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Probiotic bacteria, capable of conferring benefits to the host, can present challenges in design, development, scale-up, manufacturing, commercialization, and life cycle management. Strain identification is one of the main quality parameters; nevertheless, this task can be challenging since established methodologies can lack resolution at the strain level for some microorganisms and\or are labor-intensive and time-consuming. Fourier transform infrared spectroscopy (FTIRS) has been largely used for the investigation of pathogenic species in the clinical field, whereas only recently has been proposed for the identification of probiotic strains. Within the probiotic industrial production, bacterial strains can be subjected to stressful conditions that may affect genomic and phenotypic characteristics; therefore, real-time monitoring of all the sequential growth steps is requested. Considering the fast, low-cost, and high-throughput features, FTIRS is an innovative and functional technology for typing probiotic strains from benchtop experiments to large-scale industrial production, allowing the monitoring of stability and identity of probiotic strains. In this study, the discriminatory power of FTIRS was assessed for four Lactiplantibacillus plantarum probiotic strains grown under different conditions, including temperatures (30 and 37◦C) and medium (broth and agar), after consecutive sub-culturing steps. A comparison between the generated spectra with pulsed-field gel electrophoresis (PFGE) profiles was also performed. FTIRS was not only able to distinguish the strains of L. plantarum under different growth conditions but also to prove the phenotypic stability of L. plantarum type strain LP-CT after six growing steps. Regardless of the growth conditions, FTIRS spectra related to LP-CT constituted a unique hierarchical cluster, separated from the other L. plantarum strains. These results were confirmed by a PFGE analysis. In addition, based on FTIRS data, broth cultures demonstrated a higher reproducibility and discriminatory power with respect to agar ones. These results support the introduction of FTIRS in the probiotic industry, allowing for the step-by-step monitoring of massive microbial production while also guaranteeing the stability and purity of the probiotic strain. The proposed novel approach can constitute an impressive improvement in the probiotic manufacturing process. [ABSTRACT FROM AUTHOR]

Fourier transform infrared (FTIR) spectroscopy, a technology traditionally used in chemistry to determine the molecular composition of a wide range of sample types, has gained growing interest in microbial typing. It is based on the different vibrational modes of the covalent bonds between atoms of a given sample, as bacterial cells, induced by the absorption of infrared radiation. This technique has been largely used for the study of pathogenic species, especially in the clinical field, and has been proposed also for the typing at different subspecies levels. The high throughput, speed, low cost, and simplicity make FTIR spectroscopy an attractive technique also for industrial applications, in particular, for probiotics. The aim of this study was to compare FTIR spectroscopy with established genotyping methods, pulsed-field gel electrophoresis (PFGE), whole-genome sequencing (WGS), and multilocus sequence typing (MLST), in order to highlight the FTIR spectroscopy potential discriminatory power at strain level. Our study focused on bifidobacteria, an important group of intestinal commensals generally recognized as probiotics. For their properties in promoting and maintaining health, bifidobacteria are largely marketed by the pharmaceutical, food, and dairy industries. Strains belonging to Bifidobacterium longum subsp. longum and Bifidobacterium animalis subsp. lactis were taken into consideration together with some additional type strains. For B. longum subsp. longum , it was possible to discriminate the strains with all the methods used. Although two isolates were shown to be strictly phylogenetically related, constituting a unique cluster, based on PFGE, WGS, and MLST, no clustering was observed with FTIR. For B. animalis subsp. lactis group, PFGE, WGS, and MLST were non-discriminatory, and only one strain was easily distinguished. On the other hand, FTIR discriminated all the isolates one by one, and no clustering was observed. According to these results, FTIR analysis is not only equivalent to PFGE, WGS, and MLST, but also for some strains, in particular, for B. animalis subsp. lactis group, more informative, being able to differentiate strains not discernible with the other two methods based on phenotypic variations likely deriving from certain genetic changes. Fourier transform infrared spectroscopy has highlighted the possibility of using the cell surface as a kind of barcode making tracing strains possible, representing an important aspect in probiotic applications. Furthermore, this work constitutes the first investigation on bifidobacterial strain typing using FTIR spectroscopy. [ABSTRACT FROM AUTHOR]

