. I. Identifizierung der Komponenten in Polymergemischen

The introduction of computer-assisted IR and FTIR spectrometers has greatly enlarged the possibilities of qualitative and quantitative analysis of macromolecular multi-component systems. By using the digitally stored standard spectra of the components of a system the composition of this system can be evaluated under the condition that spectral superposition is valid. Since this condition is frequently invalid it is preferable, for the analysis of a system with n spectroscopically defined components, to choose n compositions within an optimal range within the (n — 1) dimensional Gibbs diagram. In real polymer blends with crystallizable components the degree of crystallinity of these components will be lower than in the unmixed polymers. This is probably due to the mutual interpenetration of the noncrystalline ranges of the different polymers. Highly filled materials can be identified quite reliably when the filler or reinforcing material is monodisperse. This ist the case, e.g., with dental cements (fillings). Organically filled construction materials with low concentrations of binder (e.g., fiber board) can be identified by difference spectrometry when the characteristic absorptions of the binder will not coincide with strong bands of the filler. — Artefacts may falsify a difference spectrum. Origins and consequences of artefacts will be discussed.     

Effects of raw materials,processing conditions and packaging on the quality of plantain chips

The effects of raw material, processing conditions and packaging on the quality of plantain chips were investigated. Two cultivars of plantain Musa spp—Agbagba and Obino lewai—as well as cooking banana were used for the study. The fruits were at stages 1 to 4 of the banana ripening chart. The study started with a consumer survey aimed at product definition. This was followed by series of experiments to determine the effects of raw material, processing conditions and packaging on the quality of plantain chips. A correlation analysis was also carried out on the physical and chemical characteristics of raw plantain. The work revealed that the stage of ripeness of raw material had some effect on the quality of chips as there was gradual increase in pulp/peel ratio and sugar was significantly different (P < 0·05). Moisture content of pulp/texture of pulp, texture of pulp/sugar content of pulp and texture of pulp/ripening stages were negatively correlated, while pulp/peel ratio and moisture content of pulp were positively correlated. Chips packed in 80 μm high-density polyethylene pouches and stored at various relative humidities had extended shelf-life compared with the low-density polyethylene packed chips stored at the same relative humidities. This was due to the inadequacy of the low-density polyethylene in giving the required protection against moisture transmission thereby resulting in soggy chips in shorter periods. The implication of the findings on the formulation of a guideline for the processing of a good-quality plantain chips for the marketing system is discussed.     

Application of multimedia models for screening assessment of long-range transport potential and overall persistence

We propose a multimedia model-based methodology to evaluate whether a chemical substance qualifies as POP-like based on overall persistence (Pov) and potential for long-range transport (LRTP). It relies upon screening chemicals against the Pov and LRTP characteristics of selected reference chemicals with well-established environmental fates. Results indicate that chemicals of high and low concern in terms of persistence and long-range transport can be consistently identified by eight contemporary multimedia models using the proposed methodology. Model results for three hypothetical chemicals illustrate that the model-based classification of chemicals according to Pov and LRTP is not always consistent with the single-media half-life approach proposed by the UNEP Stockholm Convention and thatthe models provide additional insight into the likely long-term hazards associated with chemicals in the environment. We suggest this model-based classification method be adopted as a complement to screening against defined half-life criteria at the initial stages of tiered assessments designed to identify POP-like chemicals and to prioritize further environmental fate studies for new and existing chemicals.