Benedikt Sas

Butyric acid-producing anaerobic bacteria as a novel probiotic treatment approach for inflammatory bowel disease

Inflammatory bowel disease (IBD), of which Crohn’s disease (CD) and ulcerative colitis (UC) are the most common manifestations, is characterized by chronic inflammation of the lining of the gastrointestinal tract, which causes severe watery and bloody diarrhoea, and abdominal pain. IBD is often debilitating and is characterized by onset at a young age and extra-intestinal manifestations. Whereas CD can affect any part of the gastrointestinal tract, UC is usually confined to the colon and rectum. IBD is an emerging disease and the incidence amounts to 20/100 000 in Europe and North America. There is a link with the social and economic development of the countries: the increase in IBD was first seen in northern Europe and North America, followed by the rest of Europe, Japan, South America and certain parts of Asia (Cohen, 2000; Ouyang et al., 2005). Although the exact aetiopathogenesis of IBD are not clear, it is widely accepted that the disease derives from an inappropriate immune response in genetically susceptible individuals as the result of a complex interaction between environmental factors, the microbiota and the intestinal immune system (Danese & Fiocchi, 2006).

Butyricicoccus pullicaecorum in inflammatory bowel disease

Objective Many species within the phylum Firmicutes are thought to exert anti-inflammatory effects. We quantified bacteria belonging to the genus Butyricicoccus in stools of patients with ulcerative colitis (UC) and Crohns disease (CD). We evaluated the effect of Butyricicoccus pullicaecorum in a rat colitis model and analysed the ability to prevent cytokine-induced increases in epithelial permeability. Design A genus-specific quantitative PCR was used for quantification of Butyricicoccus in stools from patients with UC or CD and healthy subjects. The effect of B pullicaecorum on trinitrobenzenesulfonic (TNBS)-induced colitis was assessed and the effect of B pullicaecorum culture supernatant on epithelial barrier function was investigated in vitro. Results The average number of Butyricicoccus in stools from patients with UC and CD in active (UC: 8.61 log10/g stool; CD: 6.58 log10/g stool) and remission phase (UC: 8.69 log10/g stool; CD: 8.38 log10/g stool) was significantly lower compared with healthy subjects (9.32 log10/g stool) and correlated with disease activity in CD. Oral administration of B pullicaecorum resulted in a significant protective effect based on macroscopic and histological criteria and decreased intestinal myeloperoxidase (MPO), tumour necrosis factor α (TNFα) and interleukin (IL)-12 levels. Supernatant of B pullicaecorum prevented the loss of transepithelial resistance (TER) and the increase in IL-8 secretion induced by TNFα and interferon γ (IFN gamma) in a Caco-2 cell model. Conclusions Patients with inflammatory bowel disease have lower numbers of Butyricicoccus bacteria in their stools. Administration of B pullicaecorum attenuates TNBS-induced colitis in rats and supernatant of B pullicaecorum cultures strengthens the epithelial barrier function by increasing the TER.

Efficient method for (lyso)phospholipid class separation by high-performance liquid chromatography using an evaporative light-scattering detector

A simple high-performance liquid chromatography method with evaporative light-scattering detection has been devised in order to separate and quantify the major phospholipid and lysophospholipid classes. HPLC analyses were performed with a diol-silica column and ternary gradient elution. Standard curves were drawn up for each of the (lyso)phospholipids involved.

Progress towards butyrate-producing pharmabiotics: Butyricicoccus pullicaecorum capsule and efficacy in TNBS models in comparison with therapeutics

We read with interest the commentary of Philippe Marteau1 on our study2 in which the author rightly questions the therapeutic value of butyrate-producing bacteria as pharmabiotics in humans because of their difficulty to grow in vitro. While indeed lactic acid bacteria are easy to grow but seem to have limited efficacy, the butyrate-producing bacteria from Clostridium cluster IV and XIVa are promising candidates as pharmabiotics, provided that the strains can be cultured and formulated in a stable way. Butyricicoccus pullicaecorum easily grows under anaerobic conditions in M2GSC medium reaching 108 cfu/mL after 24 h incubation. Our group further evaluated the survival and viability of B pullicaecorum in hydroxypropylmethylcellulose (HPMC) capsules after they were anaerobically lyophilised in horse serum supplemented with 7.5% trehalose and 1 mg/mL cysteine HCl and only observed a reduction of 1 log after 7 months. Now, after 15 months of storage at 4°C, still 107 …