Variations in gut microbiota might impact metabolism leading to body weight excess. We assessed the impact of a probiotic supplementation in pediatric obesity on weight, metabolic alterations, selected gut microbial groups, and functionality. Cross-over, double-blind, randomized control trial (BIFI-OBESE trial; NCT03261466). 101 youths (6–18 years, Tanner stage ≥2) with obesity and insulin-resistance on diet were randomized to 2 × 109 CFU/AFU/day of Bifidobacterium breve BR03 (DSM 16604) and B. breve B632 (DSM 24706) (51) or placebo (50) for 8 weeks with a 4-weeks wash-out period. All subjects (M/F 54/47) completed the first 8 weeks, and 82 (M/F 43/39) the last part without adverse events. Mixed-effects models revealed a carry-over effect on many variables in the entire study, narrowing the analysis to the first 8 weeks before the wash-out periods. All subjects improved metabolic parameters, and decreased weight and Escherichia coli counts. Probiotics improved insulin sensitivity at fasting (QUICKI, 0.013 CI95%0.0–0.03) and during OGTT (ISI, 0.654 CI95%-0.11–1.41). Cytokines, GLP1, and target microbial counts did not vary. Of 25 SCFAs, acetic acid and acetic acid pentyl-ester relative abundance remained stable in the probiotics, while increased in the placebo (p < 0.02). A signature of five butanoic esters identified three clusters, one of them had better glucose responses during probiotics. An 8 weeks treatment with B. breve BR03 and B632 had beneficial effects on insulin sensitivity in youths with obesity. Microbiota functionality could influence metabolic answers to probiotics. Long-term studies to confirm and enrich our findings are justified. Tailored probiotic treatments could be an additional strategy for obesity. NCT03261466. [ABSTRACT FROM AUTHOR]

Bergamot whole-fruit powder was analyzed for total polyphenols, flavonoids, flavonols and ascorbic acid content and tested for in vitro and ex vivo antioxidant activity. The flavonoids profile was further characterized via HPLC-DAD-MS/MS and the most abundant flavonoids were quantified. The antimicrobial activity against potentially pathogenic bacteria and the effect on beneficial gut bacteria were determined. Lastly, we evaluated the effects of bergamot extract on endothelial alterations in LPS-stimulated human microvascular endothelial cells (HMEC-1). Our data demonstrated that bergamot powder possesses in vitro and ex vivo antioxidant activity, shows a selective inhibition against pathogenic strains and growth stimulation effects on some beneficial gut bacteria. Moreover, it protects HMEC-1 from LPS-induced activation and dysfunction and reduces the resulting endoplasmic reticulum stress. The relationship between isolated flavonoids and the protective effects are discussed. In conclusion, bergamot whole-fruit powder possesses beneficial health effects that makes it a potentially useful material for the nutraceutical industry. [ABSTRACT FROM AUTHOR]

Highlights: [•] B. pseudocatenulatum B7003 is capable of growing on soya and bean derived milks. [•] B. pseudocatenulatum B7003 can effectively bioconvert bean flavonoids to aglycons. [•] Probiotic starter cultures with flavonoid bioconversion ability are described. [•] Bean fermented milks are functional foods due to their bioactive flavonoids content. [Copyright &y& Elsevier]

This review is aimed at describing the most recent advances in the gut microbiota composition of newborns and infants with a particular emphasis on bifidobacteria. The newborn gut microbiota is quite unstable, whereas after weaning, it becomes more stable and gets closer to the typical adult microbiota. The newborn and infant gut microbiota composition is impaired in several enteric and non-enteric pathologies. The core of this review is the description of the most recent documented applications of bifidobacteria to newborns and infants for their prevention and treatment. Acute diarrhea is the most studied disease for which bifidobacteria are applied with great success, Bifidobacterium longum and Bifidobacterium breve being the most applied species. Moreover, the most recent updates in the use of bifidobacteria for the prevention and treatment of pathologies typical of newborns, such as necrotizing enterocolitis, colics, and streptococcal infections, are presented. In addition, a number of not strictly enteric pathologies have in recent years evidenced a strict correlation with an aberrant gut microbiota in infants, in particular showing a reduced level of bifidobacteria. These diseases represent new potential opportunities for probiotic applications. Among them, allergic diseases, celiac disease, obesity, and neurologic diseases are described in this review. The preliminary use of bifidobacteria in in vitro systems and animal models is summarized as well as preliminary in vivo studies. Only after validation of the results via human clinical trials will the potentiality of bifidobacteria in the prevention and cure of these pathologies be definitely assessed. [ABSTRACT FROM AUTHOR]

