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International audience; Fermentation allows to preserve food in a sustainable way at a lower cost and contributes to the world food security. This method of preservation is currently very popular with a population in search of naturalness. Health virtues are also attributed to fermented foods because they contain living micro-organisms or specific macro- and micronutrients. Are these products, or the fermentation process, as such really beneficial to health?; La fermentation permet de conserver de manière durable les aliments à moindre coût dans de nombreux pays et participe grandement à la sécurité alimentaire mondiale. Ce mode de conservation est actuellement très prisé par une population en recherche de naturalité. Des vertus santé sont également attribuées aux aliments fermentés parce qu’ils contiennent des microorganismes vivants ou des macro-micronutriments spécifiques. Ces produits, très divers, ou le processus de fermentation en tant que tel sont-ils bénéfiques pour la santé ?

Introduction: Breastfeeding, because of the composition of humain milk, is recommended until six months of the child by the WHO. However, there has been a decrease of exclusive breastfeeding. New artificial milks appear, with a composition trying to get as close as possible to breast milk. Objective: The objective is to identify the effects of prebiotic and / or probiotic supplements in fomula-fed on the health of infantsMethods: Studies comparing groups of formula fed infants to formula fed infants supplemented with prebiotics and / or probiotics were selected from databases (PubMed, Cochrane, Google Scholar)Results: The growth and tolerance studies did not show any significant difference. A decrease in colic and crying is nevertheless reported. A large part of the studies show an improvement in the transit, by the modification of the intestinal flora, less constipation and infectious diarrhea. They also demonstrate an improvement in immunity and a decrease in allergies in children formula fed supplemented with probiotics and/or prebiotics. Conclusion: The effects of milk supplemented with prebiotics are beneficial for the immune system, on the onset of allergies. There are no observed effects on growth and the appearance of side effects. Milks supplemented with probiotics and / or probiotics therefore have beneficial effects compared to standard milk and have no side effects.; Introduction : l’allaitement maternel, de par la composition du lait, est préconisé jusqu’au six mois de l’enfant par l’OMS. Cependant, on observe une baisse de l’allaitement maternel exclusif. De nouveaux laits artificiels apparaissent, avec une composition essayant de se rapprocher au maximum du lait maternel.Objectif : l’objectif est d’identifier les effets des laits supplémentés en prébiotiques et/ou probiotiques sur la santé des nourrissons. Méthodes : des études comparant des groupes de nourrissons nourris au lait artificiel à des nourrissons nourris au lait artificiel supplémentés en prébiotiques et/ou probiotiques ont été sélectionnées sur des bases de données (PubMed, Cochrane, Google Scholar.Résultats : les études sur la croissance et la tolérance n’ont pas vraiment montré de différence significative. Une diminution de coliques et de pleurs est néanmoins constatée. Une grande partie des études démontrent une amélioration du transit, de par la modification de la flore intestinale, moins de constipation et diarrhée. Elles démontrent aussi une amélioration de l’immunité et diminution des allergies chez les enfants nourris au lait supplémentés par les probiotiques et/ou prébiotiques. Conclusion : Les effets des laits supplémentés en prébiotiques sont bénéfiques pour le système immunitaire, sur l’apparition d’allergies. Il n’y a d’effets constatés sur la croissance et l’apparition d’effets indésirables. Les laits supplémentés en probiotiques et/ou probiotique ont donc des effets bénéfiques par rapport aux laits standards et ne présentent pas d’effet indésirables.