Comparison of response formats and concurrent hedonic measures for optimal use of the EmoSensory® Wheel

The study of emotional and sensory profiling with food products is gaining momentum in the field of sensory research. These methods can be applied in order to obtain a broader consumer perspective on product performance beyond traditional hedonic measurements (Jiang, King, & Prinyawiwatkul, 2014; Varela & Ares, 2012). The EmoSensory® Wheel, a recently introduced method which combines emotional and sensory assessment in a wheel questionnaire format is one example of conducting such a task in a consumer-friendly way. However, little is known about its performance compared to a traditional list-based questionnaire format. This comparison is undertaken in this study for two product categories (chocolate and yogurt). Further, two methodological issues are addressed by (i) comparing the use of Check-All-That-Apply (CATA) and rate-all-that-apply (RATA) response formats and (ii) examining whether the method impacts on the concurrent hedonic product assessment for two product categories (chocolate and yogurt). Although both questionnaire formats showed similar findings, more consumers preferred the wheel questionnaire format. Regarding the latter, CATA and RATA scaling yielded similar performance and no influence on the concurrent hedonic assessment was found. This study lends further support for combining emotional and sensory measurements using the EmoSensory® profile, which is of interest for food scientists and the food industry.

The effect of the research setting on the emotional and sensory profiling under blind, expected, and informed conditions: A study on premium and private label yogurt products

Although sensory and emotional evaluation of food products mostly occurs in a controlled laboratory environment, it is often criticized as it may not reflect a realistic situation for consumers. Moreover, products are mainly blind evaluated by participants, whereas external factors such as brand are often considered as key drivers of food choice. This study aims to examine the role of research setting (central location test versus home-use test) and brand information on the overall acceptance, and sensory and emotional profiling of 5 strawberry-flavored yogurts. Thereby, private label and premium brands are compared under 3 conditions: blind, expected, and informed (brand information). A total of 99 adult subjects participated in 3 sessions over 3 consecutive weeks. Results showed that overall liking for 2 yogurt samples was higher in the laboratory environment under the informed evaluation condition, whereas no effect of research setting was found under the blind and expected conditions. Although emotional profiles of the products differed depending on the research setting, this was less the case for the sensory profiles. Furthermore, brand information clearly affected the sensory perception of certain attributes but had less influence on overall liking and emotional profiling. These results indicate that both scientists and food companies should consider the effect of the chosen methodology on ecological validity when conducting sensory research with consumers because the laboratory context could lead to a more positive evaluation compared with a home-use test.

Development and validation of ultra-high-performance liquid chromatography–tandem mass spectrometry methods for the simultaneous determination of beauvericin, enniatins (A, A1, B, B1) and cereulide in maize, wheat, pasta and rice

Rapid and accurate UPLC-MS/MS methods for the simultaneous determination of beauvericin and the related enniatins (A, A1, B, B1), together with cereulide were successfully developed and validated in cereal and cereal-based food matrices such as wheat, maize, rice and pasta. Although these emerging foodborne toxins are of different microbial origin, the similar structural, toxicological and food safety features provided rationale for their concurrent detection in relevant food matrices. A Waters Acquity UPLC system coupled to a Waters Quattro Premier XE™ Mass Spectrometer operating in ESI+ mode was employed. Sample pretreatment involved a fast and simple liquid extraction of the target toxins without any further clean-up step. For all toxins the sample preparation resulted in acceptable extraction recoveries with values of 85-105% for wheat, 87-106% for maize, 84-106% for rice and 85-105% for pasta. The efficient extraction protocol, together with a fast chromatographic separation of 7min allowed substantial saving costs and time showing its robustness and performance. The validation of the developed method was performed based on Commission Decision 2002/657/EC. The obtained limits of detection ranged from 0.1 to 1.0μgkg-1 and the limits of quantification from 0.3 to 2.9μgkg-1 for the targeted toxins in the selected matrices. The obtained sensitivities allow detection of relevant toxicological concentrations. All relative standard deviations for repeatability (intra-day) and intermediate precision (inter-day) were lower than 20%. Trueness, expressed as the apparent recovery varied from 80 to 107%. The highly sensitive and repeatable validated method was applied to 57 naturally contaminated samples allowing detection of sub-clinical doses of the toxins.

