Uso de maltodextrina e prebiótico em rações de leitões desmamados

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fiber, a component for health gastrointestinal endocrine system

Dietary fiber was classified according to its solubility in an attempt to relate physiological effects to chemical types of fiber. Soluble fibers (B-glucans, gums, wheat dextrin, psyllium, pectin, inulin) were considered to have benefits on serum lipids, while insoluble fibers (cellulose, lignin, pectins, hemicelluloses) were linked with laxation benefits. More important characteristics of fiber in terms of physiological benefits are viscosity and fermentability. Viscous fibers (pectins, B-glucans, gums, psyllium) are those that have gel-forming properties in the intestinal tract, and fermentable fibers (wheat dextrin, pectins, B-glucans, gum, inulin) are those that can be metabolized by colonic bacteria. Objective: To summarize the beneficial effects of dietary fiber, as nutraceuticals, in order to maintain a healthy gastrointestinal system. Methods: Our study is a systematic review. Electronic databases, including PubMed, Medline, with supplement of relevant websites, were searched. We included randomized and non-randomized clinical trials, epidemiological studies (cohort and case-control). We excluded case series, case reports, in vitro and animal studies. Results: The WHO, the U.S. Food and Drug Administration (FDA), the Heart Foundation and the Romanian Dietary Guidelines recommends that adults should aim to consume approximately 25–30 g fiber daily. Dietary fiber is found in the indigestible parts of cereals, fruits and vegetables. There are countries where people don’t eat enough food fibers, these people need to take some kind of fiber supplement. Evidence has been found that dietary fiber from whole foods or supplements may (1) reduce the risk of cardiovascular disease by improving serum lipids and reducing serum total and low-density lipoprotein (LDL) cholesterol concentrations, (2) decreases the glycaemic index of foods, which leads to an improvement in glycemic response, positive impact on diabetes, (3) protect against development of obesity by increasing satiety hormone leptin concentrations, (4) reduced risk of developing colorectal cancer by normalizes bowel movements, improve the integrity of the epithelial layer of the intestines, increase the resistance against pathogenic colonization, have favorable effects on the gut microbiome, wich is the second genomes of the microorganisms, (5) have a positive impact on the endocrine system by gastrointestinal polypeptide hormonal regulation of digestion, (6) have prebiotic effect by short-chain fatty acids (SCFA) production; butyrate acid is the preferred energy source for colonic epithelial cells, promotes normal cell differentiation and proliferation, and also help regulate sodium and water absorption, and can enhance absorption of calcium and other minerals. Although all prebiotics are fiber, not all fiber is prebiotic. This generally refers to the ability of a fiber to increase the growth of bifidobacteria and lactobacilli, which are beneficial to human health, and (7) play a role in improving immune function via production of SCFAs by increases T helper cells, macrophages, neutrophils, and increased cytotoxic activity of natural killer cells. Conclusion: Fiber consumption is associated with high nutritional value and antioxidant status of the diet, enhancing the effects on human health. Fibers with prebiotic properties can also be recommended as part of fiber intake. Due to the variability of fiber’s effects in the body, it is important to consume fiber from a variety of sources. Increasing fiber consumption for health promotion and disease prevention is a critical public health goal.

Effect of dietary inulin as prebiotic on growth, survival and intestinal bacterial density of juvenile great sturgeon (Huso huso)

Use of prebiotics, nondigestible dietary ingredients that beneficially affect the host by selectively stimulating the growth of and/or activating the metabolism of healthpromoting bacteria in the intestinal tract, is a novel concept in aquaculture. An 8-week feeding experiment was conducted to investigate the effects of dietary prebiotic inulin on the growth performance, intestinal bacterial density, body composition and values of blood serum enzymes in the juvenile great sturgeon (Huso huso). Three replicate groups of fish (initially averaging weight 16.14±0.38g) were fed diets containing prebiotic inulin at levels ranging from 1% to 3%. The basal diet was contained 3% cellulose. The results of linear regression showed there was a negative relationship between some performance indices including weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER), net protein utilization (NPU), energy retention (ERE), feed efficincy (FE), protein retention (PR) and supplementation level of inulin. At the end of trial, the 1% inulin treatment insignificantly showed an enhaced survival between the treatment groups. Intestinal lactic acid bacteria (LAB) increased in group treated with 1% inulin compare to other groups. No significant difference were observed in body composition and level of serum enzymes (P>0.05). Moreover there was significant correlation between ALT and LDH values (P<0.01). Result obtained in this study shows that the prebiotic inulin didn’t influence the increase of the growth performance of juvenile great sturgeon and it is not appropriate for supplementation in the diet of beluga.