Prebiotics are increasingly used as food supplements, especially in infant formulas, to modify the functioning and composition of the microbiota. However, little is currently known about the mechanisms of prebiotic recognition and transport by gut bacteria, while these steps are crucial in their metabolism. In this study, we established a new strategy to profile the specificity of oligosaccharide transporters, combining microbiomics, genetic locus and strain engineering, and state-of-the art metabolomics. We revisited the transporter classification database and proposed a new way to classify these membrane proteins based on their structural and mechanistic similarities. Based on these developments, we identified and characterized, at the molecular level, a fructooligosaccharide transporting phosphotransferase system, which constitutes a biomarker of diet and gut pathology. The deciphering of this prebiotic metabolization mechanism by a nonbeneficial bacterium highlights the controversial use of prebiotics, especially in the context of chronic gut diseases., Prebiotic oligosaccharides, such as fructooligosaccharides, are increasingly being used to modulate the composition and activity of the gut microbiota. However, carbohydrate utilization analyses and metagenomic studies recently revealed the ability of deleterious and uncultured human gut bacterial species to metabolize these functional foods. Moreover, because of the difficulties of functionally profiling transmembrane proteins, only a few prebiotic transporters have been biochemically characterized to date, while carbohydrate binding and transport are the first and thus crucial steps in their metabolization. Here, we describe the molecular mechanism of a phosphotransferase system, highlighted as a dietary and pathology biomarker in the human gut microbiome. This transporter is encoded by a metagenomic locus that is highly conserved in several human gut Firmicutes, including Dorea species. We developed a generic strategy to deeply analyze, in vitro and in cellulo, the specificity and functionality of recombinant transporters in Escherichia coli, combining carbohydrate utilization locus and host genome engineering and quantification of the binding, transport, and growth rates with analysis of phosphorylated carbohydrates by mass spectrometry. We demonstrated that the Dorea fructooligosaccharide transporter is specific for kestose, whether for binding, transport, or phosphorylation. This constitutes the biochemical proof of effective phosphorylation of glycosides with a degree of polymerization of more than 2, extending the known functional diversity of phosphotransferase systems. Based on these new findings, we revisited the classification of these carbohydrate transporters. IMPORTANCE Prebiotics are increasingly used as food supplements, especially in infant formulas, to modify the functioning and composition of the microbiota. However, little is currently known about the mechanisms of prebiotic recognition and transport by gut bacteria, while these steps are crucial in their metabolism. In this study, we established a new strategy to profile the specificity of oligosaccharide transporters, combining microbiomics, genetic locus and strain engineering, and state-of-the art metabolomics. We revisited the transporter classification database and proposed a new way to classify these membrane proteins based on their structural and mechanistic similarities. Based on these developments, we identified and characterized, at the molecular level, a fructooligosaccharide transporting phosphotransferase system, which constitutes a biomarker of diet and gut pathology. The deciphering of this prebiotic metabolization mechanism by a nonbeneficial bacterium highlights the controversial use of prebiotics, especially in the context of chronic gut diseases.

International audience; The aim of this systematic review was to assess the effect of fructo-oligosaccharide supplementation on glucose homeostasis. The search process was based on the selection of publications listed in the Pubmed-Medline database until April 2016 to identify studies evaluating the impact of short-chain fructo-oligosaccharides or oligofructose on glucose homeostasis. Twenty-nine trials were included in the systematic review and the meta-analysis was performed on twelve of these papers according to the inclusion criteria. Fasting blood concentrations of glucose and insulin were selected as pertinent criteria of glucose homeostasis for the meta-analysis. The consumption of fructo-oligosaccharides decreased fasting blood glycaemia levels, whatever the metabolic status (healthy, obese or diabetic) and diet (low-fat or high-fat) throughout the experiment. This reduction was linear with prebiotic dose (from 0 to 13% of the feed). Fasting insulinaemia also decreased linearly with fructo-oligosaccharide supplementation but the reduction was only significant in rodents fed a low-fat diet. Potential underlying mechanisms include gut bacterial fermentation of fructo-oligosaccharides to short-chain fatty acids (SCFA) and bacterial modulation of bile acids, both interacting with host metabolism. This systemic review, followed by the meta-analysis, provides evidence that fructo-oligosaccharide supplementation has a significant effect on glucose homeostasis whatever the health status and diet consumed by animals.

Dans une série d’études menées sur le modèle porcin, nous avons mis en évidence l’impact d’une alimentation déséquilibrée (maternelle ou post-sevrage) durant la période prénatale et/ou postnatale sur la progéniture, en particulier sur la lipidémie et la cholestérolémie plasmatique, l’activité du microbiote intestinal, les comportements et la plasticité neurocognitive, ainsi que le métabolisme et la neurotransmission de zones cérébrales impliquées dans le circuit hédonique et la cognition. Au travers d’études précliniques visant à décrire les effets de traitements pré- ou probiotiques, nous confirmons que des modifications de la composition du microbiote et de son activité métabolique induites par l’alimentation périnatale (alimentation maternelle et formules infantiles) sont durables jusqu’au stade adulte où elles sont également associées à des changements de la physiologie intestinale et du métabolisme de l’adulte. L’alimentation maternelle et du nouveau-né est un levier d’action majeur pour agir via le microbiote sur les réponses comportementales et assurer un développement optimal du nouveau-né et la santé du futur adulte., In a series of studies performed in the pig model, we described the impact of deleterious nutrition (maternal or post-weaning) during the prenatal and/or postnatal period on the progeny, and especially on lipidemia and cholesterolemia, intestinal microbiota activity, the behavior and neurocognitive plasticity, as well as metabolism and neurotransmission in brain areas involved in cognition and reward. Through preclinical studies aimed at describing the effects of pre- or probiotic treatments, we confirmed that the changes in the composition and metabolic activity of the microbiota induced by the perinatal nutrition (maternal diet and infant formula) are persistent until the adult age, where they are associated with changes of intestinal physiology and metabolism. The maternal and newborn nutrition is a major target to act, via the intestinal microbiota, on the behavioral responses and guarantee an optimal neonatal development and adult health.

