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Humans often show variable responses to dietary, prebiotic, and probiotic interventions. Emerging evidence indicates that the gut microbiota is a key determinant for this population heterogeneity. Here, we provide an overview of some of the major computational and experimental tools being applied to critical questions of microbiota-mediated personalized nutrition and health. First, we discuss the latest advances in in silico modeling of the microbiota-nutrition-health axis, including the application of statistical, mechanistic, and hybrid artificial intelligence models. Second, we address high-throughput in vitro techniques for assessing interindividual heterogeneity, from ex vivo batch culturing of stool and continuous culturing in anaerobic bioreactors, to more sophisticated organ-on-a-chip models that integrate both host and microbial compartments. Third, we explore in vivo approaches for better understanding of personalized, microbiota-mediated responses to diet, prebiotics, and probiotics, from nonhuman animal models and human observational studies, to human feeding trials and crossover interventions. We highlight examples of existing, consumer-facing precision nutrition platforms that are currently leveraging the gut microbiota. Furthermore, we discuss how the integration of a broader set of the tools and techniques described in this piece can generate the data necessary to support a greater diversity of precision nutrition strategies. Finally, we present a vision of a precision nutrition and healthcare future, which leverages the gut microbiota to design effective, individual-specific interventions.

Prebiotic human milk oligosaccharides (HMOs) are found in human milk, which are not digested by infants but are metabolized by beneficial gut bacteria. We determined the ability of 57 bacterial strains within the Family Lactobacillaceae and genera Bifidobacterium and Bacteroides and potentially pathogenic bacteria to ferment the HMOs 2'-fucosyllactose, 3-fucosyllactose, and difucosyllactose. In addition, prebiotic galacto-oligosaccharides (GOS), lactose, fucose, and glucose were evaluated as carbon sources for these bacterial strains. Bacterial growth was monitored using the automatic Bioscreen C system. Only certain bifidobacteria, such as Bifidobacterium longum subsp. infantis and Bifidobacterium bifidum, as well as Bacteroides fragilis, Bacteroides vulgatus, and Bacteroides thetaiotaomicron utilized the studied HMOs as their sole carbon source, whereas almost all studied bacterial strains were able to utilize GOS, lactose, and glucose. The selectivity in utilization of HMOs by only certain bacteria can be advantageous by promoting beneficial microbes but not supporting the harmful pathogens in contrast to other less selective prebiotics.

The successful development of probiotic foods and dietary supplements rests on three pillars; each with their specific challenges and opportunities. First, strain production; this depends on selecting the right strain with promising technological properties and safety profile. Further the manufacturing of the strain in a stable format at sufficiently high yield, following regulatory and customer requirements on culture media ingredients and other processing aids. The second pillar are the preclinical and clinical studies to document that the strain is a probiotic and exerts a health benefit on the host, the consumer. Especially when aiming for a regulator approved health claim, clinical studies need to be thoroughly performed; following appropriate ethical, scientific and regulatory guidelines. Finally, the probiotic will need to be incorporated in a product that can be brought to the consumer; a dietary supplement or a functional food. Because of the live nature of probiotics, specific challenges may need to be dealt with. Although experience from other strains is helpful in the process, the development is strain specific. Commercialisation and marketing of probiotics are strictly but differently regulated in most jurisdictions; defining what can and cannot be claimed., Successful development of probiotics relies on production of a probiotic strain, documenting it's health benefits and inclusion in a consumer product.

Aims: Gut microbiota significantly impacts human health and is influenced by dietary changes. We evaluated the effects of diets naturally rich in polyphenols (PP) and/or long-chain n-3 polyunsaturated fatty acids (LCn3) on microbiota composition in an ancillary analysis of a randomized controlled trial in individuals at high cardiometabolic risk. Methods: Seventy-eight individuals with high waist circumference and at least one additional component of the metabolic syndrome were randomized to an isoenergetic 8-week diet: (a) low LCn3 and PP; (b) high LCn3; (c) high PP; or (d) high LCn3 and PP. Microbiota analysis was performed on feces collected before and after the intervention. DGGE analysis of the predominant bacteria, Eubacterium rectale and Blautia coccoides group (Lachnospiraceae, EREC), Clostridium leptum (Ruminococcaceae, CLEPT), Bacteroides spp., Bifidobacteria, and Lactobacillus group was performed. A quantitative real-time PCR was performed for the same group, additionally including Atopobium cluster (Coriobatteriaceae). Before and after the intervention, participants underwent a 75 g OGTT and a high-fat test meal to evaluate glucose and lipid response. Results: Adherence to the four diets was optimal. PP significantly increased microbial diversity (p = 0.006) and CLEPT (p = 0.015), while it reduced EREC (p = 0.044). LCn3 significantly increased the numbers of Bifidobacteria (p = 0.041). Changes in CLEPT numbers correlated with changes in early insulin secretion (r = 0.263, p = 0.030). Changes in Atopobium numbers correlated with postprandial triglycerides in plasma (r = 0.266, p = 0.026) and large VLDL (r = 0.313, p = 0.009), and cholesterol in large VLDL (r = 0.319, p = 0.008). Conclusions: Diets naturally rich in PP or LCn3 influenced gut microbiota composition in individuals at high cardiometabolic risk. These modifications were associated with changes in glucose/lipid metabolism.

Insoluble residue (INS) is a lignin-rich fraction of brewer's spent grain (BSG) that also contains β-glucan and arabinoxylan, the major constituents of dietary fiber. We investigated the effects of INS in diet-induced obese mice in terms of lipid metabolism and metabolic diseases. Male mice (C57bl6) were fed a high-fat diet (HFD), a HFD + 20% INS, a HFD + 20% cellulose (CEL), a HFD with a combination of 20% INS-CEL (1:1), or a control diet for 14 weeks. Insulin and glucose tolerance tests were performed after 12 weeks. Fasting plasma lipids, bile acid, and fecal bile acid were measured after 14 weeks of feeding, and tissues were collected for gene expression analysis. Body weight gain was significantly reduced with all fibers, but only INS and INS-CEL decreased fasting plasma low-density lipoprotein cholesterol and total cholesterol compared to HFD. CEL and INS-CEL significantly improved insulin resistance. Fecal bile acids were significantly increased by all fibers, but there was no change in plasma bile acid. Clostridium leptum was increased with all fibers, but universal bacterial diversity was only with INS and INS-CEL. In addition, INS significantly increased the abundance of Bacteriodes, while CEL decreased Atopobium and Lactobacillus. INS feeding significantly upregulated various genes of cholesterol and bile acid metabolism, such as Srebp2, Hmgcr, Ldlr, Cyp7a1, Pparα, Fxr, and Pxr, in the liver. INS, INS-CEL, and CEL significantly attenuated liver steatosis. Our results suggest that INS from BSG induced beneficial systemic changes in mice via gut microbiota, bile acids, and gene expression in the liver.

