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ScienceDirect Editorial overview: Food biotechnology: Microbial ecosystem management: strategies to adapt ecosystems to improve performance and health impact Michiel Kleerebezem and Christophe Lacroix Current Opinion in Biotechnology 2015, 32:v–viii For a complete overview see the Issue Available online 27th February 2015 http://dx.doi.org/10.1016/j.copbio.2015.02.009 0958-1669/# 2015 Elsevier Ltd. All rights reserved.
Michiel Kleerebezem
Host Microbe Interactomics Group, Department of Animal Sciences, Wageningen University, The Netherlands e-mail: [email protected] Michiel Kleerebezem is professor of Host Microbe Interactions, at the Department of Animal Sciences of Wageningen University as well as Principal Scientist at the Health Department of NIZO food research. His research expertise centers around the molecular biology and physiology of bacteria, with a special focus on lactic acid bacteria, probiotics, and the intestinal microbiota. In recent years he has expanded his field to the (post-genomic) molecular analysis of the mechanisms of communication between intestinal bacteria and the host mucosa. His work aims to understand and improve the functional performance of starter cultures for industrial fermentation and probiotic application, while his work on the intestinal microbiota and probiotics strives to decipher the molecular cross-talk between these intestinal microbes and the host’s mucosa in order to enhance their application potential for the benefit of human and animal health.
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Microbes and their ecosystems are intimately connected to our life, environment, food and health. Microbes of our body, particularly the gut microbiota, provide many essential functions related to development, immunity, digestion, nutrition and pathogen protection. Probably the biggest challenge facing humanity is our capacity to feed the world, with an expanding and ageing population. Moreover, the United Nations World Food Program, estimated that more than 870 million people are malnourished. Many of these people are children, leading to approximately one out of six children being underweight, and knowing that malnutrition contributes to the death of 2.6 million children each year. At the same time, approximately one-third of all available food products is wasted. Feeding a global population that is projected to reach 9 billion by 2050 will require an increase of agricultural yields by 70–100%, but also demands major food innovations aimed to nourish Man’s health, by preventing and treating the expanding chronic diseases. In view of these requirements it is crucial to improve our understanding of the roles fulfilled by microbes and ecosystems in the environment and food production processes, but also those associated with our own body. Such understanding is crucial to harness the tremendous potential of microbes in food processing, nutrition and health. Over the past years, considerable advances have been made in characterizing composition and roles of microbes in food and in the human gut. Tremendous advances in life sciences supported by next generation sequencing (NGS) that fuels (meta-)genomics, as well as high-resolution metabolomics are revolutionizing our understanding of microbes and ecosystems associated with nutrition and health. These advances have led to groundbreaking discoveries in novel functions of microbes in food and humans. This includes functions related to production of safe, sustainable and healthy fermented foods as well as health-promoting microbes and other food ingredients. The intestinal microbiota research is starting to decipher how food and food ingredients may support pathogen protection, restoration of gut microbiota balance and diversity, and nutrient digestion and conversion, which in the long run could contribute to the prevention or correction of a broad range of chronic diseases, including those related to inflammation and immunity (IBD, IBS, [food-] allergy, autoimmunity, etc.), metabolism (obesity, diabetes, etc.), and/or even neurology (Parkinson, autism, etc.). However, causality, underlying mechanism, and nutritional strategies for microbiota modulation are still to be demonstrated. The high biodiversity of the intestine provides a unique source of microbial capacities, encompassing known and many still to be discovered functions. Molecular methods have tremendously contributed to our understanding of the genetic and metabolic Current Opinion in Biotechnology 2015, 32:v–viii
vi Food biotechnology
Christophe Lacroix
Laboratory of Food Biotechnology, Institute of Food Science and Nutrition, ETH Zurich, Switzerland e-mail: [email protected] Christophe Lacroix is Professor for Food Biotechnology, Department of Health Science and Technology, at the Swiss Federal Institute of Technology Zurich. His main research interests include the fundamental and technological characterization of functional microbes and their roles in food and intestinal ecosystems, with multidisciplinary system-oriented aspects. This includes ecosystem study and microbe screening and characterization, functional studies and mechanisms, microbial technology, and intestinal research (from in vitro modeling to in vivo human studies). In his teaching, he aims to bridge basic knowledge of natural sciences and engineering sciences in order to achieve the application of microorganisms, enzymes and metabolites for processing of high quality, safe and healthy food and functional ingredients.