© 2017 American Dairy Science Association Obesity is characterized by altered gut homeostasis, including dysbiosis and increased gut permeability closely linked to the development of metabolic disorders. Milk oligosaccharides are complex sugars that selectively enhance the growth of specific beneficial bacteria in the gastrointestinal tract and could be used as prebiotics. The aim of the study was to demonstrate the effects of bovine milk oligosaccharides (BMO) and Bifidobacterium longum ssp. infantis (B. infantis) on restoring diet-induced obesity intestinal microbiota and barrier function defects in mice. Male C57/BL6 mice were fed a Western diet (WD, 40% fat/kcal) or normal chow (C, 14% fat/kcal) for 7 wk. During the final 2 wk of the study, the diet of a subgroup of WD-fed mice was supplemented with BMO (7% wt/wt). Weekly gavage of B. infantis was performed in all mice starting at wk 3, yet B. infantis could not be detected in any luminal contents when mice were killed. Supplementation of the WD with BMO normalized the cecal and colonic microbiota with increased abundance of Lactobacillus compared with both WD and C mice and restoration of Allobaculum and Ruminococcus levels to that of C mice. The BMO supplementation reduced WD-induced increase in paracellular and transcellular flux in the large intestine as well as mRNA levels of the inflammatory marker tumor necrosis factor α. In conclusion, BMO are promising prebiotics to modulate gut microbiota and intestinal barrier function for enhanced health.

Mounting evidence shows that the gut microbiota, an important player within the gut-brain communication axis, can affect metabolism, inflammation, brain function and behavior. Interestingly, gut microbiota composition is known to be altered in patients with metabolic syndrome (MetS), who also often display neuropsychiatric symptoms. The use of prebiotics, which beneficially alters the microbiota, may therefore be a promising way to potentially improve physical and mental health in MetS patients. This hypothesis was tested in a mouse model of MetS, namely the obese and type-2 diabetic db/db mice, which display emotional and cognitive alterations associated with changes in gut microbiota composition and hippocampal inflammation compared to their lean db/+ littermates. We assessed the impact of chronic administration (8 weeks) of prebiotics (oligofructose) on both metabolic (body weight, food intake, glucose homeostasis) and behavioral (increased anxiety-like behavior and impaired spatial memory) alterations characterizing db/db mice, as well as related neurobiological correlates, with particular attention to neuroinflammatory processes. Prebiotic administration improved excessive food intake and glycemic dysregulations (glucose tolerance and insulin resistance) in db/db mice. This was accompanied by an increase of plasma anti-inflammatory cytokine IL-10 levels and hypothalamic mRNA expression of the anorexigenic cytokine IL-1β, whereas unbalanced mRNA expression of hypothalamic orexigenic (NPY) and anorexigenic (CART, POMC) peptides was unchanged. We also detected signs of improved blood-brain-barrier integrity in the hypothalamus of oligofructose-treated db/db mice (normalized expression of tight junction proteins ZO-1 and occludin). On the contrary, prebiotic administration did not improve behavioral alterations and associated reduction of hippocampal neurogenesis displayed by db/db mice, despite normalization of increased hippocampal IL-6 mRNA expression. Of note, we found a relationship between the effect of treatment on dentate gyrus neurons and spatial memory. These findings may prove valuable for introducing novel approaches to treat some of the comorbidities associated with MetS.