The growing worldwide epidemic of obesity and associated metabolic health comorbidities has resulted in an urgent need for safe and efficient nutritional solutions. The research linking obesity with gut microbiota dysbiosis has led to a hypothesis that certain bacterial strains could serve as probiotics helping in weight management and metabolic health. In the search for such strains, the effect of Bifidobacterium animalis subsp. lactis 420 (B420) on gut microbiota and metabolic health, and the mechanisms of actions, has been investigated in a variety of in vitro, pre-clinical, and clinical studies. In this review, we aim to highlight the research on B420 related to obesity, metabolic health, and the microbiota. Current research supports the hypothesis that gut dysbiosis leads to an imbalance in the inflammatory processes and loss of epithelial integrity. Bacterial components, like endotoxins, that leak out of the gut can invoke low-grade, chronic, and systemic inflammation. This imbalanced state is often referred to as metabolic endotoxemia. Scientific evidence indicates that B420 can slow down many of these detrimental processes via multiple signaling pathways, as supported by mechanistic in vitro and in vivo studies. We discuss the connection of these mechanisms to clinical evidence on the effect of B420 in controlling weight gain in overweight and obese subjects. The research further indicates that B420 may improve the epithelial integrity by rebalancing a dysbiotic state induced by an obesogenic diet, for example by increasing the prevalence of lean phenotype microbes such as Akkermansia muciniphila. We further discuss, in the context of delivering the health benefits of B420: the safety and technological aspects of the strain including genomic characterization, antibiotic resistance profiling, stability in the product, and survival of the live probiotic in the intestine. In summary, we conclude that the clinical and preclinical studies on metabolic health suggest that B420 may be a potential candidate in combating obesity; however, further clinical studies are needed.

The effects of gut microbiota on the central nervous system, along its possible role in mental disorders, have received increasing attention. Here we investigated differences in fecal microbiota between 28 patients with first-episode psychosis (FEP) and 16 healthy matched controls and explored whether such differences were associated with response after up to 12 months of treatment. Numbers of Lactobacillus group bacteria were elevated in FEP-patients and significantly correlated with severity along different symptom domains. A subgroup of FEP patients with the strongest microbiota differences also showed poorer response after up to 12 months of treatment. The present findings support the involvement of microbiota alterations in psychotic illness and may provide the basis for exploring the benefit of their modulation on treatment response and remission. (C) 2017 Elsevier B.V. All rights reserved.

Feather degrading bacteria from birds' nests were characterized to find safe bacterial strains that could be utilized to convert feathers into soluble form and bacterial biomass for feed purposes. Of all tested 571 isolates 122 were keratinolytic. Partial sequencing of the 16S rRNA gene revealed that the keratinolytic isolates represented Proteobacteria (genera Pseudomonas and Stenotrophomonas) and Firmicutes (genera Bacillus, Exiguobacterium, Paenibacillus, Rummeliibacillus, and Sporosarcina). Bacillus cereus group and gram-negative bacterial isolates were not further characterized due to safety concerns related to potential pathogenicity or potential exposure of animals or workers to endotoxins (lipopolysaccharide part of the gram-negative cell wall). Keratinolytic strains showed clear differences in their ability to solubilize feathers with feather weight losses up to 30%. Amino acid composition of feather hydrolysates shifted from feather composition towards more bacterial-like composition. Especially the levels of lysine could be increased in the feather hydrolysate with bacterial fermentation. Feathers can be effectively hydrolyzed with non-pathogenic bacteria without any additional nutrients. The resulting feather hydrolysate is easier to digest than feather material and it has an improved amino acid composition regarding some limiting amino acids. The amino acid content of the final product can be tailored by varying the fermentation time and thus the ratio of bacterial cells to the feather hydrolysate.

Brewer's spent grain (BSG) is the major side-stream from brewing. As BSG is rich in dietary fiber and protein, it could be used in more valuable applications, such as nutritional additives for foods. Our aim was to elucidate whether an insoluble lignin-rich fraction (INS) from BSG is metabolized by mice gut microbiota and how it affects the microbiota. Our results indicated that lignin was partially degraded by the gut microbiota, degradation products were absorbed, and finally excreted in urine. Therefore, they contribute to the phenolic pool circulating in the mammalian body, and may have systemic effects on health. In addition, the effects of the test diets on the microbiota were significant. Most interestingly, diversities of predominant cecal and fecal bacteria were higher after the intervention diet containing INS than after the intervention diet containing cellulose. Since low fecal bacterial diversity has been linked with numerous diseases and disorders, the diversity increasing ability opens very interesting perspectives for the future.

Gut microbiota significantly impacts human health and is influenced by dietary changes. We evaluated the effects of diets naturally rich in polyphenols (PP) and/or long-chain n-3 polyunsaturated fatty acids (LCn3) on microbiota composition in an ancillary analysis of a randomized controlled trial in individuals at high cardiometabolic risk.Seventy-eight individuals with high waist circumference and at least one additional component of the metabolic syndrome were randomized to an isoenergetic 8-week diet: (a) low LCn3 and PP; (b) high LCn3; (c) high PP; or (d) high LCn3 and PP. Microbiota analysis was performed on feces collected before and after the intervention. DGGE analysis of the predominant bacteria, Eubacterium rectale and Blautia coccoides group (Lachnospiraceae, EREC), Clostridium leptum (Ruminococcaceae, CLEPT), Bacteroides spp., Bifidobacteria, and Lactobacillus group was performed. A quantitative real-time PCR was performed for the same group, additionally including Atopobium cluster (Coriobatteriaceae). Before and after the intervention, participants underwent a 75 g OGTT and a high-fat test meal to evaluate glucose and lipid response.Adherence to the four diets was optimal. PP significantly increased microbial diversity (p = 0.006) and CLEPT (p = 0.015), while it reduced EREC (p = 0.044). LCn3 significantly increased the numbers of Bifidobacteria (p = 0.041). Changes in CLEPT numbers correlated with changes in early insulin secretion (r = 0.263, p = 0.030). Changes in Atopobium numbers correlated with postprandial triglycerides in plasma (r = 0.266, p = 0.026) and large VLDL (r = 0.313, p = 0.009), and cholesterol in large VLDL (r = 0.319, p = 0.008).Diets naturally rich in PP or LCn3 influenced gut microbiota composition in individuals at high cardiometabolic risk. These modifications were associated with changes in glucose/lipid metabolism.

