Inulin and oligofructose as dietary fiber: a review of the evidence

This critical review article examines the composition and source of inulin and oligofructose, the physiological effects of their consumption, and how these materials relate to the concept of dietary fiber. Inulin and oligofructose are fructans extracted on a commercial basis from the chicory root. Inulin has been defined as a polydisperse carbohydrate material consisting mainly, if not exclusively, of beta (2-1) fructosyl-fructose links ranging from 2 to 60 units long. Native chicory inulin has an average degree of polymerization (DP) of 10 to 20, whereas oligofructose contains chains of DP 2 to 10, with an average DP of 4. While a universally accepted definition for dietary fiber does not exist, it is generally agreed that this term includes saccharides (+ lignin) that are not hydrolyzed or absorbed in the upper part of the gastrointestinal tract. These materials reach the colon, where they may be totally fermented, partially fermented, or remain unfermented. In addition, fibers contribute to fecal bulking. Inulin and oligofructose are not digested in the upper part of the gastrointestinal tract or are they absorbed and metabolized in the glycolytic pathway, or directly stored as glycogen like 'sugars' or starches. None of the molecules of fructose and glucose that form inulin and oligofructose appear in the portal blood. These materials are quantitatively fermented by the microflora of the colon; further, it has been demonstrated that this fermentation leads to the selective stimulation of the growth of the bifidobacteria population. After reviewing their chemistry, origin, and physiological effects, it is the opinion of the authors that inulin and oligofructose are dietary fiber. They share the basic common characteristics of dietary fibers, that is, saccharides of plant origin, resistance to digestion and absorption in the small intestine, and fermentation in the colon to produce short-chain fatty acids that are absorbed and metabolized in various parts of the body. Moreover, this fermentation induces a bulking effect.     

Chicory inulin does not increase stool weight or speed up intestinal transit time in healthy male subjects

Inulin is a non-digestible oligosaccharide classified as a prebiotic, a substrate that promotes the growth of certain beneficial microorganisms in the gut. We examined the effect of a 20 g day(-1) supplement of chicory inulin on stool weight, intestinal transit time, stool frequency and consistency, selected intestinal microorganisms and enzymes, fecal pH, short chain fatty acids and ammonia produced as by-products of bacterial fermentation. Twelve healthy male volunteers consumed a well-defined, controlled diet with and without a 20 g day(-1) supplement of chicory inulin (degree of polymerization (DP) ranging for 2-60), with each treatment lasting for 3 weeks in a randomized, double-blind crossover trial. Inulin was consumed in a low fat ice cream. No differences were found in flavor or appeal between the control and inulin-containing ice creams. Inulin consumption resulted in a significant increase in total anaerobes and Lactobacillus species and a significant decrease in ammonia levels and β-glucuronidase activity. Flatulence increased significantly with the inulin treatment. No other significant differences were found in bowel function with the addition of inulin to the diet. Thus, inulin is easily incorporated into a food product and has no negative effects on food acceptability. Twenty grams of inulin was well tolerated, but had minimal effects on measures of laxation in healthy, human subjects.     

菊粉和低聚果糖在早餐谷物中的应用

<正> 早餐对人体是非常重要的,然而,并非每个人都有进食早餐的习惯,尤其是生活于繁忙之中的都市人。美国著名的谷物类早餐生产商Kellogg's公司指出,欧洲有700万小孩是不吃早餐的。 事实上,早餐除了是碳水化合物、纤维素和维生素的重要来源外,它与人体健康也密切相关,尤其是“高纤维素”谷物、维生素和矿物质强化早餐。 早餐谷物、酸奶和乳饮料,是理想的功能性食品组合。在早餐谷物中添加低聚果糖或菊粉,则能更进一步强化     

菊粉的特性及在特殊医学用途配方食品中的应用前景

菊粉及其次级酶解产物低聚果糖作为一种天然的膳食纤维,不仅可提供膳食纤维的功效,更可促进有益菌的生长,在预防便秘和腹泻,以及抑制有害发酵产物,预防结肠癌方面起到积极的作用。同时,菊粉还具有提高矿质元素的生物利用率、降血糖、降血脂及控制体质量等特性,在预防和控制肠道疾病、肥胖病、糖尿病和心血管病等慢性疾病方面有很好的作用。该文综述了菊粉理化性质、生理功能、安全性评价及在特殊医学用途配方食品中的应用前景。     