Probiotics are live microorganisms, which when administered in adequate amounts confer a health benefit on the host. Bacillus probiotic strains are not able to colonize the gut, and are considered as transient residents of the microbiota. Prebiotic are non-digestible food ingredients that could stimulate growth of bacteria in the gut. This work investigates the in vitro effect of a prebiotic isomaltooligosaccharide (IMOS) on the growth of a probiotic strain Bacillus subtilis. This study highlights the ability of the strain to use IMOS as unique carbon source. A comparative proteomic analysis investigates the main enzymes implicated in the prebiotic metabolism, and biomarkers possibly involved in probiotic effects. This preliminary work, which studies the synbiotic association between a probiotic and a prebiotic, will lead to in vivo assays. Beneficial effects of probiotic Bacilli, mainly modulation of intestinal immune system, result from interaction between bacterial cell-wall molecules and intestinal cells. The molecular origin of immunomodulatory mechanisms are poorly understood, while understanding is needed to optimize the use of probiotics. A second part of this work consists in comparing the structure of a molecular cell-wall component named lipoteichoic acids (LTA) from three Bacillus probiotic, a molecular cell-wall component of Gram positive bacteria, and their immunological activity. A structural study, using biochemical determinations and NMR spectroscopic analysis, highlights the structural diversity between LTAs from different Bacillus species. The key role of D-alanine substituents in the biological activity of these bacterial antigens has been demonstrated.; Les probiotiques sont des microorganismes vivants qui, lorsqu’ils sont ingérés en quantité adéquate, peuvent exercer des propriétés bénéfiques sur la santé de l’hôte. Les souches de Bacillus utilisées en tant que probiotiques ne sont pas colonisatrices du tractus intestinal, mais sont des résidents transitoires du microbiote. Ce travail fait l’investigation in vitro de l’association, qualifiée de synbiotique, entre une souche probiotique de Bacillus subtilis et une source carbonée prébiotique, composé alimentaire peu digéré par les enzymes intestinales mais utilisable par les bactéries dans l’intestin. L’étude de cette association met en évidence la capacité de la souche à utiliser les isomaltooligosaccharides (IMOS) prébiotiques comme unique substrat carboné. L’effet positif de ce substrat sur la tolérance à la bile de la souche a été démontré in vitro. Les résultats d’une analyse protéomique faisant l’étude des enzymes clés impliquées dans le métabolisme des IMOS, ainsi que d’autres biomarqueurs d’intérêt probiotique, sont en cours d’exploitation. Ce travail préliminaire d’investigation de l’association synbiotique entre les IMOS prébiotiques et la souche probiotique B. subtilis, aboutira à des essais in vivo. Les effets bénéfiques des probiotiques du genre Bacillus, notamment au niveau de la modulation du système immunitaire, résultent de l’interaction entre les molécules de la surface bactérienne et les cellules de l’intestin. Les mécanismes moléculaires à l’origine de l’immunomodulation sont mal connus, alors que leur compréhension est nécessaire à l’optimisation de l’utilisation du probiotique. Un deuxième volet de ce travail concerne la comparaison des structures d’entités moléculaires de surface de trois Bacilli probiotiques, les acides lipotéichoïques (LTAs), et leurs activités immunologiques respectives. Une étude structurale des LTAs par des méthodes biochimiques et par RMN a permis de mettre en évidence la diversité structurale au sein du même genre Bacillus. Le rôle clé de la D-alanine dans l’activité biologique de ces antigènes bactériens a été démontré.

Rotifers (Brachionus plicatilis), commonly used at first feeding in commercial fish hatcheries, carry a large bacteria load. Because they are relatively poor in essential fatty acids, it is common practice to enrich them with fatty acids, including arachidonic acid (AA). This study aims to determine whether prey enrichment with AA may act as a prebiotic and modify the microbial community composition either in AA-enriched rotifer cultures or in larval-rearing water using winter flounder (Pseudopleuronectes americanus) as a larval fish model. AA enrichment modified the bacterial community composition in both the rotifer culture tanks and the larval-rearing tanks. We observed an increase in the number of cultivable bacteria on TCBS (thiosulfate-citrate-bile salts-sucrose) agar, used as a proxy for the abundance of Vibrio sp. The results suggest that AA may also play an indirect role in larval health., Les rotifères (Brachionus plicatilis), fréquemment utilisés comme première source alimentaire dans les piscicultures commerciales, portent une charge bactérienne importante. Parce qu’ils sont relativement pauvres en acides gras essentiels, il est de pratique courante de les enrichir en acides gras, notamment en acide arachidonique (AA). Cette étude vise à déterminer si l’enrichissement des proies à l’AA peut agir comme prébiotique et modifier la composition de la communauté microbienne non seulement dans les cultures de rotifères enrichies à l’AA, mais aussi dans l’eau d’élevage des larves, en utilisant la plie rouge (Pseudopleuronectes americanus) comme modèle de larves de poisson. L’enrichissement en AA a modifié la composition de la communauté microbienne tant dans les bassins de culture de rotifères que dans les bassins d’élevage des larves. Un accroissement du nombre de bactéries cultivables sur la gélose TCBS (thiosulfate – citrate – sels biliaires – sucrose), utilisée pour estimer l’abondance de Vibrio sp., a également été observé. Les résultats suggèrent que l’AA peut aussi jouer un rôle indirect dans la santé des larves