The role of a balanced gut microbiota to maintain health and prevent diseases is largely established in humans and livestock. Conversely, in honeybees, studies on gut microbiota perturbations by external factors have started only recently. Natural methods alternative to chemical products to preserve honeybee health have been proposed, but their effect on the gut microbiota has not been examined in detail. This study aims to investigate the effect of the administration of a bacterial mixture of bifidobacteria and Lactobacillaceae and a commercial product HiveAliveTM on honeybee gut microbiota. The study was developed in 18 hives of about 2500 bees, with six replicates for each experimental condition for a total of three experimental groups. The absolute abundance of main microbial taxa was studied using qPCR and NGS. The results showed that the majority of the administered strains were detected in the gut. On the whole, great perturbations upon the administration of the bacterial mixture and the plant-based commercial product were not observed in the gut microbiota. Significant variations with respect to the untreated control were only observed for Snodgrassella sp. for the bacterial mixture, Bartonella sp. in HiveAliveTM and Bombilactobacillus sp. for both. Therefore, the studied approaches are respectful of the honeybee microbiota composition, conceivably without compromising the bee nutritional, social and ecological functions. [ABSTRACT FROM AUTHOR]

The human intestinal microbiota, establishing a symbiotic relationship with the host, plays a significant role for human health. It is also well known that a disease status is frequently characterized by a dysbiotic condition of the gut microbiota. A probiotic treatment can represent an alternative therapy for enteric disorders and human pathologies not apparently linked to the gastrointestinal tract. Among bifidobacteria, strains of the species Bifidobacterium breve are widely used in paediatrics. B. breve is the dominant species in the gut of breast-fed infants and it has also been isolated from human milk. It has antimicrobial activity against human pathogens, it does not possess transmissible antibiotic resistance traits, it is not cytotoxic and it has immuno-stimulating abilities. This review describes the applications of B. breve strains mainly for the prevention/treatment of paediatric pathologies. The target pathologies range from widespread gut diseases, including diarrhoea and infant colics, to celiac disease, obesity, allergic and neurological disorders. Moreover, B. breve strains are used for the prevention of side infections in preterm newborns and during antibiotic treatments or chemotherapy. With this documentation, we hope to increase knowledge on this species to boost the interest in the emerging discipline known as "therapeutic microbiology". [ABSTRACT FROM AUTHOR]

In order to meet the increasing demand for food quality and safety, the control of pathogenic microorganisms from “farm to fork” is a continuous challenge. This challenge has become more important due to changes in animal production, product processing and distribution, new food habits, higher numbers of consumers at risk for infection and increased awareness. This review is focused on the use of protective and probiotic cultures as “natural” intervention measures to control and prevent the transmission of pathogens along the food chain and on the most used technologies to produce these cultures at the large scale. [ABSTRACT FROM AUTHOR]