Effect of pH and dose on the growth of gut bacteria on prebiotic carbohydrates in vitro

The effect of pH and substrate dose on the fermentation profile of a number of commercial prebiotics was analysed in triplicate using stirred, pH and temperature controlled anaerobic batch culture fermentations, inoculated with a fresh faecal slurry from one of three healthy volunteers. Bacterial numbers were enumerated using fluorescence in situ hybridisation. The commercial prebiotics investigated were fructooligosaccharides (FOS), inulin, galactooligosaccharides (GOS), isomaltooligosaccharides (IMO) and lactulose. Two pH values were investigated, i.e. pH 6 and 6.8. Doses of 1% and 2% (w/v) were investigated, equivalent to approximately 4 and 8 g per day, respectively, in an adult diet. It was found that both pH and dose altered the bacterial composition. It was observed that FOS and inulin demonstrated the greatest bifidogenic effect at pH 6.8 and 1% (w/v) carbohydrate, whereas GOS, IMO and lactulose demonstrated their greatest bifidogenic effect at pH 6 and 2% (w/v) carbohydrate. From this we can conclude that various prebiotics demonstrate differing bifidogenic effects at different conditions in vitro. (C) 2003 Elsevier Science Ltd. All rights reserved.

In vitro fermentation characteristics of whole grain wheat flakes and the effect of toasting on prebiotic potential

Population studies have shown a positive correlation between diets rich in whole grains and a reduced risk of developing metabolic diseases, like diabetes, cardiovascular disease, and certain cancers. However, little is known about the mechanisms of action, particularly the impact different fermentable components of whole grains have on the human intestinal microbiota. The modulation of microbial populations by whole grain wheat flakes and the effects of toasting on digestion and subsequent fermentation profile were evaluated. Raw, partially toasted, and toasted wheat flakes were digested using simulated gastric and small intestinal conditions and then fermented using 24-hour, pH-controlled, anaerobic batch cultures inoculated with human feces. Major bacterial groups and production of short-chain fatty acids were compared with those for the prebiotic oligofructose and weakly fermented cellulose. Within treatments, a significant increase (P<.05) in bifidobacteria numbers was observed upon fermentation of all test carbohydrates, with the exception of cellulose. Toasting appeared to have an effect on growth of lactobacilli as only fermentation of raw wheat flakes resulted in a significant increase in levels of this group.

Effect of probiotic and prebiotic inclusion in weaned piglet diets on structure and ultra-structure of small intestine

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Evaluation of microbial adjuncts and their effect on the ripening of cheddar cheese