Nutritional responses to the presence of inulin and oligofructose in the diets of domesticated animals: a review

Inulin and oligofructose are prebiotic oligosaccharides fermented in the large intestine. This article provides an extensive review of the effects of these oligosaccharides on gastrointestinal characteristics (microflora, pathogen control, epithelial cell proliferation, putrefactive compound production, fecal characteristics, and nutrient digestibility) and systemic metabolism of carbohydrates, nitrogen, lipids, and minerals in dogs, cats, horses, calves, pigs, poultry, and rabbits. In addition, intake of inulin and oligofructose and considerations in their supplementation to animal diets are discussed. Growth performance and meat production in livestock in response to inulin and oligofructose supplementation are addressed. Finally, the possible substitution of antibiotics with fructans in animal diets and directions for future research are presented.     

Dietary fiber,inulin, and oligofructose: A review comparing their physiological effects

Dietary fiber is a general terra. It covers a wide variety of substances that belong to the family of carbohydrates that resist hydrolysis by human alimentary enzymes but are fermented by colonie microflora.

The main physiological effects of dietary fiber are primarily on gastric emptying and small intestinal transit time, resulting in an improved glucose tolerance and a decreased digestion of starch; second, on colonie transit time and large bowel functions due to fermentation by ceco‐colonic microbial flora or bulking action.

The so‐called soluble dietary fibers are fermented to a large extent by a wide variety of anaerobic bacteria that result in an increase in bacterial biomass, an increase in fecal mass, a change in intracolonic pH, and production of short chain fatty acids and various gases as metabolic end products. The insoluble fibers are only marginally fermented; they serve almost exclusively as bulking agents that result in shorter transit time and increased fecal mass.

The short chain fatty acids resulting from the colonie fermentation of dietary fiber are largely absorbed via the portal blood and reach both the liver and the peripheral tissues. They induce changes in glucose and fat metabolism leading to post‐prandial hypoglycemia and long‐term hypolipidemia.

Inulin and oligofructose are fructans with a degree of polymerization of 2 to 60 and 2 to 20. respectively. Due to the structural conformation of their osidic bridge ((3 2–1), they both resist the hydrolysis by human alimentary enzymes. Moreover, when reaching the colon, both inulin and oligofructose are almost quantitatively fermented almost exclusively by colonie bifidobacteria and bacteroides. Such an extensive fermentation causes an increase in fecal bacterial biomass, a decrease in ceco‐colonic pH. and produces a large amount of fermentation products among which the short chain fatty acids that exert systemic effects on lipid metabolism.

Thus, both inulin and oligofructose have most of the characteristics of a dietary fiber and the proposal is made to classify them as such. Moreover, they are bifidogenic factors, because, due to still unknown reasons, they are primarily fermented by bifidobacteria.

It is concluded from this review that “nondigestible fructooligosaccharides.” even though they arc not included in the carbohydrate fraction that is quantified as dietary fiber by classic analytical methods, have most of the physiological effects of a dietary fiber. Because it has become necessary for the consumer to be informed clearly and specifically on the nature and the beneficial effects of all fermentable carbohydrates that will “feed” their colon, it is suggested that food labeling should be extended to include such products in the dietary liber fraction.     

Effects of dietary fiber on inflammatory bowel disease

The chronic idiopathic inflammatory bowel diseases (IBDs), namely Crohn's disease and ulcerative colitis, appear to be derived from an inappropriate reaction towards a luminal agent, most probably driven by the intestinal microflora, which upregulates the synthesis and release of different pro-inflammatory mediators, thus contributing to tissue damage that characterizes these intestinal conditions. Several studies have reported that IBD is associated with impairment in short-chain fatty acid (SCFA) production, mainly acetate, propionate, and butyrate. They are produced in the large bowel by anaerobic bacterial fermentation of undigested dietary carbohydrates and fiber polysaccharides, with butyrate being considered as the major fuel source for colonocytes. These SCFAs have been proposed to play a key role in the maintenance of colonic homeostasis. Therefore, it is reasonable to consider therapeutic approaches that increase colonic SCFA production, as it can be achieved by administration of dietary fiber to IBD patients. Unfortunately, there is quite limited documentation of efficacy of dietary fiber in properly designed trials. This review discusses the rationale, available evidence for the use of dietary fiber and its mechanisms of action in the treatment and prevention of IBDs.     