We read with great interest the recent study by Dewulf and coworkers1 reporting encouraging results on a prebiotic-based dietary intervention trial in obese patients. This work enlightens that even subtle changes in the gut microbiota may influence the metabolomic signature both inside and outside the gut. Interplay among diet, immunity and microbial and host metabolism results in a complex multidirectional signalling that is critical in the maintenance of a healthy gut functionality, reducing risks for inflammatory bowel diseases and metabo-inflammation states associated with obesity.2 ,3 In parallel, the ‘omics’ era has produced many observations associated with disease states,4 and the correlation among the presence, absence or specific ratios of certain bacterial phyla, orders or genera can be considered as a strategy to directly or indirectly manipulate the microbiome. However, a clear causal molecular link between a specific microbial community and a specific metabolic or immune profile is …

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10 páginas, 2 figuras. Les applications alimentaires du chitosane es el capítulo 8 del libro., Food application of chitosan and its derivatives. Nowadays consumers demand microbiologically safer foods with longer product shelf life and with environmentally friendly packaging. This is forcing the industry to develop new food-processing and packaging strategies; such as seeking new natural additives and developing bioactive films, which are both edible and biodegradable, for food conservation. Chitosan seems to be a potential alternative additive for food application, since it is a natural compound obtained from by-products that can be incorporated into the food product or as edible films, and due to its functional properties, namely protecting the food and benefiting the consumer after its consumption, Les consommateurs demandent des aliments de plus en plus sécurisés possédant de nouvelles fonctions (domaine des « alicaments »), avec des durées de consommation plus longues et des emballages qui respectent l’environnement. Ceci oblige le secteur industriel à développer de nouvelles stratégies pour la préparation et le packaging des aliments. Les recherches actuelles s’orientent non seulement sur l’incorporation d’additifs et d’ingrédients naturels fonctionnels, mais également sur le développement de films biocompatibles. Le chitosane semble être une alternative prometteuse dans le domaine alimentaire car c’est un produit naturel biocompatible et biodégradable obtenu à partir de co-produits. Le chitosane peut être soit incorporé directement dans les produits pour jouer un rôle fonctionnel ou d’additif, soit être utilisé comme film protecteur., Ministère des Affaires Etrangères et de la Coopération d’Espagne pour l’aide concédée A/011205/07 dans le programme de coopération inter-universitaire et de recherche scientifique AECI-MEC 2007

International audience; Catala-Gregori, P., Mallet, S., Travel, A., Orengo, J. and Lessire, M. 2008. Efficiency of a prebiotic and a plant extract alone or in combination on broiler performance and intestinal physiology. Can. J. Anim. Sci. 88: 623-629. A 36-d trial was conducted to evaluate two potential alternatives to antibiotic growth promoters in broilers. The products tested were a prebiotic (PROFEED (R)) and a plant extract (XTRACT (TM)). Ross mate broiler performance and digestive tract function responses were studied. To evaluate the effect of these potential alternatives alone or in combination, seven diets were tested: positive control avilamycin 10 ppm (PC);negative control antibiotic-free (NC); NC+PROFEED (R) 600 ppm (P); NC+XTRACT (TM) 100 ppm (X); NC+PROFEED (R)/XTRACT (TM) 600/100 ppm (XPH); NC+PROFEED (R)/XTRACT (TM) 450/75 ppm (XPM); NC+PROFEED (R)/XTRACT (TM) 300/50 ppm (XPL). From 22 to 36 d of age, body weight gain (BWG) was improved by P, X, and XPM compared with NC (P < 0.05). Throughout the trial, broilers fed PC, P, X and XPL had a better feed conversion ratio (FCR) than those fed NC (P < 0.1). No relevant negative effect was observed for the parameters relative to the digestive tract function:ileal histomorphometry, anaerobic sulphite-reducing bacteria count (ASR), intestinal and caecal pH, caecal volatile fatty acids production (VFA) and litter score (LS). With the higher mixture dose (XPH), no improvement in broiler performance was observed, suggesting no synergistic effect of the two additives.

