The gut microbiota has a profound impact on human health. Emerging data show that dietary patterns are associated with different communities of bacterial species within the gut. Prevotella species have been correlated with plant-rich diets, abundant in carbohydrates and fibres. Dysbiosis within the gut ecosystem has been associated with the development of non-communicable diseases such as obesity, the metabolic syndrome, inflammatory bowel disease, irritable bowel syndrome, colorectal cancer, type 1 diabetes, allergies and other diseases. The purpose of this comprehensive literature review was to evaluate the available data on the impact of diet on the Prevotella genus, as a dietary fibre fermenter in the gut as well as its implications as a potential biomarker for homeostasis or disease state through its metabolite signature. Studies were identified by conducting PubMed, Web of Science Core Collection and Google Scholar electronic searches. We found eighty-five publications reporting the impact of dietary patterns on gut microbial communities, including Prevotella or Prevotella/Bacteroides ratio in particular. Moreover, the role of Prevotella species on health status was also evaluated. Prevotella possess a high genetic diversity, representing one of the important groups found in the oral cavity and large intestine of man. The gut commensal Prevotella bacteria contribute to polysaccharide breakdown, being dominant colonisers of agrarian societies. However, studies also suggested a potential role of Prevotella species as intestinal pathobionts. Further metagenomic studies are needed in order to reveal health- or disease-modulating properties of Prevotella species in the gut.

The European Commission requested EFSA to update the scientific guidance for the preparation of applications for authorisation of novel foods, previously developed following the adoption of Regulation (EU) 2015/2283 on novel foods. This guidance document provides advice on the scientific information needed to be submitted by the applicant towards demonstrating the safety of the novel food. Requirements pertain to the description of the novel food, production process, compositional data, specifications, proposed uses and use levels and anticipated intake of the novel food. Furthermore, information needed in sections on the history of use of the novel food and/or its source, absorption, distribution, metabolism, excretion, toxicological information, nutritional information and allergenicity is also described. The applicant should integrate and interpret the data presented in the different sections to provide their overall considerations on how the information supports the safety of the novel food under the proposed conditions of use. Where potential health hazards have been identified, they are to be discussed in relation to the anticipated intake of the novel food and the proposed target populations. On the basis of the information provided, EFSA will assess the safety of the novel food under the proposed conditions of use.

The consumer awareness towards healthier diets and the impact of nutrition on health has triggered an increase in the production and commercialization of foods with health claims. The scientific literature classifies these food products as functional foods, with a role in promoting health and preventing diseases, and they had a market share of almost 200 million EUR in 2019. Prebiotics are considered functional foods, referring to substrates that are selectively utilized by host microorganisms conferring a health benefit, as defined by the International Scientific Association for Probiotics and Prebiotics. Several health benefits are associated with the consumption of prebiotics; however, specific requirements must demonstrate the causality between the specific ingredient and the claimed effect. Health claims associated with food products are assessed in the European Union and need to be supported by rigorous scientific evidence before being authorized and permitted on the market. Consumers’ perception of this topic is influenced by the various stakeholders involved. The current work aimed to study the consumers’ perception and interest and to assess the knowledge on the prebiotic concept in Romania. The consumer interest level was quantified by using the web-based data tool Google Trends, and a questionnaire-based investigation was designed. The collected data were analyzed with the help of the SPSS program, and crosstabulation was used to identify the influence of socio-demographic characteristics on diet choice and awareness of prebiotics. A total of 303 persons answered the online applied questionnaire, grouped as young consumers (15–24 years old) and adults (25–64 years old). Even if most responders were familiar with the term of prebiotics (74% of total responders), some results were contradictory regarding their knowledge. The work emphasized the need to carry out educational campaigns and inform consumers on the relationship between certain food ingredients and health outcomes in a clear way and based on a rigorous assessment of the scientific evidence.

Xylo-oligosaccharides are sugar oligomers with 2~7 xylose units considered non-digestible fibers that can be produced from biodegradable and low-cost biomass like wheat straw. An integrated approach consisting of hydrothermal pretreatment, alkaline treatment, enzymatic treatment and the combinations thereof was applied to overcome the recalcitrance structure of the wheat straw and allow selective fractioning into fermentable sugars and xylo-oligosaccharides. The hydrolysates and processed solids were chemically characterized by High-performance liquid chromatography and Ion chromatography, and the results were expressed as function of the severity factor and statistically interpreted. The concentration of fermentable sugars (glucose, xylose, arabinose) was the highest after the combination of alkaline and enzymatic treatment with xylanase (18 g/L sugars), while xylo-oligosaccharides (xylotriose and xylotetraose) were released in lower amounts (1.33 g/L) after the same treatment. Refining experiments were carried out to obtain a purified fraction by using anion and cation exchange chromatography. The polymer adsorber resin MN-502 showed efficient removal of salts, phenols and furan derivatives. However, the xylo-oligosaccharides yields were also slightly reduced. Although still requiring further optimization of the treatments to obtain higher purified oligomer yields, the results provide information on the production of xylo-oligosaccharides and fermentable sugars from wheat straw for potential use in food applications.

This review summarized the current knowledge on probiotics and on the effects that different conditions have under this type of bacteria.The purpose of this review was to evaluate the survival rate/resistance or viability of different probiotic bacteria under several conditions, such as: processing, food composition, storage, freezing, thawing, refrigeration, temperature, oxygen, pH, gastrointestinal environment and package.Nowadays, the demand on probiotic functional foods is increasing rapidly, as the consumers became more aware about the potential health benefits, due to the fact that probiotics help in maintaining the balance and composition of intestinal flora and protect it from pathogens. A daily ingestion of 108–109 CFU ml−1 probiotic microorganisms is crucial in order to be able to demonstrate an effect in our organism, considering the dose and the effect of storage/gastrointestinal environments on the probiotic viability.Microencapsulation of probiotics in different polysaccharides was proven to be an ideal way to preserve and protect the cells from detrimental factors during processing, storage or resistance in the gastrointestinal transit, as many studies demonstrate it.There is a general interest in the improvement of the physical and mechanical stability of the polymers used in probiotics encapsulation, to ensure high population of probiotics not only in food during storage, but also after gastrointestinal digestion. Also, the carrier plays a very important role and should be carefully examined.

Xylo-oligosaccharides (XOS) are considered non-digestible fibers produced mainly from agricultural biomass and are classified as “emerging prebiotic” compounds. Since XOS were shown to promote the growth of bifidobacteria in the gut with potential effects on one’s health, scientists used them as food ingredients. For example, the addition of XOS in bakery products could improve their physicochemical characteristics. The current work aimed to investigate the effect of XOS and glucose addition on wheat flour sourdough fermented with Bifidobacterium animalis subsp. lactis (BB-12) strain in terms of organic acid production. The effect on viscoelastic changes during frozen storage and after the thawing process was also studied. The results showed that the viability of BB-12 increased slightly with the increase in XOS and glucose concentrations, which determined dough acidification due to accumulation of organic acids, that positively influenced the dough’s rheological properties such as a higher elasticity before and after frozen storage. With 10% XOS-addition, the acetic acid quantity reached 0.87 ± 0.03 mg/L, and the highest lactic acid concentration was found in the 10% XOS-enriched doughs, the glucose-enriched doughs and in the control sample (100% wheat dough). The quantity of glucose, maltose, XOS, and xylose decreased until the end of fermentation.