A bacteriocin-producing strain of Lactobacillus paracasei DPC 4715 was used as an adjunct culture in Cheddar cheese in order to control the growth of “wild” nonstarter lactic acid bacteria. No suppression of growth of the indicator strain was observed in the experimental cheese. The bacteriocin produced by Lactobacillus paracasei DPC 4715 was sensitive to chymosin and cathepsin D and it may have been cleaved by the rennet used for the cheese manufactured or by indigenous milk proteases. A series of studies were performed using various microbial adjuncts to influence cheese ripening. Microbacterium casei DPC 5281, Corynebacterium casei DPC 5293 and Corynebacterium variabile DPC 5305 were added to the cheesemilk at level of 109 cfu/ml resulting in a final concentration of 108 cfu/g in Cheddar cheese. The strains significantly increased the level of pH 4.6-soluble nitrogen, total free amino acids after 60 and 180 d of ripening and some individual free amino acids after 180 d. Yarrowia lipolytica DPC 6266, Yarrowia lipolytica DPC 6268 and Candida intermedia DPC 6271 were used to accelerate the ripening of Cheddar cheese. Strains were grown in YG broth to a final concentration of 107 cfu/ml, microfluidized, freeze-dried and added to the curd during salting at level of 2% w/w. The yeasts positively affected the primary, secondary proteolysis and lipolysis of cheeses and had aminopeptidase, dipeptidase, esterase and 5’ phosphodiestere activities that contributed to accelerate the ripening and improve the flavor of cheese. Hafia alvei was added to Cheddar cheesemilk at levels of 107 cfu/ml and 108 cfu/ml and its contribution during ripening was evaluated. The strain significantly increased the level of pH 4.6-soluble nitrogen, total free amino-acids, and some individual free amino-acids of Cheddar cheese, whereas no differences in the urea-polyacrylamide gel electrophoresis (urea-PAGE) electrophoretograms of the cheeses were detected. Hafia alvei also significantly increased the level of some biogenic amines. A low-fat Cheddar cheese was made with Bifidobacterium animalis subsp. lactis, strain BB-12® at level of 108 cfu/ml, as a probiotic adjunct culture and Hi-Maize® 260 (resistant high amylose maize starch) at level of 2% and 4% w/v, as a prebiotic fiber which also played the role of fat replacer. Bifidobacterium BB-12 decreased by 1 log cycle after 60 d of ripening and remained steady at level of ~107 cfu/g during ripening. The Young’s modulus also increased proportionally with increasing levels of Hi-maize. Hencky strain at fracture decreased over ripening and increased with increasing in fat replacer. A cheese based medium (CBM) was developed with the purpose of mimicking the cheese environment at an early ripening stage. The strains grown in CBM showed aminopeptidase activity against Gly-, Arg-, Pro- and Phe-p-nitroanalide, whereas, when grown in MRS they were active against all the substrates tested. Both Lb. danicus strains grown in MRS and in CBM had aminotransferase activity towards aromatic amino acids (Phe and Trp) and also branched-chain amino acids (Leu and Val). Esterase activity was expressed against p-nitrophenyl-acetate (C2), pnitrophenyl- butyrate (C4) and p-nitrophenyl-palmitate (C16) and was significantly higher in CBM than in MRS.

Metabolism of the soyabean isoflavone glycoside genistin in vitro by human gut bacteria and the effect of prebiotics

The isoflavone genistein is found predominantly in soyabeans and is thought to possess various potent biological properties, including anticarcinogenic effects. Studies have shown that genistein is extensively degraded by the human gut microflora, presumably with a loss of its anti-carcinogenic action. The aim of the present study was to investigate the potential of a prebiotic to divert bacterial metabolism away from genistein breakdown: this may be of benefit to the host. Faecal samples were obtained from healthy volunteers and fermented in the presence of a source of soyabean isoflavones (Novasoy(TM) (10 g/l); ADM Neutraceuticals, Erith, Kent, UK). Bacterial genera of the human gut were enumerated using selective agars and genistein was quantified by HPLC. The experiment was repeated with the addition of glucose (10 g/l) or fructo-oligosaccharide (10 g/l; FOS) to the fermentation medium. The results showed most notably that counts of Bifidobacterium spp. and Lactobacillus spp. were significantly increased (P<0.05 and P<0.01 respectively) under steady-state conditions in the presence of FOS. Counts of Bacteroides spp. and Clostridium spp. were, however, both significantly reduced (P<0.05) during the fermentation. A decline in genistein concentration by about 52 and 56% over the 120h culture period was observed with the addition of glucose or FOS to the basal medium (P<0.01), compared with about 91% loss of genistein in the vessels containing Novasoy(TM) (ADM Neutraceuticals) only. Similar trends were obtained using a three-stage chemostat (gut model), in which once again the degradation of genistein was about 22% in vessel one, about 24% in vessel two and about 26% in vessel three in the presence of FOS, compared with a degradation of genistein of about 67% in vessel one, about 95% in vessel two and about 93% in vessel three in the gut model containing Novasoy(TM) (ADM Neutraceuticals) only. The present study has shown that the addition of excess substrate appeared to preserve genistein in vitro. In particular, the use of FOS not only augmented this effect, but also conferred an additional benefit in selectively increasing numbers of purportedly beneficial bacteria such as bifidobacteria and lactobacilli.

