Examination of the effect of reduction of probiotic species Lactobacillus due to broad spectrum antibiotic treatment on oral tolerance

Antibiotic usage is on the rise in industrialized countries and as a result the prevalence of autoimmune and atopic diseases has risen. The use of antibiotics is connected to a depletion of the microflora located within the gastrointestinal tract. The microflora contains a variety of different bacterial species, including some that are probiotic species, Lactobacilli and Bifidobacteria, which have a beneficial effect on the host. Probiotic species of bacteria are important for immune function due to their ability to regulate oral tolerance, a state of unresponsiveness to antigens that have been introduced orally to the host. The goal of this study was to assess the effect of broad spectrum antibiotic treatment on the probiotic species Lactobacilli and the resulting effect on the induction of oral tolerization to the antigen ovalbumin.Department of BiologyThesis (M.S.

The effect of microorganisms on processes of weathering primary minerals

Microflora and microorganism effects on weathering, decomposition, and secondary synthesis of primary mineral

Research on long term biological isolation of primates and mice. Volume 4 - The literature search, appendix M Final report

Literature search for effects of intestinal microflora on host organism

Investigation of the Influence of Antioxidant Compositions on Development of Microbiological Spoilage in Storage of Fruits

The studies are devoted to the scientific grounding of expedience of after-harvest processing by antioxidant compositions for preventing the development of pathogenic microflora on fruit surfaces during a long storage. For the studies were used apple fruits of the varieties Aidared, Golden Dushesse, Renet Simirenka, pear fruits of the varieties Victoria, Crimea Raisin and Cure, plum fruits of the varieties Voloshka, Stanley and Italian Ugorka. Fruits were processed by immersion in the following antioxidant compositions: ACM is a mixture of dimethyl sulfoxide, ionol and polyethylene glycols; AARL – mixture of ascorbic acid, routin and lecithin; DL – mixture of dimethyl sulfoxide, ionol and lecithin. Fruits, processed by water, were used as a control. Exposition - 10 seconds. Storage was carried out at the temperature 0±1 ºС, relative air humidity 90–95 %. It was established that in the period of fruits laying for storage, the mean amount of epiphyte microflora was fixed on surfaces of plump and pear fruits of the mean ripening term. In the variety composition of epiphyte microflora prevailed spores of mesophyl aerobic and facultative-anaerobic microorganisms. Their mean number on apple fruits surface was 9,6·103 CCU/g, pear fruits – 10,6 103 CCU/g, plump fruits – 18·103CCCU/g. AOC processing of all types of fruits essentially decreased the speed of both MAFAnM and micromycetes growth. It was demonstrated that the used compositions in 2…3,5 times decreased the level of day losses from microbiological spoilage during the whole storage period. The most positive effect was received at using compositions, based on dystinol and lecithin. Multifactor analysis determined that the level of day losses from microbiological spoilage was mainly influenced by factors of raw material variety features (factor A) and antioxidant compositions processing (factor D). The shares of influence are 24 and 21 % respectively

Antagonistic Effect of Intestinal Bacteria from the Microflora of Holoxenic (Conventional) Piglets, Against Clostridium Perfringens in the Digestive Tract of Gnotoxenic Mice and Gnotoxenic Piglets

Antagonistic effect of piglet microflora against Clostridium perfringens was studied in germfree mice, to isolate bacterial strains responsible for this colonization resistance. The 1:100 dilution of the feces of a 2 day-old conventional piglet, given per os to germfree mice already harboring C. perfringens, led to the elimination of C. perfringens. From this piglet flora, 8 bacterial strains were selected, belonging to the genera Bacteroides, Clostridium, Eubacterium, Bifidobacterium, Lactobacillus and a strain belonging to the class of Mollicutes. When the 8 strains were given to germfree mice 3 days after C. perfringens inoculation, they led to rapid elimination of C. perfringens from feces. Sixteen other mixtures of 2 to 7 strains were similarly tested, but none was able to fully antagonize C. perfringens. When the 8 strains were given per os to germfree piglets after C. perfringens inoculation, they led to the rapid elimination of C. perfringens from pig feces, and to a quick recovery from diarrhea. This study led to the identification of a simplified fraction of gut microflora, able to exert a barrier effect against C. perfringens comparable to the entire flora of the piglet. This study suggests that gnotoxenic mice can be a suitable model for simplifying the flora responsible for a given effect in another host, animal or human

Disease suppressive soilless culture systems; characterisation of its microflora

The trend in glasshouse horticulture has always been to start culture systems as aseptic as possible. However, several root diseases still cause problems under these conditions. The present paper shows the importance of the microflora to suppress Pythium aphanidermatum, a fungal root pathogen which is a serious threat in cucumber. Introduced single antagonists as well as the indigenous microflora suppressed pythium root and crown rot. Pseudomonas fluorescens, Streptomyces griseoviridis, Pythium oligandrum, and 2 isolates of Trichoderma harzianum reduced the disease occurrence by 60 ␘r more in several, but not all, of the experiments. The indigenous microflora showed a very constant disease suppression of 50 to 100 &Eth;This was tested in experiments where P. aphanidermatum was added to sterilised and non-sterilised rockwool, and to sterilised rockwool that had been recolonised with the original microflora. Suppressiveness correlated with the number of filamentous actinomycetes present in the nutrient solution in the rockwool slabs. If a beneficial microflora is present in the cropping system, it should not be disturbed or eradicated by treatments such as disinfection of the recirculated nutrient solution. Therefore, the effects of different disinfection procedures on the composition of the microflora were compared. Numbers of filamentous actinomycetes in the nutrient solution in the tank after the disinfection treatment were highest without disinfection, intermediate after slow filtration, and lowest after UV treatment. Numbers of actinomycetes in the slabs, i.e. around the roots, were not distinctly different between the treatments. The implication of potential shifts in the microbial populations due to certain treatments for the disease development is not known. Increased knowledge on the beneficial microflora and the treatments that influence the composition of such a microflora, will stimulate the exploitation of microbially balanced and optimised soilless culture systems