The development of prebiotic fibers requires fast high-throughput screening of their effects on the gut microbiota. We demonstrated the applicability of a mictotiter plate in the in vitro fermentation models for the screening of potentially-prebiotic dietary fibers. The effects of seven rye bran-, oat- and linseed-derived fiber preparations on the human fecal microbiota composition and short-chain fatty acid production were studied. The model was also used to study whether fibers can alleviate the harmful effects of amoxicillin-clavulanate on the microbiota. The antibiotic induced a shift in the bacterial community in the absence of fibers by decreasing the relative amounts of Bifidobacteriaceae, Bacteroidaceae, Prevotellaceae, Lachnospiraceae and Ruminococcaceae, and increasing proteobacterial Sutterilaceae levels from 1% to 11% of the total microbiota. The fermentation of rye bran, enzymatically treated rye bran, its insoluble fraction, soluble oat fiber and a mixture of rye fiber:soluble oat fiber:linseed resulted in a significant increase in butyrate production and a bifidogenic effect in the absence of the antibiotic. These fibers were also able to counteract the negative effects of the antibiotic and prevent the decrease in the relative amount of bifidobacteria. Insoluble and soluble rye bran fractions and soluble oat fiber were the best for controlling the level of proteobacteria at the level below 2%.

In this work, six common stainless steel grades were compared with respect to ennoblement characteristics, corrosion performance and tendency to biofouling in brackish sea water in a pilot-scale cooling water circuit. Two tests were performed, each employing three test materials, until differences between the materials were detected. Open circuit potential (OCP) was measured continuously in situ. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements were conducted before and after the tests. Exposed specimens were further subjected to examinations by scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS), and the biofouling was studied using epifluorescence microscopy, quantitative polymerase chain reaction (qPCR) and high-throughput sequencing (HTP sequencing). The results revealed dissimilarities between the stainless steel grades in corrosion behaviour and biofouling tendency. The test material that differed from the most of the other studied alloys was grade EN 1.4162. It experienced fastest and most efficient ennoblement of OCP, its passive area shrank to the greatest extent and the cathodic reaction was accelerated to a significant degree by the development of biofilm. Furthermore, microbiological analyses revealed that bacterial community on EN 1.4162 was dominated by Actinobacteria, whereas on the other five test materials Proteobacteria was the main bacterial phylum.

The human oro-gastrointestinal (GI) tract is a complex system, consisting of oral cavity, pharynx, oesophagus, stomach, small intestine, large intestine, rectum and anus, which all together with the accessory digestive organs constitute the digestive system. The function of the digestive system is to break down dietary constituents into small molecules and then absorb these for subsequent distribution throughout the body. Besides digestion and carbohydrate metabolism, the indigenous microbiota has an important influence on host physiological, nutritional and immunological processes, and commensal bacteria are able to modulate the expression of host genes that regulate diverse and fundamental physiological functions. The main external factors that can affect the composition of the microbial community in generally healthy adults include major dietary changes and antibiotic therapy. Changes in some selected bacterial groups have been observed due to controlled changes to the normal diet e.g. high-protein diet, high-fat diet, prebiotics, probiotics and polyphenols. More specifically, changes in the type and quantity of non-digestible carbohydrates in the human diet influence both the metabolic products formed in the lower regions of the GI tract and the bacterial populations detected in faeces. The interactions between dietary factors, gut microbiota and host metabolism are increasingly demonstrated to be important for maintaining homeostasis and health. Therefore the aim of this review is to summarise the effect of diet, and especially dietary interventions, on the human gut microbiota. Furthermore, the most important confounding factors (methodologies used and intrinsic human factors) in relation to gut microbiota analyses are elucidated.

The food industry, including the meat industry, is currently looking for natural preservatives to prevent the growth of harmful microbes in foods. The potential of plant-derived antimicrobial extracts to increase the shelf life and to delay the microbiological spoilage of marinated broiler chicken cuts in modified atmosphere packages during cold storage was investigated in this study. We evaluated the impact of aqueous ethanolic extracts of Finnish sea buckthorn berries and lingonberries and supercritical CO2-extracted herbal extracts from an antimicrobial blend and oregano leaves on the shelf life of broiler meat. The commercial antimicrobial blend extract and the oregano extract inhibited the growth of lactic acid bacteria (LAB) and Brochothrix thermosphacta in the marinated samples. The antimicrobial blend extract also reduced the growth of psychrotrophic aerobic bacteria, whereas the sea buckthorn and lingonberry extracts did not. Only minor antimicrobial activity against Enterobacteriaceae by all the extracts was observed. Plate count analysis, denaturing gradient gel electrophoresis, and quantitative real-time PCR indicated that LAB, which are the major spoilage group in marinated modified atmosphere–packaged poultry products, were not significantly affected by the berry extracts studied. During this shelf-life study, LAB isolates of Lactobacillus and Leuconostoc were identified in the marinated samples. Antimicrobial blends and oregano leaf extracts can act as antimicrobial agents in marinade blends, although tailoring of the dose is needed because of their strong taste. Further studies for exploiting synergistic effects of plant extracts could contribute to the development of potential and more effective antimicrobial blends. Studies are needed in meat matrices and in product applications to demonstrate the efficacy of these compounds.

Optimized nutrition during the first 1000 days (from conception through the 2nd birthday) is critical for healthy development and a healthy life for the newborn. Pregnancy and the postpartum period are accompanied by physiological changes, increased energy needs, and changing requirements in the nutrients critical for optimal growth and development. Infants and toddlers also experience physiological changes and have specific nutritional needs. Food and nutrition experts can provide women of childbearing age with adequate dietary advice to optimize nutrition, as well as guidance on selecting appropriate dietary supplements. Considering the approaching 2020–2025 Dietary Guidelines for Americans (DGA) will be making specific recommendations for children, it is important to provide accurate scientific information to support health influencers in the field of nutrition. The purpose of this review is to summarize the nutrition and supplementation literature for the first 1000 days; to highlight nutritional and knowledge gaps; and to educate nutrition influencers to provide thoughtful guidance to mothers and families. Optimal nutrition during pregnancy through early childhood is critical for supporting a healthy life. Nutrition influencers, such as dietitians, obstetricians/gynecologists, and other relevant health professionals, should continue guiding supplement and food intake and work closely with expectant families and nutrition gatekeepers.

