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Bifidobacterium Spp. (bifidobacterium + spp)
Selected AbstractsPreliminary investigation of the combined effect of heat treatment and incubation temperature on the viability of the probiotic micro-organisms in freshly made yogurtINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 1 2006A M MORTAZAVIAN The combined effects of heat treatment and incubation temperature were studied on the viability and fermentation time of probiotics in ABY 1 probiotic yogurt (Lactobacillus acidophilus, Bifidobacterium spp. and yogurt bacteria). Three levels of heat treatment (85°C for 30 min, 95°C for 5 min and 95°C for 15 min) and three levels of incubation temperature (37, 40 and 44°C) were selected. At the end of fermentation, the maximum viability of probiotics (for both L. acidophilus and Bifidobacterium spp.) was observed when the milk was heated at 95°C for 15 min and incubated at 37°C. Incubation time was only affected by the incubation temperature and, at 37°C, the longest incubation time of about 6 h was needed to achieve the highest viable counts of L. acidophilus and Bifidobacterium spp. [source] Effect of packaging materials and dissolved oxygen on the survival of probiotic bacteria in yoghurtINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 6 2004Akshat Talwalkar Summary The effects of packaging materials on the dissolved oxygen and the survival of the probiotic bacteria in yoghurt were studied. Oxygen adapted and non-oxygen adapted strains of Lactobacillus acidophilus and Bifidobacterium spp. were incorporated in yoghurts, which were packaged in oxygen permeable high-impact polystyrene (HIPS), oxygen-barrier material (NupakTM) and NupakTM with an oxygen scavenging film (Zero2TM). During storage the dissolved oxygen increased steadily in HIPS packaged yoghurt whereas it remained low in yoghurts packaged in NupakTM and Zero2TM. In all yoghurts, no significant decreases were observed in the viability of either oxygen adapted or non-oxygen adapted cells of L. acidophilus and Bifidobacterium spp. Thus, although the dissolved oxygen in yoghurt can be influenced by the type of packaging material, it may not affect the survival of probiotic bacteria in yoghurts. [source] The persistence of bifidobacteria populations in a river measured by molecular and culture techniquesJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2009X. Bonjoch Abstract Aims:, To determine relative to faecal coliforms (FC) and sulfite-reducing clostridia (SRC), the environmental persistence of natural populations of Bifidobacterium spp. enumerated by culturing and quantitative polymerase chain reaction (q-PCR). Methods and Results:, Dialysis tubing containing river supplemented with overnight cultures of Bifidobacterium adolescentis (BA) and Bifidobacterium dentium (BD) or urban wastewater were suspended in a river for up to 10 days. At intervals, the contents of each dialysis tube were assayed using q-PCR assays for BA and BD, and selective culture media for FC, SRC, total bifidobacteria (TB), sorbitol-fermenting bifidobacteria (SFB) and cultivable BA. Mean summer T90 values were 251 h for SRC, 92 h for FC, 48 h for BA and BD by q-PCR, and 9 h for TB. Conclusions:,Bifidobacterium spp. was the population with the lowest persistence, showing seasonal differences in T90 when measured by culture techniques or by q-PCR. This difference in relative persistence is because of a longer persistence of molecular targets than cultivable cells. Significance and Impact of the Study:, The persistence of a viable bifidobacteria cells is shorter, but the longest persistence of molecular targets. This factor could be used for origin the faecal pollution in water for the development of microbial source tracking (MST). [source] Growth, Viability and Activity of Bifidobacterium spp. in Skim Milk Containing PrebioticsJOURNAL OF FOOD SCIENCE, Issue 7 2002F.A. Bruno ABSTRACT: Growth, activity and mean doubling time (Td) of five Bifidobacterium species in the presence of four types of prebiotics, and concentrations of acetic and lactic acids were determinted during fermentation and after 4 weeks of refrigerated storage. The Td was lowest for B. animalis with raftilose and inulin. Retention of viability of bifidobacteria was greatest with hi-amylose corn starch (hi-maize). The average pH of skim milk at the end of 4 wks storage averaged 4.34 (for B. animalis with raftilose) to 4.07 (for B. longum with inulin). The highest levels of acetic acid and lactic acid were produced by B. pseudolongum with lactulose and B. infantis with lactulose, respectively. [source] Bifidobacterium and Lactobacillus DNA in the human placentaLETTERS IN APPLIED MICROBIOLOGY, Issue 1 2009R. Satokari Abstract Aims:, Bifidobacteria and lactobacilli are part of the human normal intestinal microbiota and may possibly be transferred to the placenta. It was hypothesized that intestinal bacteria or their components are present in the placenta and that the foetus may be exposed to them. We investigated the presence of bifidobacteria and lactobacilli and their DNA in the human placenta. Methods and Results:, We studied 34 human placentae (25 vaginal and nine caesarean deliveries) for the presence Bifidobacterium spp. and Lactobacillus rhamnosus. Cultivation was used for the detection of viable cells and genus and species-specific PCR for the detection of DNA. No bifidobacteria or lactobacilli were found by cultivation. Bifidobacterial DNA was detected in 33 and L. rhamnosus DNA in 31 placenta samples. Conclusions:, DNA from intestinal bacteria was found in most placenta samples. The results suggest that horizontal transfer of bacterial DNA from mother to foetus may occur via placenta. Significance and Impact of the Study:, Bacterial DNA contains unmethylated CpG oligodeoxynucleotide motifs which induce immune effects. Specific CpG motifs activate Toll-like receptor 9 and subsequently trigger Th-1-type immune responses. Although the newborn infant is considered immunologically immature, exposure by bacterial DNA