Abstract: With the ban of dietary antimicrobial agents, the use of probiotics, prebiotics and synbiotics has attracted a great deal of attention in order to improve intestinal health and control food-borne pathogens, which is an important concern for the production of safe meat and meat products. Recently, Campylobacter jejuni has emerged as a leading bacterial cause of food-borne gastroenteritis in humans, and epidemiological evidences indicate poultry and poultry products as the main source of human infection. This work aimed at the development of a synbiotic mixture capable of modulating the gut microbiota of broiler chickens to obtain an increase of the beneficial bacteria (i.e. bifidobacteria, lactobacilli) and a competitive reduction of C. jejuni. The prebiotic compound used in the mixture was chosen after an in vivo trial: a fructooligosaccharide and a galactooligosaccharide were separately administered to broilers mixed with normal feed at a concentration of 0.5% and 3%, respectively. Quantitative PCR on DNA extracted from fecal samples revealed a significant (p<0.05) increase of Bifidobacterium spp. in broilers treated with the galactooligosaccharide, coupled to a decrease (p<0.05) of Campylobacter spp. The galactooligosaccharide was then combined with a probiotic Bifidobacterium strain (B. longum subsp. longum PCB133), possessing in vitro antimicrobial activity against C. jejuni. The strain was microencapsulated in a lipid matrix to ensure viability into the feed and resistance to stomach transit. Finally, the synbiotic mixture was administered to broiler chickens for 14days mixed with normal feed in order to have an intake of 109 CFU of PCB133/day. Bifidobacterium spp., Lactobacillus spp., Campylobacter spp., B. longum subsp. longum and C. jejuni were quantified in fecal samples. PCB133 was recovered in feces of all animals. C. jejuni concentration in poultry feces was significantly (p<0.05) reduced in chickens administered with the synbiotic mixture. This study allowed to highlight the positive effect of the synbiotic approach for C. jejuni reduction in broiler chickens, which is of fundamental importance for the safety of poultry meat consumers. [Copyright &y& Elsevier]

The capability of ten commercial fibers of selectively stimulating the growth of four Bifidobacterium strains were studied with the purpose of developing a synbiotic product for infants. Two galacto-oligosaccharides (GOS), one fructo-oligosaccharide (sc-FOS), four inulins with different polymerization degree (DP), a gluco-oligosaccharide, an arabinogalactan and a hydrolyzed guar gum were used (10 gl −1 ). The prebiotic score was calculated comparing the capability of the fibers of stimulating the growth of bifidobacteria compared to infant pathogens. GOS, sc-FOS, low DP inulin (oligofructose) and the gluco-oligosaccharide could stimulate growth. However, the fibers showing the highest prebiotic score were oligofructose (Orafti ® HIS), sc-FOS (Actilight ® 950P) and the GOS Vivinal ® . Lyophilized strain survival in simulated gastro-intestinal conditions was also assayed to define suitable ways of administration. Survival in gastric juice at pH 2.5 was poor, whereas it was higher at pH 4, a value closer to newborn pH. Microencapsulation in a lipid matrix ensured strain survival also at pH 2.5. Survival to 1 gl −1 bile salts was acceptable. The results allowed to conclude that Bifidobacterium breve B632 strain, in a lyophilized or microencapsulated form, has the potential for use in synbiotic products targeted to infants coupled to a mixture of GOS and FOS or oligofructose. [ABSTRACT FROM AUTHOR]

Abstract: Campylobacteriosis is at present the most frequent zoonosis in humans and the main source is poultry meat contaminated by Campylobacter jejuni. An alternative and effective approach to antibiotic administration to livestock to reduce bacterial contamination is the use of probiotics, which can help to improve the natural defence of animals against pathogenic bacteria. In this study 55 lactic acid bacteria and bifidobacteria were screened for desirable properties for their application as probiotics against Campylobacter in poultry. All bacteria were examined for their antimicrobial activity against three C. jejuni strains. Strains exhibiting the highest anti-Campylobacter activity were examined for their survival in the gastro intestinal tract (low pH and presence of bile salts) and food/feed processing conditions (high temperature, high NaCl concentration and starvation) and basic safety aspects such as antibiotic susceptibility and hemolytic activity were studied. On the basis of these activities, two strains, namely Lactobacillus plantarum PCS 20 and Bifidobacterium longum PCB 133, were chosen for an in vivo trial in poultry. They were separately administered to healthy chickens in order to evaluate their capability of colonizing the GI tract of poultry and to estimate their effect on C. jejuni population. The results evidenced that L. plantarum PCS 20 was not present in poultry feces at detectable concentration, whereas B. longum PCB 133 significantly increased after two weeks of daily administration and its amount was still high after a wash-out period of 6days. In the same period, C. jejuni concentration in poultry feces was significantly reduced in chickens administered with B. longum PCB 133. Therefore, B. longum PCB 133, possessing interesting probiotic properties and a marked anti-Campylobacter activity both in vitro and in vivo, is an excellent candidate for being employed as additives to feed for poultry for the reduction of food-borne campylobacteriosis in humans. [Copyright &y& Elsevier]