OBJECTIVES: Human breast milk contains a high quantity of oligosaccharides (HMOs) which are not digested by infants but are selectively utilized by beneficial gut microbes such as Bifidobacterium species. The gut microbiome in breast-fed infants is dominated by Bifidobacterium species, whereas formula-fed infants have a higher representation of Bacteroides and Enterobacteria species. The aim of this study was to evaluate the ability of various potentially pathogenic bacteria and commercially available probiotic strains to grow using the HMOs 2’-fucosyllactose (2’-FL) and 3-fucosyllactose (3-FL), glucose, lactose or galacto-oligosaccharide (GOS) as a sole carbon source. We also compared the production of short-chain fatty acids (SCFAs) and lactic acid during the fermentation of 2’-FL by B. infantis, B. bifidum and Bacteroides strains. METHODS: Bacterial growth was monitored by measuring the absorbance at 600 nm every 30 min for 24 h using the automatic Bioscreen(©) C system under anaerobic conditions in culture media containing 1% 2’-FL, 3-FL, glucose, lactose or GOS as a sole carbon source. Metabolites were analyzed by chromatographic methods in spent culture media after over-night growth of bacterial strains with 1% 2’-FL. RESULTS: Only certain bifidobacteria strains, B. infantis and B. bifidum, were able to utilize 2’-FL and 3-FL, whereas other tested Lactobacillus and Bifidobacterium strains as well as pathogenic bacteria grew with all other carbon sources. We also confirmed that Bacteroides fragilis, B. thetaiotaomicron and B. vulgatus strains utilized HMO. Distinct SCFA and lactic acid quantities were observed between Bifidobacterium and Bacteroides strains in 2’-FL fermentation. For instance, acetic and lactic acids were produced at much higher levels in Bifidobacterium than in Bacteroides, and propionic acid was produced at low level only in Bacteroides. CONCLUSIONS: These results show the selectivity of 2’-FL and 3-FL utilization in certain Bifidobacterium and Bacteroides strains, which is translated to differences in metabolite production between these individual HMO-utilizing bacteria. Further studies will enlighten the role and potential benefits of HMOs as a selective substrate for gut microbes, as well as for competition and cross-feeding of microbial metabolites among gut species. FUNDING SOURCES: This research was funded by DuPont Nutrition and Health.

Study how the dietary intake affects the fecal microbiota of a group of obese individuals after a 6-week very low-energy diet (VLED) and thereafter during a follow-up period of 5, 8, and 12 months. Additionally, we compared two different methods, fluorescent in situ hybridization (FISH) and real-time PCR (qPCR), for the quantification of fecal samples. Sixteen subjects participated in a 12-month dietary intervention which consisted of a VLED high in protein and low in carbohydrates followed by a personalized diet plan, combined with exercise and lifestyle counseling. Fecal samples were analyzed using qPCR, FISH, and denaturing gradient gel electrophoresis. The VLED affected the fecal microbiota, in particular bifidobacteria that decreased approximately two logs compared with the baseline numbers. The change in numbers of the bacterial groups studied followed the dietary intake and not the weight variations during the 12-month intervention. Methanogens were detected in 56 % of the participants at every sampling point, regardless of the dietary intake. Moreover, although absolute numbers of comparable bacterial groups were similar between FISH and qPCR measurements, relative proportions were higher according to FISH results. Changes in the fecal microbial numbers of obese individuals were primarily affected by the dietary intake rather than weight changes.

Lignin is a constituent of plant cell walls and thus is classified as part of dietary fiber. However, little is known about the role of lignin in gastrointestinal fermentation. In this work, a lignin-rich fraction was prepared from brewer’s spent grain and subjected to an in vitro colon model to study its potential bioconversions and interactions with fecal microbiota. No suppression of microbial conversion by the fraction was observed in the colon model, as measured as short-chain fatty acid production. Furthermore, no inhibition on the growth was observed when the fraction was incubated with strains of lactobacilli and bifidobacteria. In fact, the lignin-rich fraction enabled bifidobacteria to survive longer than with glucose. Several transiently appearing phenolic compounds, very likely originating from lignin, were observed during the fermentation. This would indicate that the gut microbiota was able to partially degrade lignin and metabolize the released compounds.

Recently several human health-related microbiota studies have had partly contradictory results. As some differences may be explained by methodologies applied, we evaluated how different storage conditions and commonly used DNA-extraction kits affect bacterial composition, diversity, and numbers of human fecal microbiota. According to our results, the DNA-extraction did not affect the diversity, composition, or quantity of Bacteroides spp., whereas after a week's storage at −20 °C, the numbers of Bacteroides spp. were 1.6–2.5 log units lower (P < 0.05). Furthermore, the numbers of predominant bacteria, Eubacterium rectale (Erec)-group, Clostridium leptum group, bifidobacteria, and Atopobium group were 0.5–4 log units higher (P < 0.05) after mechanical DNA-extraction as detected with qPCR, regardless of storage. Furthermore, the bacterial composition of Erec-group differed significantly after different DNA-extractions; after enzymatic DNA-extraction, the most prevalent genera detected were Roseburia (39% of clones) and Coprococcus (10%), whereas after mechanical DNA-extraction, the most prevalent genera were Blautia (30%), Coprococcus (13%), and Dorea (10%). According to our results, rigorous mechanical lysis enables detection of higher bacterial numbers and diversity from human fecal samples. As it was shown that the results of clostridial and actinobacterial populations are highly dependent on the DNA-extraction methods applied, the use of different DNA-extraction protocols may explain the contradictory results previously obtained.

The aim of the study was to evaluate the potential of utilising the information on expression levels of selected stress genes in assessing the quality of probiotic products. For this purpose RT-qPCR methods were developed to study the expression of clpL1 and clpL2 stress genes in Lactobacillus rhamnosus VTT E-97800 (E800) cells after exposure to processing-related stress conditions or to freeze-drying. Heat treatments in laboratory scale were performed with E800 cells incubated at 47 °C or 50 °C for 60 min. Acid treatments were performed both at laboratory and fermenter scale. At laboratory scale E800 cells were inoculated into General Edible Medium (GEM) adjusted to pH 4.0 and pH 3.5 and incubated at 37 °C for 180 min, whereas fermenter-grown cells were exposed to pH 4.0 for 60 min at the end of the fermentation. RNA from fresh cells and freeze-dried powders was reverse transcribed after isolation, quantification and standardisation. clpL1 and clpL2 transcripts were analysed by RT-qPCR with SYBR Green I. clpL1 was induced in L. rhamnosus E800 cells exposed to 50 °C and to a much lesser extent to 47 °C. No induction was observed for clpL2 in E800 cells during either acid or heat treatment, in any of the conditions applied. RNA isolation from freeze-dried powders was unsuccessful although several attempts were made with high quality products. In conclusion, our results suggest that developing quality indicators for probiotic products based on differences in the expression of stress genes is a challenging task for several reasons: at least with some genes (like in the present study with clpL) quite harsh conditions are needed to detect differences in the gene expression; mRNA isolation from freeze-dried powders was unsuccessful which hampers the quality analysis of large proportion of probiotic products; and furthermore RT-qPCR proved to be a too laborious procedure for routine use.

