53 resultados para oligofructose
Resumo:
The aim of this study was to verify the effect of inulin and oligofructose on the physicochemical, microbiological and sensory characteristics of symbiotic dairy beverages. Four formulations were made: 1) a control (C); 2) a sample with added Lactobacillus paracasei (P); 3) a sample with added L. paracasei and inulin (PI); and 4) a sample with added L. paracasei and oligofructose (PO). The probiotic population, pH, and acidity of the products were evaluated once a week for 21 days while refrigerated (5 +/- 1 degrees C). Possible contaminating microorganisms (coliforms, E. coli, and Salmonella spp.) were investigated after three days of storage. Sensorial acceptance and purchase intention were evaluated seven days after manufacture. Dairy beverages presented with L. paracasei populations above 8.50 log CFU/mL during the whole storage period. Significantly (p<0.05) lower pH values were observed in P and PI, and higher acidity values were found in all formulations throughout storage. The dairy beverages were considered to be a promising matrix for the probiotic microorganism L. paracasei. The prebiotic additions (inulin and oligofructose) did not interfere with the overall acceptance and intention to purchase the beverages.
Resumo:
Twelve dairy heifers were used to examine the clinical response of an alimentary oligofructose overload. Six animals were divided into 3 subgroups, and each was given a bolus dose of 13, 17, or 21 g/kg of oligofructose orally. The control group (n = 6) was sham-treated with tap water. Signs of lameness, cardiovascular function, and gastrointestinal function were monitored every 6 h during development of rumen acidosis. The heifers were euthanized 48 and 72 h after administration of oligofructose. All animals given oligofructose developed depression, anorexia, and diarrhea 9 to 39 h after receiving oligofructose. By 33 to 45 h after treatment, the feces returned to normal consistency and the heifers began eating again. Animals given oligofructose developed transient fever, severe metabolic acidosis, and moderate dehydration, which were alleviated by supportive therapy. Four of 6 animals given oligofructose displayed clinical signs of laminitis starting 39 to 45 h after receiving oligofructose and lasting until euthanasia. The lameness was obvious, but could easily be overlooked by the untrained eye, because the heifers continued to stand and walk, and did not interrupt their eating behavior. No positive pain reactions or lameness were seen in control animals. Based on these results, we conclude that an alimentary oligofructose overload is able to induce signs of acute laminitis in cattle. This model offers a new method, which can be used in further investigation of the pathogenesis and pathophysiology of bovine laminitis.
Resumo:
Histopathology of the dermo-epidermal junction in the lamellar region of front claws was examined in 6 dairy heifers given an alimentary oligofructose overload and compared with sections from a control group of 6 heifers. Four of the 6 heifers administered oligofructose developed clinical signs of acute laminitis before they were euthanized. Postmortem samples from front claws were processed for histology. Eleven histopathologic characteristics were selected from the existing literature and used in a blinded evaluation of sections. In total, 104 front claw samples, including 8 samples from 2 cows having spontaneously occurring acute laminitis, were evaluated histologically using hematoxylin and eosin as well as periodic acid-Schiff staining. The major morphological features associated with oligofructose-induced acute clinical laminitis were stretching of lamellae, dermal edema, hemorrhage, changes in basal cell morphology, presence of white blood cells in dermis, and signs of basement membrane detachment. Changes at the lamellar junction of claw tissue affected by oligofructose-induced clinical laminitis resembled tissue from the 2 cows suffering from spontaneous acute clinical laminitis, and generally were consistent with existing descriptions of laminitis histopathology. Important exceptions to existing descriptions in the literature were stretching of lamellae and basement membrane changes. Not previously described, we considered these early signs of acute laminitis. In conclusion, this study documents that oligofructose-induced clinical laminitis is associated with histopathological changes at the lamellar interface. A weakened dermo-epidermal junction is a possible intermediate stage in the pathophysiology of bovine sole ulceration at the typical site.