potential of the intestinal ecosystem. However, harnessing the potential of microbiota for the improvement of health, still requires their cultivation and functional characterization. This is a challenging task for strict anaerobes, and using cultivation techniques that were mainly developed in the sixties, which may recover less than 30% of the overall intestinal microbes. This challenge certainly extends to efficient large scale production and processing of gut microbes for health-promoting supplement applications, but also impacts our capacity to rationally design dietary ingredients aiming to stimulate health-supporting microbiota, or even correcting the unbalanced microbiota correlated with disease. Imposing selective environmental pressures on microorganisms may be exploited to deliberately adapt microbes to environmental niches or industrial processes in which they are applied, selecting for improved industrial performance in food fermentation processes or enhanced functionality within microbial ecosystems. Inversely, environmental challenges can also cause unbalanced, dysbiotic ecosystems with undesirable phenotypes, such as accumulation of resistance genes upon antibiotic treatment, or an inflammation stimulating microbiota in the obese host. The microbial communities adapted to the intestinal ecosystem can be modulated by altering the physicochemical conditions of such habitat by nutritional interventions. Nutritional factors such as fibers, exogenous microbes, and other dietary compounds have not yet been fully investigated for their potential to enhance microbiota fitness, and to prevent or correct non-homeostatic (dysbiotic) host-microbe interactions in human disease. Intestinal microbiota modulations by food hold the potential to influence human health in a variety of domains, including nutritional, metabolic, and immune status with impact on both intestinal — as well as systemic health. In this issue on food biotechnology, the ten excellent contributions address the current status of knowledge of microbial fitness in food production and intestinal microbiota–host interactions, and how this can impact on industrial food-production and ingredient-production, and/or the intestinal microbiota and host health.
From fermented foods, to intestinal microbiota–host interactions, and novel prebiotics and probiotics Our understanding of the molecular changes underlying microbial evolution has been accelerated tremendously by NGS genomics, providing holistic information of the genetic changes that drive the adapted behavior of evolving microbes. Bachmann et al. highlight the revival of experimental evolution strategies for the production of industrial strains with improved fermentation performance and/or enhanced environmental fitness. Recent developments in single cell technologies such as those relying on microfluidics, combined with NGS are fueling the comprehensive character of such approaches and enable improved experimental designs to obtain desired phenotypes. Sustainable performance of microbes in industrial fermentation depends on the effective prevention of phage predation. Mahony and van Sinderen describe the recent advances in the molecular understanding of phage-host recognition and the characterization of the docking molecules involved can open novel avenues for prevention of problems associated with phages in industrial fermentation. Moreover, improved understanding of phage diversity and its mechanisms of interaction with its microbial host may also revive the concept of phage therapy, for example to eradicate food-borne pathogens from products. Current Opinion in Biotechnology 2015, 32:v–viii
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Editorial overview Kleerebezem and Lacroix vii
The development of NGS has revolutionized our understanding of the human intestine microbiota and its relationship with health and disease. The diet is one of the main drivers of gut microbiota establishment and functionality, since it provides the main source of nutrients for the microbes residing in the small intestine and the colon. The (changes in) dietary habits during the first 2–3 years of life importantly shape the gut microbiota of infants, which may have long term, life-span encompassing health impacts. Dore´ and Blottie`re highlight recent developments showing the complex connections of dietary factors, microbiota and host health, and underpinning the importance of microbiota richness as an important homeostasis supporting factor. Understanding mechanisms and effects beyond description could pave the way for rational ingredient design and diet consumption, exemplified by fibers, to prevent or correct loss of symbiosis by stimulation of microbiota resilience and richness. Most research on the intestinal microbiota has targeted the numerically dominant microbes of the human (or animal) large intestine. Much less is known about the small intestine microbiota, although both the physiological function of this part of the intestinal tract as well as a number of recent studies support a prominent role of the small intestine microbiota in modulation of the host’s physiology and health. El Aidy et al. present the most recent advances on the human small intestine microbiota and its effects on immune, metabolic, and endocrine functions. Studying this part of the intestinal tract remains challenging due to its poor accessibility and the relatively high invasiveness of procedures for