There is a wealth of techniques that can and have been used for the characterization of industrial microbial communities. Recently, especially PCR-based methods have been starting to replace culture-based approaches, and in microbial community analysis, for example, high-throughput methods such as denaturing high-performance liquid chromatography (DHPLC) have been utilized for analysis of industrial samples. In this manuscript we will review the advances achieved in the identification and quantification of industrial microbial communities in addition to progress in the study of microbial diversity and function of the industrial microbial communities.

In the present study, polyphasic analysis [cultivation, combined with the fingerprinting of individual isolates, and denaturing gradient gel electrophoresis (DGGE)] was applied to study whether similar features concerning the diversity and temporal stability of selected bacterial groups could be detected intra-individually in two different niches – the oral cavity and the colon – from ten adult volunteers consuming probiotics. The predominant bacterial microbiota, Clostridium coccoides–Eubacterium rectale group and bifidobacterial populations, were generally stable in salivary and faecal samples, with the greater diversity seen in faeces. Furthermore, different species predominated at the two different sites. Lactobacillus group DGGE profiles were unstable, yet the intra-individual profiles from faecal and salivary samples collected at the same time resembled each other. The ingested probiotic product did not affect the stability of the bacterial groups studied. The culture-based analysis showed that most subjects harboured identical indigenous Lactobacillus genotypes in saliva and faeces (Lactobacillus rhamnosus, Lactobacillus gasseri, Lactobacillus paracasei and Lactobacillus plantarum group). Thus, identical indigenous lactobacilli were able to inhabit both ends of the orogastrointestinal tract, whereas the composition of the other bacterial groups studied varied between the two sites.

Denaturing gradient gel electrophoresis was applied to study the effect of 3-week consumption of probiotic yoghurt containing galacto-oligosaccharides (GOS) on intra-individual diversity and temporal stability of predominant bacterial, bifidobacterial, Lactobacillus-group, and Erec-group Eubacterium rectale–Clostridium coccoides fecal populations of elderly subjects. Diversity and temporal stability of the selected bacterial groups of elderly subjects were compared with those obtained from younger adults in our previous studies. In the present study, GOS-yoghurt consumption did not significantly affect diversity or temporal stability of the selected bacterial groups. On average, the Erec-group and the predominant bacterial and bifidobacterial populations remained almost stable, and the Lactobacillus-group was unstable in elderly subjects. No differences were found between elderly and younger adults in temporal stability of studied bacterial populations. However, the difference in diversity of predominant bacterial population and Erec-group bacteria was significantly higher in elderly subjects of this study as compared with younger adults from our previous studies.

Article, We showed previously that ellagitannin-rich cloudberries and anthocyanin-rich bilberries reduce the number of intestinal adenomas in multiple intestinal neoplasia/+ (ApcMin) mice. We also found that cloudberries decreased the size of adenomas, whereas bilberries increased it. Here we hypothesized that the difference in adenoma growth could be explained by dissimilar effects of the berries on intestinal immune responses and gut microbiota, potentially driven by the distinct polyphenol compositions of the 2 berries. Our objectives were to investigate lymphocyte subtypes and the predominant cecal bacterial diversity in mice fed with bilberries and cloudberries, and to analyze global gene expression profiles in the intestinal mucosa. Immunostainings of CD3+ T lymphocytes, FoxP3+ regulatory T lymphocytes, and CD45R+ B lymphocytes revealed a smaller ratio of intraepithelial to all mucosal CD3+ T lymphocytes in the cloudberry-fed mice compared with controls, suggesting an attenuation of inflammation. Bilberry feeding induced no changes in the density of any of the lymphocyte subtypes. The predominant bacterial diversity in cecal contents, analyzed using polymerase chain reaction–denaturating gradient gel electrophoresis, was higher in the bilberry group than in the control or cloudberry groups. The microbial profiles of cloudberry-fed mice clustered together and were associated with small adenoma size. Pathway analyses of gene expression data showed that cloudberry down-regulated and bilberry up-regulated the expression of energy metabolism–related genes in the intestinal mucosa. In conclusion, attenuation of intestinal inflammation, changes in microbial profiles, and down-regulation of mucosal energy metabolism may account for the smaller adenoma size in cloudberry-fed mice in comparison to bilberry-fed mice., final draft, http://purl.org/eprint/status/PeerReviewed

Due to the presence of moisture and nutrients, brewery filling line surfaces are susceptible to unwanted microbial attachment. Knowledge of the attaching microbes will aid in designing hygienic control of the process. In this study the bacterial diversity present on brewery filling line surfaces was revealed by next generation sequencing. The two filling lines studied maintained their characteristic bacterial community throughout three sampling times (13-163 days). On the glass bottle line, γ-proteobacteria dominated (35-82% of all OTUs), whereas on the canning line α-, β- and γ-proteobacteria and actinobacteria were most common. The most frequently detected genera were Acinetobacter, Propinobacterium and Pseudomonas. The halophilic genus Halomonas was commonly detected, which might be due to its tolerance to alkaline foam cleaners. This study has revealed a detailed overall picture of the bacterial groups present on filling line surfaces. Further effort should be given to determine the efficacy of washing procedures on different bacterial groups.