Resumo:
In the horse, carbohydrate overload is thought to play an integral role in the onset of laminitis by drastically altering the profile of bacterial populations in the hindgut. The objectives of this study were to develop and validate microbial ecology methods to monitor changes in bacterial populations throughout the course of experimentally induced laminitis and to identify the predominant oligofructose-utilizing organisms. Laminitis was induced in five horses by administration of oligofructose. Faecal specimens were collected at 8 h intervals from 72 h before to 72 h after the administration of oligofructose. Hindgut microbiota able to utilize oligofructose were enumerated throughout the course of the experiment using habitat-simulating medium. Isolates were collected and representatives identified by 16S rRNA gene sequencing. The majority of these isolates collected belonged to the genus Streptococcus, 91% of which were identified as being most closely related to Streptococcus infantarius ssp. coli. Furthermore, S. infantarius ssp. coli was the predominant oligofructose-utilizing organism isolated before the onset of lameness. Fluorescence in situ hybridization probes developed to specifically target the isolated Streptococcus spp. demonstrated marked population increases between 8 and 16 h post oligofructose administration. This was followed by a rapid population decline which corresponded with a sharp decline in faecal pH and subsequently lameness at 24-32 h post oligofructose administration. This research suggests that streptococci within the Streptococcus bovis/equinus complex may be involved in the series of events which precede the onset of laminitis in the horse.
Resumo:
In the article 'Fluorescence in situ hybridization analysis of hindgut bacteria associated with the development of equine laminitis' (Milinovich et al., 2007), it is found that with reference to Horse 1, the histological signs of laminitis were first observed at 12 h post-oligofructose administration, and not 30 h as was indicated in the Results section under the subheading 'Induction of Laminitis' and in Fig. 1.
Resumo:
Batch and continuous culture anaerobic fermentation systems, inoculated with human faeces, were utilised to investigate the antimicrobial actions of two probiotics, Lactobacillus plantartan 0407, combined with oligofructose and Bifidobacterium bifidum Bb12, combined with a mixture of oligofructose and xylo-oligosaccharides (50:50 w/w) against E coli and Campylobacter jejuni. In batch fermenters, both E coli and C jejuni were inhibited by the synbiotics, even when the culture pH was maintained at around neutral. In continuous culture C jejuni was inhibited but the synbiotic failed to inhibit E coli. Although no definitive answer in addressing the mechanisms underlying antimicrobial activity was derived, results suggested that acetate and lactate directly were conferring antagonistic action, rather than as a result of lowering culture pH. In the course of the study culturing and fluorescent in situ hybridisation (FISH) methodologies for the enumeration of bacterial populations were compared. Bifidobacterial populations were underestimated using plating techniques, suggesting the non-culturability of certain bifidobacterial species. (C) 2003 Elsevier Ltd. All rights reserved.
Resumo:
Background: Animal studies suggest that prebiotics and probiotics exert protective effects against tumor development in the colon, but human data supporting this suggestion are weak. Objective: The objective was to verify whether the prebiotic concept (selective interaction with colonic flora of nondigested carbohydrates) as induced by a synbiotic preparation-oligofructose-enriched inulin (SYN1) + Lactobacillus rhamnosus GG (LGG) and Bifidobacterium lactis Bb12 (BB12)-is able to reduce the risk of colon cancer in humans. Design: The 12-wk randomized, double-blind, placebo-controlled trial of a synbiotic food composed of the prebiotic SYN1 and probiotics LGG and BB12 was conducted in 37 colon cancer patients and 43 polypectomized patients. Fecal and blood samples were obtained before, during, and after the intervention, and colorectal biopsy samples were obtained before and after the intervention. The effect of synbiotic consumption on a battery of intermediate biomarkers for colon cancer was examined. Results: Synbiotic intervention resulted in significant changes in fecal flora: Bifidobacterium and Lactobacillus increased and Clostridium perfringens decreased. The intervention significantly reduced colorectal proliferation and the capacity of fecal water to induce necrosis in colonic cells and improve epithelial barrier function in polypectomized patients. Genotoxicity assays of colonic biopsy samples indicated a decreased exposure to genotoxins in polypectomized patients at the end of the intervention period. Synbiotic consumption prevented an increased secretion of interleukin 2 by peripheral blood mononuclear cells in the polypectomized patients and increased the production of interferon gamma in the cancer patients. Conclusions: Several colorectal cancer biomarkers can be altered favorably by synbiotic intervention.