sampling. However, the modulation of the small intestine microbiota by diet provides a feasible and promising target, which may enable enhancement of both local and systemic immune, endocrine and metabolic processes that beneficially impact on host health. Prebiotics, defined as ‘non-digestible food components that exert specific stimulation of gut bacteria, for beneficial effect on the host’, are among the dietary ingredients targeted to modulate the intestinal microbiota. Rastall and Gibson expand the view on prebiotics beyond the classical prebiotic fructans and galactans that have been well studied for their effect on intestinal bifidobacteria, towards other candidate prebiotics that are investigated. These food ingredients may eventually target a broader range of beneficial gut bacteria and are investigated in an expanding range of health-benefits, including their prophylactic and therapeutic potential in immune-diseases and metabolic-diseases. Prebiotics may derive from biosynthetic processes using enzymatic polymerization of simple sugars or may be generated by controlled hydrolysis of complex polysaccharide-containing materials of plants or agricultural and/or food processing waste streams. To eventually support prebiotic health-claims, it is of critical importance to demonstrate their specificity www.sciencedirect.com
in microbiota modulation and the corresponding health promoting mechanisms. Probiotics classically refer to food-grade microbes that are consumed in alive to confer a health benefit to the consumer. Many of the currently marketed products contain lactobacilli or bifidobacteria, although also probiotics of other genera are available. The expanding association of specific intestinal microbial species with health, and the success of fecal microbiota transplantation in some disease treatments, has fueled the interest in the preparation of specific, or mixtures of intestinal microbial species for their application as next-generation probiotics. Claes et al. evaluate the status of this field and exemplify that adequate knowledge of the mechanism of action of classical and/or next generation probiotics is critical to predict their health potential. Moreover, these authors also underline the importance of stratification of the target population for the prediction of the efficacy of microbial intervention, as well as the need for multivariate analyses to establish its impact on host physiology. The concept of next-generation probiotics is placed in the context of their possible role in therapeutic approaches in metabolic syndrome patients. Cani and van Hul highlight the potential of probiotic therapies in the treatment of obesity and/or associated disorders like diabetes. Several studies report on the beneficial impact of classical probiotic lactobacilli and bifidobacteria and/or other species (including the yeast probiotic Saccharomyces cerevisiae var. boulardii) on physiological parameters of the host associated with metabolic syndrome, including body weight and fat-mass reduction, suppression of hepatic and adipose tissue inflammation, etc. The importance of bile acids as signaling molecules in regulation of the host’s energy, glucose and fatty acid metabolism may provide rational selection strategies for more effective probiotics, for example based on their bile hydrolyzing capacities. Finally, the authors describe the recent findings related to a possible role of the intestinal microbe Akkermansia municiphila in controlling host metabolism and its potential as a next generation probiotic in the treatment of metabolic syndrome. Mechanisms of dietary factors on gut microbiota and gut health are still poorly understood despite continuous expansion of metadata generated by large scale projects all over the world. Lacroix et al. highlight the importance of the rational combination of investigations using suitable in vitro and in vivo models and human trials to provide mechanistic understanding of health-promoting nutrient function. Recent developments in in vitro and in vivo models, but also the limits of individual modeling strategies, are exemplified, arguing in favor of the combination of various models. Overall, multi-scale strategies that include human trials, with optimal selection and design of each step, offer great potential for advancing Current Opinion in Biotechnology 2015, 32:v–viii
viii Food biotechnology
knowledge on the role of intestinal microbiota and the effects of dietary factors in the healthy and diseased host. A more recent and very exciting area of host health for which a role of the intestinal microbiota has been postulated is related to brain function and behavior. The past years neuroscience research has shown the importance of the microbiota in brain development and its influence on stress associated behavior. Luna and Foster highlight recent advances in studies evaluating the impact of diet induced changes in the microbiota on stress-related behavior like anxiety and depression. The authors underline the potential of targeted dietary interventions using probiotics and prebiotics to beneficially influence behavior. Mechanistic understanding in this area is still in its infancy, and the authors propose that especially host metabolomic analysis in relation to intestinal microbiota and behavioral changes may shed light on the mechanistic connections between dietary interventions, the intestinal microbiome, and intestinal neurological function of the host organism.