We investigated the effects of oral therapy with doxycycline, a tetracycline group antibiotic, on the gastrointestinal (GI) survival and tetracycline susceptibility of probiotic strains Lactobacillus acidophilus LaCH-5 and Bifidobacterium animalis subsp. lactis Bb-12. In addition, the influence of doxycycline therapy on the diversity of the predominant faecal microbiota was evaluated by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Faecal samples from the antibiotic group (receiving antibiotics and probiotics) and the control group (receiving probiotics only) were analysed for anaerobically and aerobically growing bacteria, bifidobacteria and lactic acid bacteria as well as for the dominant microbiota. Although doxycycline consumption did not have a large impact on GI survival of the probiotics, it had a detrimental effect on the bifidobacteria and on the diversity of the dominant faecal microbiota. A higher proportion of tetracycline-resistant anaerobically growing bacteria and bifidobacteria was detected in the antibiotic group than in the control group. Several antibiotic group subjects had faecal B. animalis subsp. lactis Bb-12-like isolates with reduced tetracycline susceptibility. This was unlikely to be due to the acquisition of novel tetracycline resistance determinants, since only tet(W), which is also present in the ingested B. animalis subsp. lactis Bb-12, was found in the resistant isolates. Thus, concomitant ingestion of probiotic L. acidophilus LaCH-5 and B. animalis subsp. lactis Bb-12 with the antibiotic did not generate a safety risk regarding the possible GI transfer of tetracycline resistance genes to the ingested strains.

As the Clostridium coccoides-Eubacterium rectale (Erec; clostridial phylogenetic cluster XIVa) group is one of the major groups of the human intestinal microbiota, DNA- and RNA-based population analysis techniques (denaturing gradient gel electrophoresis; DGGE) were developed and applied to assess the diversity and temporal stability (6 months-2 years) of this faecal clostridial microbiota in 12 healthy adults. The stability of the Erec group was compared with the stability of the predominant bacterial microbiota, which was also assessed with PCR-DGGE. In addition, the Erec group was quantified with a hybridization-based method. According to our results, the Erec group was diverse in each subject, but interindividual uniqueness was not as clear as that of the predominant bacteria. The Erec group was found to be temporally as stable as the predominant bacteria. Over 200 clones obtained from two samples proved the developed method to be specific. However, the amount of bacteria belonging to the Erec group was not related to the diversity of that same bacterial group. In conclusion, the newly developed DGGE method proved to be a valuable and specific tool for the direct assessment of the stability of the Erec group, demonstrating diversity in addition to short-term stability in most of the subjects studied.

Background and Aims: Several factors support the view of inflammatory bowel disease [IBD] origin in the host responsiveness to intestinal bacteria, although no single bacterial species has been shown as a causative agent in the pathogenesis. Our aim was to analyse the fecal microbiota of paediatric IBD patients at different stages of the disease. In addition, the characteristics of immune response to the bacterial isolates showing very low abundance in IBD were studied. Methods: Fecal samples [1–3 samples/child] were collected from 10 paediatric patients with crohn’s disease [CD],] and 12 with ulcerative colitis [UC] and from 8 healthy children, for polyphasic microbiological analysis (culture, real-time polymerase chain reaction [PCR], and denaturing gradient gel electrophoresis). In addition , in vitro cytokine responses of peripheral blood mononuclear cells to the bacterial isolates, which showed very low abundance in IBD, were studied. Results: Although predominant bacterial diversity was higher in IBD, the numbers of Lachnospiraceae and Coriobacteriaceae bacteria were lower in IBD patients as compared with control children [ p < 0.05]. In addition, Ruminococcaceae population diversity was lower in IBD [ p < 0.05] and correlated negatively with fecal calprotectin levels. Both abundance and diversity of bifidobacterial populations were lower in children with IBD [ p < 0.05], and particularly low numbers of certain bifidobacterial isolates were detected. In CD, we found enhanced up-regulation of interleukin-6 transcripts and impaired RAR-related orphan receptor C response to bifidobacteria, whereas decreased interferon-gamma response was observed in both CD and UC. Conclusion: We demonstrate altered fecal microbiota in paediatric IBD, particularly low numbers and diversity of bifidobacterial populations. Interestingly, immunological response to bifidobacteria differed between paediatric CD patients and control children.

In vitro colon model was first applied in an inter-laboratory dietary fibre (DF) fermentation study and adapted at VTT for whole foods and beverages, isolated dietary phenolic compounds and pharmaceuticals. The application of the models includes strict anaerobiosis, which ensures active anaerobic microbial community. Pooling of faecal samples from several donors ensures reproducibility between the experiments. The correlation of in vitro data with in vivo data is quantitatively challenging, but is qualitatively highly relevant. In this chapter we explain the applicability of the one compartment fermentation model, including the general protocol as well as the advantages and disadvantages of the system.

In the present study various combinations of metabolic indicators were used in viability studies of foodborne spoilage and pathogenic organisms. Various metabolic stains were tested in pure culture suspensions of Pseudomonas fragi and Listeria monocytogenes containing only viable cells, both viable and dead cells or only dead cells. In addition, foodborne monospecies biofilms of L. monocytogenes and P. fragi were studied. The biofilms were grown on stainless steel (AISI 304, 2B) surfaces. The results showed that both the LIVE/DEAD Bac Light Viability Kit (LIVE/DEAD) and the 5-cyano-2,3-ditolyl tetrazolium chloride (CTC)-4′,6-diamidino-2-phenylindole (DAPI) staining procedures offer a rapid, easy and reliable method for metabolic investigation of bacteria in suspension and swabbed biofilm bacteria. Assessment of replicate samples using luciferin–luciferase-based ATP measurement and conventional cultivation corroborated the results of swabbed biofilm bacteria obtained by staining. LIVE/DEAD staining cannot be used for direct staining of biofilms on surfaces, due to interference between the stain and polysaccharides of the biofilm matrix and slime. Staining by CTC-DAPI is suitable for studying viability of cells both in suspension and in biofilms attached to surfaces. The other staining procedures tested were not satisfactory or only slightly satisfactory in distinguishing between viable and dead cells.

Postprandial responses to food are complex, involving both genetic and environmental factors. We studied postprandial responses to a Big Mac meal challenge in monozygotic co-twins highly discordant for body weight. This unique design allows assessment of the contribution of obesity, independent of genetic liability. Comprehensive metabolic profiling using 3 analytical platforms was applied to fasting and postprandial serum samples from 16 healthy monozygotic twin pairs discordant for weight (body mass index difference >3 kg/m2). Nine concordant monozygotic pairs were examined as control pairs. Fecal samples were analyzed to assess diversity of the major bacterial groups by using 5 different validated bacterial group specific denaturing gradient gel electrophoresis methods. No differences in fecal bacterial diversity were detected when comparing co-twins discordant for weight (ANOVA, P

Ellagitannins are polyphenols abundant in strawberries, raspberries, and cloudberries. The effects of a mixture of these berries were studied in a randomized controlled trial with subjects having symptoms of metabolic syndrome. The study focused on serum lipid profiles, gut microbiota, and ellagitannin metabolites. The results indicate that bioavailability of ellagitannins appears to be dependent on the composition of gut microbiota.

