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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]

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]