Clinical trial: the effects of a trans-galactooligosaccharide prebiotic on faecal microbiota and symptoms in irritable bowel syndrome

Gut microflora-mucosal interactions may be involved in the pathogenesis of irritable bowel syndrome (IBS). To investigate the efficacy of a novel prebiotic trans-galactooligosaccharide in changing the colonic microflora and improve the symptoms in IBS sufferers. In all, 44 patients with Rome II positive IBS completed a 12-week single centre parallel crossover controlled clinical trial. Patients were randomized to receive either 3.5 g/d prebiotic, 7 g/d prebiotic or 7 g/d placebo. IBS symptoms were monitored weekly and scored according to a 7-point Likert scale. Changes in faecal microflora, stool frequency and form (Bristol stool scale) subjective global assessment (SGA), anxiety and depression and QOL scores were also monitored. The prebiotic significantly enhanced faecal bifidobacteria (3.5 g/d P < 0.005; 7 g/d P < 0.001). Placebo was without effect on the clinical parameters monitored, while the prebiotic at 3.5 g/d significantly changed stool consistency (P < 0.05), improved flatulence (P < 0.05) bloating (P < 0.05), composite score of symptoms (P < 0.05) and SGA (P < 0.05). The prebiotic at 7 g/d significantly improved SGA (P < 0.05) and anxiety scores (P < 0.05). The galactooligosaccharide acted as a prebiotic in specifically stimulating gut bifidobacteria in IBS patients and is effective in alleviating symptoms. These findings suggest that the prebiotic has potential as a therapeutic agent in IBS.

In vitro investigation into the potential prebiotic activity of honey oligosaccharides

The effect of honey oligosaccharides on the growth of fecal bacteria was studied using an in vitro fermentation system. Prior to treatment, glucose and fructose (31.73 and 21.41 g/100 g of product, respectively) present in honey, which would be digested in the upper gut, were removed to avoid any influence on bacterial populations in the fermentations. Nanofiltration, yeast (Saccharomyces cerevisiae) treatment, and adsorption onto activated charcoal were used to remove monosaccharides. Prebiotic (microbial fermentation) activities of the three honey oligosaccharide fractions and the honey sample were studied and compared with fructooligosaccharide (FOS), using 1% (w/v) fecal bacteria in an in vitro fermentation system (10 mg of carbohydrate, 1.0 mL of basal medium). A prebiotic index (PI) was calculated for each carbohydrate source. Honey oligosaccharides seem to present potential prebiotic activity (PI values between 3.38 and 4.24), increasing the populations of bifidobacteria and lactobacilli, although not to the levels of FOS (PI of 6.89).

Weight of evidence needed to substantiate a health effect for probiotics and prebiotics: regulatory considerations in Canada, EU, and US

Successful and responsible introduction of probiotic and prebiotic products into the worldwide marketplace requires labelling for health benefits that meets consumer needs, adheres to regulatory standards and does not overextend scientific evidence. Regulations differ among countries, but underlying all is an emphasis on scientific credibility of any statements of health benefits. This paper considers the value of different types of evidence offered in substantiation of efficacy and reviews different regulatory approaches to labelling for health claims. Limitations of in vitro, animal and different types of human studies used for efficacy substantiation for probiotics and prebiotics are discussed.

Potential prebiotic activity of oligosaccharides obtained by enzymatic conversion of durum wheat insoluble dietary fibre into soluble dietary fibre

Background and aims: Epidemiological evidence indicates that cereal dietary fibre (DF) may have several cardiovascular health benefits. The underlying mechanisms have not yet been elucidated. Here, the potential nutritional effects of physico-chemical. properties modifications of durum wheat dietary fibre (DWF) induced by enzyme treatment have been investigated. Methods and results: The conversion of the highly polymerised insoluble dietary fibre into soluble feruloyl oligosaccharides of DWF was achieved by a tailored enzymatic treatment. The in vitro fermentation and release of ferulic acid by intestinal microbiota from DWF before and after the enzymatic treatment were assessed using a gut model validated to mimic the human colonic microbial environment. Results demonstrated that, compared to DWF, the enzyme-treated DWF (ETD-WF) stimulated the growth of bifidobacteria and lactobacilli. Concurrently, the release of free ferulic acid by ET-DWF was almost three times higher respect to the control. No effect on the formation of short chain fatty acids was observed. Conclusions: The conversion of insoluble dietary fibre from cereals into soluble dietary fibre generated a gut microbial fermentation that supported bifidobacteria and lactobacilli. The concurrent increase in free ferulic acid from the enzyme-treated DWF might result in a higher plasma ferulic acid concentration which could be one of the reasons for the health benefits reported for dietary fibre in cardiovascular diseases. (c) 2008 Elsevier B.V. All rights reserved.