肠道菌群利用膳食纤维及其与人体健康关系研究进展

膳食纤维具有提供能量、增强机体免疫的功能,对于人体健康至关重要,被营养学界认定为与蛋白质、脂肪、碳水化合物、维生素、矿物质与水并列的第7类营养素。肠道菌群能激活和维持人的免疫系统和新陈代谢的稳定性,肠道菌群的稳态对人体的发育和成熟至关重要。肠道菌群能够消化膳食纤维,二者之间存在着复杂的相互作用,共同促进和维持肠道健康。近年来,膳食纤维与肠道菌群之间的相互作用受到了科学家广泛关注并取得很大进展。该文就膳食纤维、肠道菌群及其与人体健康关系的研究现状进行了回顾和展望,为深入了解膳食纤维对人体的作用,合理调整膳食结构,促进肠道健康提供参考。     

菊粉和大豆膳食纤维对牛肉饮食的小鼠肠道菌群及其代谢产物的改善作用

红肉的大量摄入会导致其未消化成分经肠道菌群发酵形成有害代谢产物,从而破坏肠稳态,增加患结肠癌、心血管疾病的风险.为探究添加菊粉和大豆膳食纤维对牛肉饮食小鼠的肠道菌群及代谢产物的影响,本实验将雄性C57BL/6Cnc小鼠随机分为空白对照组、牛肉组、牛肉与菊粉组和牛肉与大豆膳食纤维组,通过16S rRNA高通量测序技术检测...     

菊糖的提取、性质和应用

概述了菊芋中菊糖的性质、提取、功能作用以及在食品中的应用。     

Prebiotic effects of fermentable carbohydrate polymers may be modulated by faecal bulking of non‐fermentable polysaccharides in the large bowel of rats

This study investigated the impact of supplementary fermentable polysaccharides inulin (a prebiotic) and barley β‐glucan on the large bowel, when consumed against a background high or low intake of mixed non‐starch polysaccharide. Rats were fed for 28 days with diets containing high (15%) and low (5%) background dietary fibre (BDF; cellulose plus sugar beet fibre), with or without 5% supplementary fermentable fibre (SFF; inulin or barley β‐glucan). High‐BDF diets unsupplemented with inulin or barley β‐glucan caused greater improvement than supplemented low‐BDF diets in several parameters linked to gut health: they increased colonic Bifidobacterium spp., butyric acid concentration in the caecum, and colonic crypt depth more than inulin and barley β‐glucan. For these parameters, inulin and barley β‐glucan added little to the effects of the high‐BDF diet alone. Furthermore, by allowing for dilution due to the greater faecal bulk induced by the mixed fibre compared with inulin or barley β‐glucan, the total quantity of butyric acid in the colon of BDF‐fed rats was greatly amplified. Interpretation of the effects of prebiotics in diets containing dietary fibre requires concurrent analysis of the multiple effects of non‐fermentable bulk.     

Effect of dietary mineral level and inulin inclusion on phosphorus,calcium and nitrogen utilisation,intestinal microflora and bone development

BACKGROUND: An experiment was conducted to investigate the interaction between dietary phosphorus (P) level (4 vs 6 g total P kg^?1) and inulin inclusion (0 vs 20 g kg^?1) on coefficients of total tract apparent digestibility, nitrogen (N), P and calcium (Ca) utilisation, bone mineralisation, selected gastrointestinal microflora, intestinal volatile fatty acid concentrations and digesta pH in the ileum, caecum and proximal colon. Owing to the design of the experiment, as dietary P level increased, there was also an increase in dietary Ca level in order to maintain a sustainable dietary Ca/P ratio. Entire male finisher pigs (n = 10 per treatment) with a similar initial body weight (51 kg, standard deviation 2.4 kg) were used. RESULTS: Inulin inclusion lowered (P < 0.01) Enterobacteriaceae populations in the proximal colon compared with pigs offered diets without added inulin. However, intestinal bacterial populations of Lactobacillus and Bifidobacterium spp. were unaffected. Inulin inclusion had no effect on mineral digestibility or bone mineralisation. Pigs offered low P and Ca diets had lower (P < 0.01) bone mineralisation than pigs offered high P and Ca diets. CONCLUSION: Intestinal bacterial populations of Enterobacteriaceae in the proximal colon were lowered by inulin inclusion. Inulin inclusion did not affect P, Ca or N utilisation or bone mineralisation in the finisher pig when offered either a low or a high P diet. Increasing the P and Ca content of the diet led to an increase in bone mineralisation. Copyright © 2010 Society of Chemical Industry     