may programme the infant's immune development during foetal life earlier than previously considered. [source] Determination of survival, identity and stress resistance of probiotic bifidobacteria in bio-yoghurtsLETTERS IN APPLIED MICROBIOLOGY, Issue 3 2006V.S. Jayamanne Abstract Aims:, To determine the level of bifidobacteria in bio-yoghurts in the UK, identify the species, and compare the resistance of common Bifidobacterium spp. to acidity and oxidative stress. Methods and Results:, A storage trial of bio-yoghurts was carried out to determine the level and survival of bifidobacteria. The 16S rRNA gene targeted PCR was used to identify the species. Acid tolerance was determined by introducing the organisms to pH-adjusted skimmed milk and enumerating during storage at 4°C. Oxidative stress resistance was determined using the H2O2 disc diffusion assay technique. Nine of 10 bio-yoghurts contained bifidobacteria at levels >106 CFU g,1 at the time of purchase. The viability of the organism decreased during storage and on expiry only five products retained viability >106 CFU g,1 while two others were very close to the target population. Bifidobacterium animalis ssp. lactis showed superior survival abilities and stress tolerance compared with Bifidobacterium longum, Bifidobacterium breve, Bifidobacterium bifidum, Bifidobacterium adolescentis and Bifidobacterium longum biotype infantis. Conclusions:,Bifidobacterium animalis ssp. lactis, the only Bifidobacterium spp. found in bio-yoghurts, had the greatest resistance to acidity and oxidative stress. Significance and Impact of the Study:, The technological properties of B. animalis ssp. lactis make it suitable for inclusion in bio-yoghurts although its putative health benefits need further investigation. [source] Bifidobacterium -selective isolation and enumeration from chicken caeca by a modified oligosaccharide antibiotic-selective agar mediumLETTERS IN APPLIED MICROBIOLOGY, Issue 4 2005S.N. Thitaram Abstract Aims:, To determine the efficacy and selectivity of an acidified, antibiotic-selective, oligosaccharide-containing media for enumerating Bifidobacterium spp. from chicken caeca samples. Methods and Results:, Transoligosaccharide propionate agar medium (TOS) modified by addition of mupirocin (50 ,g ml,1) and glacial acetic acid (1%, v/v), did not inhibit the growth of bifidobacteria compared with the control media yet inhibited the growth of Lactobacillus acidophilus, Lactobacillus gallinarum, Lactobacillus helveticus and Streptococcus gordonii. Conclusions:, Addition of mupirocin (50 ,g ml,1) and glacial acetic acid (1%, v/v) to TOS (TOS-AM50), is an effective selective medium for isolation and enumeration of Bifidobacterium spp. from chicken caeca samples. Significance and Impact of the Study:, The development of an intestinal bifidobacteria-selective media contributes to the study of probiotics and prebiotics in poultry and potentially other species. [source] Bifidobacterium carbohydrases-their role in breakdown and synthesis of (potential) prebioticsMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 1 2008Lambertus A. M. van den Broek Abstract There is an increasing interest to positively influence the human intestinal microbiota through the diet by the use of prebiotics and/or probiotics. It is anticipated that this will balance the microbial composition in the gastrointestinal tract in favor of health promoting genera such as Bifidobacterium and Lactobacillus. Carbohydrates like non-digestible oligosaccharides are potential prebiotics. To understand how these bacteria can grow on these carbon sources, knowledge of the carbohydrate-modifying enzymes is needed. Little is known about the carbohydrate-modifying enzymes of bifidobacteria. The genome sequence of Bifidobacterium adolescentis and Bifidobacterium longum biotype longum has been completed and it was observed that for B. longum biotype longum more than 8% of the annotated genes were involved in carbohydrate metabolism. In addition more sequence data of individual carbohydrases from other Bifidobacterium spp. became available. Besides the degradation of (potential) prebiotics by bifidobacterial glycoside hydrolases, we will focus in this review on the possibilities to produce new classes of non-digestible oligosaccharides by showing the presence and (transglycosylation) activity of the most important carbohydrate modifying enzymes in bifidobacteria. Approaches to use and improve carbohydrate-modifying enzymes in prebiotic design will be discussed. [source] The complex oral microflora of high-risk individuals and groups and its role in the caries processCOMMUNITY DENTISTRY AND ORAL EPIDEMIOLOGY, Issue 4 2005David Beighton Abstract , The involvement of the oral biofilm in the caries process requires re-evaluation. The essential role of mutans streptococci (Streptococcus mutans and Streptococcus sobrinus) in the caries process is not proven. Acid production by dental plaque is not dependent upon the presence of mutans streptococci; caries occurs in the absence of these species and their presence does not necessarily indicate caries activity. Other oral bacteria, non-mutans streptococci, Actinomyces spp. and Bifidobacterium spp., are acidogenic and aciduric. They outnumber mutans streptococci in dental plaque, and there are data which support a role for these bacteria in the initiation and progression of caries. Molecular studies demonstrate the great diversity and complexity of the flora associated with caries. Many taxa identified have not been cultured and the role of these taxa is not known. We have, in mutans streptococci, good markers of disease but not necessarily the aetiological agents of the disease. Considerably more research is required to investigate the transition of tooth surfaces from being intact and sound to the white spot lesion stage. A combination of conventional and molecular approaches are required to elucidate the involvement of an individual taxon and of microbial populations with particular traits in the caries process. [source] | |||||||||||||