Won’t we scare them? The impact of communicating uncontrollable risks on the public’s perception

Authorities often refrain from communicating risks out of fear to arouse negative feelings amongst the public and to create negative reactions in terms of the public’s behavior. This study examines the impact of communicating risks on the public’s feelings and behavioral intentions regarding an uncontrollable risk related to fresh produce. In addition, the impact of risk communication is compared between a situation in which the risk either does or does not develop into a crisis, by means of a 2 (risk communication vs. no risk communication) × 2 (crisis communication vs. no crisis communication) between-subjects factorial design. The results show that communicating risks has a positive impact on the behavioral intention to keep on eating fresh produce compared to when no risk communication was provided, as it reduces negative feelings amongst the public. In addition, the findings illustrate that when a risk develops into an actual crisis, prior risk communication can result in greater trust in the government and reduce perceived government responsibility for the crisis when the crisis hits. Based on these findings, it can be suggested that risk communication is an effective tool for authorities in preparing the public for potential crises. The findings indicate that communicating risks does not raise negative reactions amongst the public, on the contrary, and that it results in more positive perceptions of the authorities.

Affective and cognitive reactions towards emerging food safety risks in Europe

Climate change and globalization may impact the microbiological food safety on fresh produce that is eaten raw. Hence, food risk communication to inform consumers needs to be carried out. The present study investigates affective and cognitive reactions of individuals towards a risk message with regard to the emerging food safety risks, using the risk-as-feelings theory and the affect heuristic as a theoretical basis. This research elaborates on whether these reactions towards a risk message vary across some European countries (i.e. Norway, Spain, Serbia and Belgium). The results show that compared to affective reactions, cognitive reactions have a higher predictive influence on behavioural intentions (i.e. the intention to alert loved ones, rinse fresh produce better, think about how to avert the risk and seek information). Both affective and cognitive reactions, as well as their predictive impact, differ significantly amongst the countries. Trust in the government, subjective knowledge about the topic and behavioural intentions differ as well per country. Based on these varying results of the impacts of affective and cognitive reactions on behavioural intentions that were observed in different countries, it is recommended that risk communication strategies be adapted on a national rather than on a European level.

Microbial Community Dynamics and Response to Plant Growth-Promoting Microorganisms in the Rhizosphere of Four Common Food Crops Cultivated in Hydroponics.

Plant growth promoting microorganisms (PGPMs) of the plant root zone microbiome have received limited attention in hydroponic cultivation systems. In the framework of a project aimed at the development of a biological life support system for manned missions in space, we investigated the effects of PGPMs on four common food crops (durum and bread wheat, potato and soybean) cultivated in recirculating hydroponic systems for a whole life cycle. Each crop was inoculated with a commercial PGPM mixture and the composition of the microbial communities associated with their root rhizosphere, rhizoplane/endosphere and with the recirculating nutrient solution was characterised through 16S- and ITS-targeted Illumina MiSeq sequencing. PGPM addition was shown to induce changes in the composition of these communities, though these changes varied both between crops and over time. Microbial communities of PGPM-treated plants were shown to be more stable over time. Though additional development is required, this study highlights the potential benefits that PGPMs may confer to plants grown in hydroponic systems, particularly when cultivated in extreme environments such as space.