Fibre and effects on probiotics (the prebiotic concept)

The burden (economic and medicinal) of acute and chronic gut disorders continues to increase. As efficient therapies are few, attention has turned towards the use of so-called functional foods to mediate against gut disorder. These target particular genera of gut bacteria seen as beneficial, e.g. bifidobacteria, lactobacilli. The use of products containing live microbial species (probiotics) has a long history of use in humans and many trials have been reported as 'positive'. Taking the view that positive components of the gut flora already exist in the intestinal tract, the prebiotic concept has been developed. Here, dietary carbohydrates have a selective metabolism within the gut flora thereby shifting the community towards a more advantageous structure. Conventional fibres like pectins, cellulose, etc. are not selectively metabolised by gut bacteria. However, certain oligosaccharides do have this capability. Most research has been conducted with fructooligosaccharides, like inulin, which have a powerful bifidogenic effect. Trials are ongoing to determine the clinical benefits of prebiotic use. Intestinal disorders like ulcerative colitis, gastroenteritis and irritable bowel syndrome are particular targets. (c) 2004 Elsevier Ltd. All rights reserved.

Prebiotic evaluation of a novel galactooligosaccharide mixture produced by the enzymatic activity of Bifidobacterium bifidum NCIMB 41171, in healthy humans: a randomized, double-blind, crossover, placebo-controlled intervention study

Background: Galactooligosaccharides are selectively fermented by the beneficial member of the colonic microflora contributing to the health of the host. Objective: We assessed the prebiotic potential of a novel galactooligosaccharide produced through the action of beta-galactosidases, originating from a probiotic Bifidobacterium bifidum strain, against a galactooligosaccharide produced through the action of an industrial P-galactosidase and a placebo. Design: Fifty-nine healthy human volunteers participated in this study. Initially, the effect of the matrix on the prebiotic properties of a commercially available galactooligosaccharide (7 g/d) was assessed during 7-d treatment periods with a 7-d washout period in between. During the second phase, 30 volunteers were assigned to a sequence of treatments (7 d) differing in the amount of the novel galactooligosaccharide (0, 3.6, or 7 g/d). Stools were recovered before and after each intervention, and bacteria numbers were determined by fluorescent in situ hybridization. Results: Addition of the novel galactooligosaccharide mixture significantly increased the bifidobacterial population ratio compared with the placebo (P < 0.05), whereas 7 g/d of the novel galactooligosaccharide significantly increased the bifidobacterial ratio compared with the commercial galactooligosaccharide (P < 0.05). Moreover, a significant relation (P < 0.001) between the bifidobacteria proportion and the novel galactooligosaccharide dose (0, 3.6, and 7 g/d) was observed. This relation was similar to the effect of the novel galactooligosaccharide on the prebiotic index of each dose. Conclusions: This study showed that galactooligosaccharide mixtures produced with different beta-galactosidases show different prebiotic properties and that, by using enzymes originating from bifidobacterial species, an increase in the bifidogenic properties of the prebiotic product is achievable.

Effect of molecule branching and glycosidic linkage on the degradation of polydextrose by gut microbiota.

Polydextrose is a randomly linked complex glucose oligomer that is widely used as a sugar replacer, bulking agent, dietary fiber and prebiotic. Polydextrose is poorly utilized by the host and, during gastrointestinal transit, it is slowly degraded by intestinal microbes, although it is not known which parts of the complex molecule are preferred by the microbes. The microbial degradation of polydextrose was assessed by using a simulated model of colonic fermentation. The degradation products and their glycosidic linkages were measured by combined gas chromatography and mass spectrometry, and compared to those of intact polydextrose. Fermentation resulted in an increase in the relative abundance of non-branched molecules with a concomitant decrease in single-branched glucose molecules and a reduced total number of branching points. A detailed analysis showed a preponderance of 1,6 pyranose linkages. The results of this study demonstrate how intestinal microbes selectively degrade polydextrose, and provide an insight into the preferences of gut microbiota in the presence of different glycosidic linkages.