菊粉生物学作用及机制研究进展

菊粉是一种水溶的膳食纤维,近年来,菊粉作为保健食品或食品添加剂得到广泛应用。该文对菊粉多种有益的生物学功能、特定条件下可能存在的风险以及菊粉发挥生物学功能的作用机制进行总结,以期为菊粉作为保健食品、食品添加剂和医用辅料的安全性和有效性提供依据。     

Effects of low rumen-degradable protein or abomasal fructan infusion on diet digestibility and urinary nitrogen excretion in lactating dairy cows

Post-ileal carbohydrate fermentation in dairy cows converts blood urea nitrogen (BUN) into fecal microbial protein. This should reduce urinary N, increase fecal N, and reduce manure NH₃ volatilization. However, if intestinal BUN recycling competes with ruminal BUN recycling, hindgut fermentation may reduce NH₃ for rumen microbial protein synthesis. Eight lactating Holstein cows were used in a replicated 4 × 4 Latin square design with 14-d periods. Treatments were arranged as a 2 × 2 factorial. Diets contained either adequate rumen-degradable protein (RDP; high RDP) or were 28% below predicted RDP requirements (low RDP). Cows received abomasal infusions of either 10 L/d of saline or 10 L/d of saline containing 1 kg/d of inulin. We hypothesized that reducing ruminal NH₃, either by restricting RDP intake or by diverting BUN to feces with inulin, would reduce rumen microbial protein synthesis, as would be evidenced by significant main effects of treatments on rumen NH₃, milk production, and urinary purine derivative excretion. Furthermore, we thought it likely that effects of inulin might be greater when rumen NH₃ was already low, as would be indicated by significant interactions between inulin infusion and dietary RDP level on rumen NH₃, milk production, and urinary purine derivative excretion. Rumen NH₃ was reduced by the low-RDP diet, but urinary purine derivative excretion and milk production were unaffected. However, the low-RDP diet reduced apparent total tract digestibility of OM and starch and reduced in situ rumen NDF digestibility. Abomasal inulin reduced the BUN concentration but did not affect milk yield or rumen NH₃, suggesting that RDP requirements are not affected by hindgut fermentation. Inulin shifted 23 g/d of N from urine to feces. However, based on fecal purine excretion, we estimated that only 8 g/d of the increased fecal N was due to increased fecal microbial output. Inulin reduced true digestibility of dietary protein or increased nonmicrobial as well as microbial endogenous losses. This latter effect may be an artifact of our experimental model that delivers easily fermented, soluble fiber to the small intestine. Normal dietary alterations to similarly increase large intestinal fermentation would probably arise from larger quantities of less rapidly digested carbohydrates. Increasing hindgut fermentation in practical diets should reduce manure NH₃ volatilization without impairing rumen fermentation, but the reduction is likely to be small.     

菊苣低聚果糖的研究与开发

菊苣低聚果糖是从菊苣根中提取的果聚糖,又被称为菊糖,是一种低聚果糖,菊糖不被有机体消化吸收而能被肠道微生物利用,进行肠内发酵,产生益生素作用和其他多种生理营养功能。在欧洲,功能性食品菊糖被广泛的应用于食品行业,特别是作为膳食纤维。本文主要介绍菊糖的成分、来源、消化后的生理功效以及作为膳食纤维的原因。     

膳食纤维通过调节肠道微生物及其代谢产物对动脉粥样硬化的影响研究进展

膳食纤维是一种不可被消化和吸收的碳水化合物聚合物,能够通过调节肠道微生物群的生长,促进肠道微生物区系的动态平衡,进而影响肠道微生物代谢产物如脂多糖、三甲胺N-氧化物、短链脂肪酸和胆汁酸的产生,达到调节宿主生理健康的目的.动脉粥样硬化是一种慢性炎症性疾病,其发生发展与脂质代谢紊乱和炎症反应关系密切.而肠道微生物及其代谢产...     