The impact of diet on the gut microbiota has usually been assessed by subjecting people to the same controlled diet and thereafter following the shifts in the microbiota. In the present study, we used habitual dietary intake, clinical data, quantitative polymerase chain reaction, and denaturing gradient gel electrophoresis (DGGE) to characterize the stool microbiota of Finnish monozygotic twins. The effect of diet on the numbers of bacteria was described through a hierarchical linear mixed model that included the twin individuals, stratified by body mass index, and their families as random effects. The abundance and diversity of the bacterial groups studied did not differ between normal-weight, overweight, and obese individuals with the techniques used. Intakes of energy, monounsaturated fatty acids, n3 polyunsaturated fatty acids (PUFAs), n6 PUFAs, and soluble fiber had significant associations with the stool bacterial numbers (e.g., increased energy intake was associated with reduced numbers of Bacteroides spp.). In addition, co-twins with identical energy intake had more similar numbers and DGGE-profile diversities of Bacteroides spp. than did the co-twins with different intake. Moreover, the co-twins who ingested the same amounts of saturated fatty acids had very similar DGGE profiles of Bacteroides spp., whereas the co-twins with similar consumption of fiber had a very low bifidobacterial DGGE-profile similarity. In conclusion, our findings confirm that the diet plays an important role in the modulation of the stool microbiota, in particular Bacteroides spp. and bifidobacteria.

Aim: To evaluate the influence of doxycycline therapy on the composition and antibiotic susceptibility of intestinal bifidobacteria. Methods and Results: Faecal samples were collected from nine subjects receiving doxycycline therapy and ten control subjects, and analysed for bifidobacteria by culturing and PCR–DGGE (denaturing gradient gel electrophoresis). A marked decrease in the diversity (average number of amplicons detected by PCR–DGGE 0·8 in the antibiotic vs 4·3 in the control group) of Bifidobacterium populations was observed during doxycycline therapy. The proportion of a tetracycline‐resistant bifidobacterial population was higher in the antibiotic group than in the control group (83%vs 26%). Based on the tet gene PCR, resistance could be associated with the presence of tet(W). In two subjects, strains representing highly similar genetic fingerprints but different tetracycline susceptibilities were detected. A mutation causing lack of functionality in the tet(W) was observed in one of the susceptible strains. Conclusions: Doxycycline therapy had a drastic effect on the diversity and tetracycline susceptibility of intestinal Bifidobacterium populations. Significance and Impact of the Study: The use of broad‐spectrum antibiotics increased the pool of tetracycline‐resistant commensal bacteria in the intestine. The detection of resistance genes alone is not sufficient for the evaluation of bacterial antibiotic resistance.

As the Clostridium coccoides-Eubacterium rectale (Erec; clostridial phylogenetic cluster XIVa) group is one of the major groups of the human intestinal microbiota, DNA- and RNA-based population analysis techniques (denaturing gradient gel electrophoresis; DGGE) were developed and applied to assess the diversity and temporal stability (6 months-2 years) of this faecal clostridial microbiota in 12 healthy adults. The stability of the Erec group was compared with the stability of the predominant bacterial microbiota, which was also assessed with PCR-DGGE. In addition, the Erec group was quantified with a hybridization-based method. According to our results, the Erec group was diverse in each subject, but interindividual uniqueness was not as clear as that of the predominant bacteria. The Erec group was found to be temporally as stable as the predominant bacteria. Over 200 clones obtained from two samples proved the developed method to be specific. However, the amount of bacteria belonging to the Erec group was not related to the diversity of that same bacterial group. In conclusion, the newly developed DGGE method proved to be a valuable and specific tool for the direct assessment of the stability of the Erec group, demonstrating diversity in addition to short-term stability in most of the subjects studied.

The suitability of the fluorescent techniques for the microbiological quality assessment of probiotic non-dairy drinks and probiotic pharmaceutical products was studied. The method optimization was first performed with pure cultures of probiotic strains detected in commercial products (representing Lactobacillus and Bifidobacterium species). Altogether seven different fluorescent viability stains combined with epifluorescence microscopy and flow cytometry were tested. The most applicable stains ChemChrome and LIVE/DEAD BacLight Viability Kit were further used for the viability studies of the commercial probiotic products. The studied products proved to be of good quality. All products contained the probiotic bacterium indicated on the label and the levels of living bacteria were reasonable per dose (108–1010 cells for suggested daily dose of pharmaceutical products and 108–109 cells per 100 ml of drink). The results obtained with fluorescent stains were mostly in agreement with results obtained with culture, rendering fluorescent techniques applicable alternatives for rapid viability assessment of probiotic products. Especially the newly developed fluorometry assay with BacLight proved to be fast and accurate.

The aim of this study was to find out whether liquorice-containing starch gel could affect plaque accumulation and its microbial composition. Sixteen healthy volunteers (mean age: 30.4+/-6.9 years) used 6 g of either control [8% acid-hydrolyzed corn starch, 25% maltitol syrup, water (w/w)] or liquorice gel (control + 2.5% liquorice extract), three times a day for 2 weeks. The gels were used in a random order with a 2-week washout period in between. At the end of each fortnight, plaque was allowed to accumulate for 2 days and all available plaque from the right side of the mouth was collected, weighed, and transferred to transport medium. The plaque on the left side was dyed and photographed in a standardized manner. Mutans streptococci, total streptococci, and facultative bacteria were assessed from the plaque using plate culturing. Plaque index (0-5) of incisors and canines on the left side was evaluated from the photographs. The clinical study was preceded by an in vivo acid production test. The acid production from gels containing 2.5-10% liquorice extract was monitored with a microelectrode. The in vivo acid production potential of the maltitol-containing starch gel was about 50% compared to the sucrose control. Liquorice inhibited acid production from the gel. In the clinical study, the weight of plaque after consumption of the liquorice gel did not differ from that of the control gel. No differences were found in the microbial counts nor in the plaque index between the two gels. In addition, the liquorice gel had no effect on the stability of the predominant bacterial populations of the plaque samples of 16 individuals as detected by PCR-denaturing gradient gel electrophoresis. In conclusion, an addition of liquorice extract to starch-containing gel with a low acid production potential had no effect on the plaque formed during a 2-week gel consumption period.