Microflora in soils of desert regions

Desert soil samples, collected using aseptic techniques, are low in organic matter and cation exchange capacity. Aerobic and microaerophilic bacteria are most abundant, next are algae and molds. Chemical and physical properties are determined by standard procedures, including the Kjeldahl method and the use of Munsell soil color charts

Living on apples - anthropogenic influence on microbial communities of apple fruits

Microbial communities on non-processed foods are complex with unknown effects on food quality and human health. It is generally assumed that the ecology of the microflora associated with apples reflects the environment of the orchard, handling, harvesting, and storage. We performed a comparative field trial to assess how anthropogenic factors, such as organic and conventional farming practices, influence the microbial community of apple fruits. Apples are an economically important crop in Switzerland. In 2004, we harvested apple fruits cv. Golden Delicious of five pairs of organic/ conventional farms at five different locations in Switzerland. We combined classical microbiological methods and genetic tools to characterize the cultivable and uncultivable microflora of apple fruits. Morphologically distinct mold and yeast colonies were recovered from apple fruit surface (epiphytes) or from underneath the skin (endophytes) and recorded on nutrient agar. We also started to develop culture-independent molecular DNA-techniques (e.g. PCR of internal transcribed spacer region, ITS) for species identification and fungal community studies. Several white and red/pink yeasts and yeastlike fungi were the predominant epiphytes. Morphologically different molds formed almost exclusively the endophytic microflora. The yeast-like fungi were more abundantly and more frequently found on organic apple fruits whereas red/pink yeasts prevailed on conventional fruits. We found higher numbers of endophytic molds and more morphological types in organic fruits. These results suggest that the microbial community of apple fruits adapts to the farming practice, a feature which might be useful for authenticity and food quality

Flavanol monomer-induced changes to the human faecal microflora

We have investigated the bacterial-dependent metabolism of ( − )-epicatechin and (+)-catechin using a pH-controlled, stirred, batch-culture fermentation system reflective of the distal region of the human large intestine. Incubation of ( − )-epicatechin or (+)-catechin (150 mg/l or 1000 mg/l) with faecal bacteria, led to the generation of 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone, 5-phenyl-γ-valerolactone and phenylpropionic acid. However, the formation of these metabolites from (+)-catechin required its initial conversion to (+)-epicatechin. The metabolism of both flavanols occurred in the presence of favourable carbon sources, notably sucrose and the prebiotic fructo-oligosaccharides, indicating that bacterial utilisation of flavanols also occurs when preferential energy sources are available. (+)-Catechin incubation affected the growth of select microflora, resulting in a statistically significant increase in the growth of the Clostridium coccoides–Eubacterium rectale group, Bifidobacterium spp. and Escherichia coli, as well as a significant inhibitory effect on the growth of the C. histolyticum group. In contrast, the effect of ( − )-epicatechin was less profound, only significantly increasing the growth of the C. coccoides–Eubacterium rectale group. These potential prebiotic effects for both (+)-catechin and ( − )-epicatechin were most notable at the lower concentration of 150 mg/l. As both ( − )-epicatechin and (+)-catechin were converted to the same metabolites, the more dramatic change in the growth of distinct microfloral populations produced by (+)-catechin incubation may be linked to the bacterial conversion of (+)-catechin to (+)-epicatechin. Together these data suggest that the consumption of flavanol-rich foods may support gut health through their ability to exert prebiotic actions

Efficacy of Probiotics for Reducing the Incidence of Lameness in Broilers Grown on Wire Flooring

Growing broilers on wire flooring provides an excellent experimental model for reproducibly triggering significant levels of lameness. In Pilot Study #1 using broilers from Line C grown on wire flooring, adding the Biomin probiotic PoultryStar® to the feed reduced the percentage of lameness by half when compared with broilers that received the control diet alone. In Pilot Study # 2 using broilers from Line B grown on wire flooring, adding the PoultryStar® probiotic reduced the percentage of lameness to 8% when compared with 28% lameness in broilers that received the control diet alone. The objective of this study was to conduct a replicated experiment to determine if probiotics consistently reduced the incidence of lameness in broilers reared on wire flooring. Male broiler chicks from Cobb-Vantress Line B were placed at 1 day of age in pens having flat wire flooring within environmental chambers 1 through 10 inside the Poultry Environmental Research Lab at the University of Arkansas Poultry Research Farm. On day 14, birds were culled to 50 per pen, yielding a density of 1ft²/chick. A corn and soybean meal-based diet formulated to meet minimum National Research Council standards (1994) for all ingredients was provided ad libitum as the control feed. Broilers in chambers 1, 3, 5, 7 and 9 were provided the control feed while chambers 2, 4, 6, 8 and 10 were provided the same feed mixed with the probiotic throughout the experiment (50 lbs of control feed blended with 12.5 g PoultryStar® probiotic). The birds in all pens were walked and observed for lameness every two days starting on day 15 and continuing until the end of the experiment on day 56. Birds unable or unwilling to walk were diagnosed as clinically lame and humanely euthanized with CO2 gas. They were then necropsied to assess sub-clinical lesion incidences including femoral head separation, femoral head transitional degeneration, femoral head necrosis, tibial head necrosis, and tibial dyschondroplasia. Findings from the study indicate that for broilers grown on wire flooring, diets containing the probiotic PoultryStar® consistently reduced the incidence of lameness when compared with birds fed the control diet alone