It is claimed that bifidobacteria have several health-promoting effects. To increase the amount of bifidobacteria in the colon the concept of probiotics and/or prebiotics can be applied. Bifidobacterium adolescentis is one of the main species of bifidobacteria in the gastro-intestinal tract of human adults. B. adolescentis is able to degrade a wide range of oligosaccharides and a number of glycosyl hydrolases have been characterized in detail. The hydrolytic activity of the glycosyl hydrolases from B. adolescentis toward prebiotics like arabinoxylan-oligosaccharides, isomalto-oligosaccharides, arabinogalactan, and sucrose-based oligosaccharides (raffinose, stachyose, and fructo-oligosaccharides) is reviewed. Alternatively, some of these glycosyl hydrolases are able to catalyze transglycosylation, which allows them to elongate oligosaccharides and to prepare potentially prebiotic oligosaccharides. Such oligosaccharides might be used to influence the microbial composition in the more distal parts of the colon. In nature, not all enzyme-substrate encounters are transglycosylating. So, the hydrolytic activity of the enzyme makes the oligosaccharide elongation less efficient than desired. Site-directed mutagenesis was applied to improve the transglycosylation reaction of the $\alpha$-galactosidase from B. adolescentis., Les glycosyl hydrolases de Bifidobacterium adolescentis DSM20083. Il est affirmé que les bifidobactéries ont des propriétés bénéfiques sur la santé. Pour augmenter la teneur en bifidobactéries au niveau du colon, le concept de probiotiques et/ou prébiotiques peut être appliqué. Bifidobacterium adolescentis est l'une des principales espèces de bifidobactéries dans le tractus gastro-intestinal des adultes. Certaines des glycosyl hydrolases de B. adolescentis ont été caractérisées en détail et elles semblent dégrader un large éventail d'oligosaccharides. L'activité d'hydrolyse des glycosyl hydrolases de B. adolescentis envers des prébiotiques tels que les arabino-xylanes, isomalto-oligosaccharides, arabino-galactanes et les oligosaccharides contenant du saccharose (raffinose, stachyose et fructo-oligosaccharides) est passée en revue. De plus, certaines de ces glycosyl hydrolases peuvent être utilisées pour préparer des oligosaccharides prébiotiques potentiels par transglycosylation, ce qui permet d'allonger les oligosaccharides. De tels oligosaccharides peuvent être utilisés pour influencer la composition microbienne au niveau des parties plus distales du colon. Les produits de rencontre enzymes-substrates ne sont pas tous transglycosylés naturellement et l'activité d'hydrolyse de l'enzyme entraîne une élongation de l'oligosaccharide moindre que celle désirée. La mutagenèse dirigée a été appliquée pour améliorer la réaction de transglycosylation de l'$\alpha$-galactosidase de B. adolescentis.

International audience; INTRODUCTION: Soy products are of particular interest because of their potential health benefits in a range of hormonal conditions, such as osteoporosis, due to their high content in phytoestrogens. Because equol, the main metabolite from soy isoflavones, is thought to be powerful, the present study was designated to evaluate the bone-sparing effects of equol by either providing the molecule through the diet or by eliciting its endogenous production by modulating intestinal microflora by short-chain fructooligosaccharides (sc-FOS) or live microbial (Lactobacillus casei) together with daidzein, its precursor. METHODS: A comparison with daidzein and genistein was also performed. Rats (3 months old) were ovariectomised (OVX) or sham-operated (SH). Ovariectomised rats were randomly assigned to six experimental diets for 3 months: a control diet (OVX), the control diet supplemented with either genistein (G), or daidzein (D), or equol (E) at the level of 10 microg/g body weight/d. The remaining OVX rats were given daidzein at the dose of 10 mug/g body weight/d, simultaneously with short-chain FOS (Actilight, Beghin-Meiji) (D+FOS) or Lactobacillus casei (Actimel, Danone) (D+L). The SH rats were given the same control diet as OVX. RESULTS: Genistein, daidzein or equol exhibited a bone sparing effect. Indeed, total femoral bone mineral density (BMD) was significantly enhanced (compared to that of OVX rats), as was the metaphyseal compartment. Bone strength was improved by E consumption, but not by genistein or daidzein given alone. As far as the FOS diet is concerned, the addition of prebiotics significantly raised efficiency of the daidzein protective effect on both femoral BMD and mechanical properties. The effects of lactobacillus were similar, except that the increase in metaphyseal-BMD was not significant. CONCLUSION: In conclusion, long-term equol consumption, like genistein and daidzein, in the ovariectomized rat, provides bone sparing effects. Adding indigestible sugars, such as FOS or live microbial as L. casei, in the diet significantly improves daidzein protective effects on the skeleton.