The aim of the present study was to evaluate the suitability of a nested PCR-DGGE (denaturing gradient gel electrophoresis) method for the detection of Desulfovibrionales-related sulfate-reducing bacteria (SRB) from paper mill samples. The samples were also analyzed with culturing. SRB cause/enhance industrial problems, namely creation of foul-smelling gases (hydrogen sulfide) and biological corrosion, and so far there has not been a simple method to study these bacteria in paper mill laboratories. In our study, culturing was able to detect Desulfovibrionales-related bacteria from two different white waters, two different brokes, pulp, clay, and slime. Out of the isolated Desulfovibrionales, 23 enrichment cultures were further characterized with Desulfovibrionales-selective PCR-DGGE. An identical Desulfovibrio species sequence was found from paper machine I (broke I, slime, and pulp) and from paper machine II (broke II and white water II), suggesting an in-house contamination with the same strain. Desulfovibrionales-selective PCR-DGGE was also performed from DNA templates extracted directly from the paper mill samples. The DGGE profiles derived from the samples without prior enrichment were more diverse and the sequenced amplicons proved to belong to the Desulfovibrionales order. Moreover, molecular techniques were able to detect Desulfovibrionales-related bacteria from calcium carbonate samples whereas culture did not. Altogether, the nested PCR-DGGE method used in this study was suitable for the detection of Desulfovibrionales-related SRB directly from different paper mill samples and it could be used for the rapid identification of SRB-contaminated industrial sites and, when combined with sequencing, for tracing of the contamination routes.

The differences in faecal bacterial population between irritable bowel syndrome (IBS) and control subjects have been reported in several studies. The aim of the present study was to compare the predominant and clostridial faecal microbiota of IBS subjects and healthy controls by applying denaturing gradient gel electrophoresis (DGGE) and a recently developed multiplexed and quantitative hybridization-based technique, transcript analysis with the aid of affinity capture (TRAC). According to the results, the studied clostridial groups (Clostridium histolyticum, Clostridium coccoides-Eubacterium rectale, Clostridium lituseburense and Clostridium leptum) represented the dominant faecal microbiota of most of the studied subjects, comprising altogether 29–87 % of the total bacteria as determined by the hybridized 16S rRNA. The C. coccoides-E. rectale group was the dominant subgroup of clostridia, contributing a mean of 43 % of the total bacteria in control subjects and 30 % (constipation type) to 50 % (diarrhoea type) in different IBS symptom category subjects. The proportion of the C. coccoides-E. rectale group was found to be significantly lower in the constipation-type IBS subjects than in the control subjects. DNA-based PCR-DGGE and RNA-based RT-PCR-DGGE analyses targeted to the predominant bacterial population showed considerable biodiversity as well as uniqueness of the microbiota in each subject, in both control and IBS subject groups. The RT-PCR-DGGE profiles of the IBS subjects further indicated higher instability of the bacterial population compared to the control subjects. The observations suggest that clostridial microbiota, in addition to the instability of the active predominant faecal bacterial population, may be involved in IBS.

In the gut, the interaction between the tumor tissue and its microenvironment including the microbiota and immune cells may play a significant role in the carcinogenic process. Here we studied whether the anti-carcinogenic effects of berry diets were mediated by changes in the gut microbiota and immune cells. Male and female Min mice were fed modified high-fat AIN93-G diets containing 10% (w/w) freeze-dried bilberry or cloudberry for 10 weeks. The control diet was similar but without any berries. Mucosal B and T lymphocytes were analysed using immunohistochemical staining. The microbial profile was determined carrying out PCR-DGGE analysis using bacterial genomic DNA extracted from caecal contents. Microbial PCR-DGGE profiles contained 10-19 amplicons, indicating that the microbiota in the mouse cecum contents is diverse. According to their PCR-DGGE patterns, samples of control and cloudberry-fed mice could be divided to well-defined subgroups both visually and using Molecular Analyst software. Instead, visual grouping of the samples of bilberry-fed mice was impossible and the samples were only grouped using the software. In the control mice, amplicons a-d were present in all samples but on the basis of their intensity, amplicons b-d represented the dominant species. In the cloudberry mice, amplicons a, c, d, e and f existed in all samples but some of them lacked a pronounced amplicon b. In the bilberry mice, the amplicons a-e existed in all samples. In addition, bilberry samples contained amplicon g that seemed to be more prevalent and intense than in the samples of the other two groups. The amplicon g was sequenced and found to belong to the Clostridiales order of the Clostridia class in the Firmicutes phylum and to represent an uncultured bacterium clone abc21b07.x1: AY667976. Cloudberry feeding resulted in a smaller density of mucosal CD3+ T lymphocytes (p=0.149) and a significantly smaller ratio of intraepithelial to total CD3+ T lymphocytes (p=0.034) when compared to the control group. Furthermore, there was a significant positive correlation (p=0.012) between the ratio of intraepithelial to total CD3+ T lymphocytes and adenoma burden in the small intestine of Min mice. Interestingly, no difference in the density of any lymphocytes was found between the bilberry and the control group. Berry feeding did not affect the density of B lymphocytes in the intestinal mucosa. Here we show that berry feeding changes the microbiota and the distribution of immune cells in the intestine of Min mice and these changes are associated with adenoma formation. Citation Format: Anne-Maria Pajari, Essi Paivarinta, Johanna Maukonen, Mikael Niku, Anu Heiman-Lindh, Maria Saarela, Marja Mutanen. Berry feeding changes gut microbiota and immune function in association with adenoma formation in the Min mouse. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4871. doi:10.1158/1538-7445.AM2013-4871

Scope: Ellagitannins are polyphenols abundant in strawberries, raspberries and cloudberries. The effects of a mixture of these berries were studied in subjects with features of metabolic syndrome. The study focused on cardiovascular risk factors, gut microbiota and ellagitannin metabolites. Methods and Results: Twenty subjects consumed 300 g of ellagitannin rich berries daily for 8 weeks ina randomized controlled trial. A control group, with twelve subjects, ate no berries. Most measured variables did not differ between the two study groups. However, minor positive alterations were observed in systolic blood pressure, LDL cholesterol, 8-isoprostane, TRAP and resistin. Statistical modelling of lipidprofiles pinpointed a group of 20 lipids for sample separation, indicating that they may be responsible for known positive health effects of berries. Berry supplementation caused changes to microbiota in 35% of the subjects. All these changes were related to either Families of Ruminococcaceae or Lachnospiraceae,which are the main butyrate-producing bacteria in the human colon. A majority of the subjects in the berry group were identified as urolithin producers.Conclusions: Ellagitannin rich berry supplementation may have positive effects on serum lipid profiles and on gut microbiota, which might modify bioavailability of the berry ellagitannins. Future studies in humans are warranted.