Resumo:
The objective of this article is to review existing studies concerning the effects of probiotics and prebiotics on serum cholesterol concentrations, with particular attention on the possible mechanisms of their action. Although not without exception, results from animal and human studies suggest a moderate cholesterol-lowering action of dairy products fermented with appropriate strain(s) of lactic acid bacteria and bifidobacteria. Mechanistically, probiotic bacteria ferment food-derived indigestible carbohydrates to produce short-chain fatty acids in the gut, which can then cause a decrease in the systemic levels of blood lipids by inhibiting hepatic cholesterol synthesis and/or redistributing cholesterol from plasma to the liver. Furthermore, some bacteria may interfere with cholesterol absorption from the gut by deconjugating bile salts and therefore affecting the metabolism of cholesterol, or by directly assimilating cholesterol. For prebiotic substances, the majority of studies have been done with the fructooligosaccharides inulin and oligofructose, and although convincing lipid-lowering effects have been observed in animals, high dose levels had to be used. Reports in humans are few in number. In studies conducted in normal-lipidemic subjects, two reported no effect of inulin or oligofructose on serum lipids, whereas two others reported a significant reduction in serum triglycerides (19 and 27%, respectively) with more modest changes in serum total and LDL cholesterol. At present, data suggest that in hyperlipidemic subjects, any effects that do occur result primarily in reductions in cholesterol, whereas in normal lipidemic subjects, effects on serum triglycerides are the dominant feature.
Resumo:
It is evident that quantitative information on different microbial groups and their contribution in terms of activity in the gastrointestinal (GI) tract of humans and animals is required in order to formulate functional diets targeting improved gut function and host health. In this work, quantitative information on levels and spatial distributions of Bacteroides spp, Eubacterium spp, Clostridium spp, Escherichia coli, Bifidobacterium spp and Lactobacillus/Enterococcus spp. along the porcine large intestine was investigated using 16S rRNA targeted probes and fluorescent in situ hybridisation (FISH). Caecum, ascending colon (AC) and rectum luminal digesta from three groups of individually housed growing pigs fed either a corn-soybean basal diet (CON diet) or a prebiotic diet containing 10 g/kg oligofructose (FOS diet) or trans-galactooligosaccharides (TOS diet) at the expense of cornstarch were analysed. DAPI staining was used to enumerate total number of cells in the samples. Populations of total cells, Bacteroides, Eubacterium, Clostridium and Bifidobacterium, declined significantly (P < 0.05) from caecum to rectum, and were not affected by dietary treatments. Populations of Lactobacillus/ Enterococcus and E coli did not differ throughout the large intestine. The relative percent (%) contribution of each bacterial group to the total cell count did not differ between caecum and rectum, with the exception of Eubacterium that was higher in the AC digesta. FISH analysis showed that the sum of all bacterial groups made up a small percentage of the total cells, which was 12.4%, 21.8% and 10.3% in caecum, AC and rectum, respectively. This supports the view that in swine, the diversity of GI microflora might be higher compared to other species. In terms of microflora metabolic activity, the substantially higher numerical trends seen in FOS and TOS treatments regarding total volatile fatty acid, acetate concentrations and glycolytic activities, it could be postulated that FOS and TOS promoted saccharolytic activities in the porcine colon. (c) 2006 Elsevier Ltd. All rights reserved.
Resumo:
Insulin is a prebiotic food ingredient, which suppresses colon tumour growth and development in rats. In the gut lumen, it is fermented to lactic acid and short chain fatty acids (SCFA). Of these, butyrate has suppressing agent activities, but little is known concerning cellular responses to complex fermentation samples. To investigate the effects of fermentation products of insulin on cellular responses related to colon carcinogenesis. Fermentations were performed in anaerobic batch cultures or in a three-stage fermentation model that simulates conditions in colon-segments (proximal, transverse, distal). Substrate was insulin enriched with oligofructose (Raftilose® Synergy1), fermented with probiotics (Bifidobacterium lactis Bb12, Lactobacillus rhamnosus GG), and/or faecal inocula. HT29 or CaCo-2 cells were incubated with supernatants of the fermented samples (2.5%-25% v/v, 24-72 hours). Cellular parameters of survival, differentiation, tumour progression, and invasive growth were determined. Fermentation supernatants derived from probiotics and Synergy1 were more effective than with glucose. The additional fermentation with faecal slurries produced supernatants with lower toxicity, higher SCFA contents, and distinct cellular functions. The supernatant derived from the gut model vessel representing the distal colon, was most effective for all parameters, probably on account of higher butyrate-concentrations. Biological effects of insulin upon colon cells may be mediated not only by growth stimulation of the lactic acid-producing bacteria and/or production of butyrate, but also by other bacteria and products of the gut lumen. These newly reported properties of the supernatants to inhibit growth and metastases in colon tumour cells are important mechanisms of tumour suppression.