海藻多糖与肠道菌群相互作用研究进展

肠道菌群是寄居于宿主体内的共生微生物群体, 在维持机体健康及控制疾病发生等方面发挥着重要作用。海藻多糖是从海藻中提取出的一种具有生物活性的膳食纤维, 具有抗肿瘤、抗氧化、抗病毒、降血糖、免疫调节等多种活性。研究发现海藻多糖不能被人体消化酶降解, 但可以被肠道菌群降解和利用, 而海藻多糖又可以通过调节肠道菌群影响机体健康。本文综述了肠道菌群对海藻多糖的降解利用, 海藻多糖通过调节肠道菌群改善炎症性肠病、高血脂、糖尿病等疾病, 探讨了海藻多糖结构对肠道菌群的影响, 以期为海藻多糖与肠道菌群相互作用在改善人体健康方面的研究提供一定参考。     

菊粉对肠道健康的作用

近年来菊粉在肠道健康中的应用受到研究学者的广泛关注。菊粉作为优质益生元,能有效改善肠道微生态,提升肠道的生理功能、促进肠道对矿物质等营养物质的吸收和将有害残渣的排出。菊粉能对肠道的保健和慢性疾病的预防具有重要作用。本文综述了菊粉的性质、来源、营养价值及现状。从人体三大抵御疫病屏障和肠道微生态环境的角度阐述了肠道健康的重要性,主要探讨了菊粉如何增强胃肠功能、在肠道健康中的应用, 并对菊粉的未来发展前景进行了展望。     

Modulation of the human gut microbiota by phenolics and phenolic fiber‐rich foods

The gut microbiota plays a prominent role in human health. Alterations in the gut microbiota are linked to the development of chronic diseases such as obesity, inflammatory bowel disease, metabolic syndrome, and certain cancers. We know that diet plays an important role to initiate, shape, and modulate the gut microbiota. Long‐term dietary patterns are shown to be closely related with the gut microbiota enterotypes, specifically long‐term consumption of carbohydrates (related to Prevotella abundance) or a diet rich in protein and animal fats (correlated to Bacteroides). Short‐term consumption of solely animal‐ or plant‐based diets have rapid and reproducible modulatory effects on the human gut microbiota. These alterations in microbiota profile by dietary alterations can be due to impact of different dietary macronutrients, carbohydrates, protein, and fat, which have diverse modulatory effects on gut microbial composition. Food‐derived phenolics, which encompass structural variants of flavonoids, hydroxybenzoic acids, hydroxycinnamic acids, coumarins, stilbenes, ellagitannins, and lignans can modify the gut microbiota. Gut microbes have been shown to act on dietary fibers and phenolics to produce functional metabolites that contribute to gut health. Here, we discuss recent studies on the impacts of phenolics and phenolic fiber‐rich foods on the human gut microbiota and provide an insight into potential synergistic roles between their bacterial metabolic products in the regulation of the intestinal microbiota.     

微生物菊糖蔗糖酶及在食品中的应用研究进展

菊糖作为一种可溶性膳食纤维,具有良好的理化性质和重要的生理功能,因此,在食品中应用广泛。菊糖蔗糖酶能够以蔗糖为唯一底物,一步合成高分子质量的微生物菊糖。目前鉴定的菊糖蔗糖酶有15 种微生物来源,其中一种的晶体结构已经被解析。国内关于菊糖蔗糖酶的研究鲜有报道。本文对菊糖蔗糖酶的晶体结构和反应机理进行了综合分析。着重讨论了菊糖的链长调控以及菊糖蔗糖酶在生产高分子质量菊糖、低聚果糖、新型低聚糖和菊糖纳米材料方面的应用。最后,结合菊糖蔗糖酶的研究,探讨其发展趋势。