Current Opinion in Biotechnology 2015, 32:v–viii
New prebiotics and probiotics with varying functions are emerging and this can be expected to expand in the future. Understanding the function and mechanism of these health promoting bioactives is important to support the health claims associated with their consumption. Regulation governing the introduction and use of new prebiotics and probiotics may include safety concerns depending on the nature of the bioactive used, but will in all cases evaluate the evidence presented to support the corresponding health claim. The contribution written by Kumar et al. includes a group of expert-authors from different parts of the world, and summarizes the different regulatory context in the different global market regions (European Union, United States, Canada and Japan). Examples are evaluated for some of the novel prebiotics and probiotics that were recently evaluated within the EU legislation system. Moreover, the authors present a list of scientific requirements for safety assessment and regulation of novel probiotics, as a helpful addition to the WHO/FAO guidelines 2002.
www.sciencedirect.com
ScienceDirect Editorial overview: Food biotechnology: Microbial ecosystem management: strategies to adapt ecosystems to improve performance and health impact Michiel Kleerebezem and Christophe Lacroix Current Opinion in Biotechnology 2015, 32:v–viii For a complete overview see the Issue Available online 27th February 2015 http://dx.doi.org/10.1016/j.copbio.2015.02.009 0958-1669/# 2015 Elsevier Ltd. All rights reserved.
Michiel Kleerebezem
Host Microbe Interactomics Group, Department of Animal Sciences, Wageningen University, The Netherlands e-mail: [email protected] Michiel Kleerebezem is professor of Host Microbe Interactions, at the Department of Animal Sciences of Wageningen University as well as Principal Scientist at the Health Department of NIZO food research. His research expertise centers around the molecular biology and physiology of bacteria, with a special focus on lactic acid bacteria, probiotics, and the intestinal microbiota. In recent years he has expanded his field to the (post-genomic) molecular analysis of the mechanisms of communication between intestinal bacteria and the host mucosa. His work aims to understand and improve the functional performance of starter cultures for industrial fermentation and probiotic application, while his work on the intestinal microbiota and probiotics strives to decipher the molecular cross-talk between these intestinal microbes and the host’s mucosa in order to enhance their application potential for the benefit of human and animal health.
www.sciencedirect.com
Microbes and their ecosystems are intimately connected to our life, environment, food and health. Microbes of our body, particularly the gut microbiota, provide many essential functions related to development, immunity, digestion, nutrition and pathogen protection. Probably the biggest challenge facing humanity is our capacity to feed the world, with an expanding and ageing population. Moreover, the United Nations World Food Program, estimated that more than 870 million people are malnourished. Many of these people are children, leading to approximately one out of six children being underweight, and knowing that malnutrition contributes to the death of 2.6 million children each year. At the same time, approximately one-third of all available food products is wasted. Feeding a global population that is projected to reach 9 billion by 2050 will require an increase of agricultural yields by 70–100%, but also demands major food innovations aimed to nourish Man’s health, by preventing and treating the expanding chronic diseases. In view of these requirements it is crucial to improve our understanding of the roles fulfilled by microbes and ecosystems in the environment and food production processes, but also those associated with our own body. Such understanding is crucial to harness the tremendous potential of microbes in food processing, nutrition and health. Over the past years, considerable advances have been made in characterizing composition and roles of microbes in food and in the human gut. Tremendous advances in life sciences supported by next generation sequencing (NGS) that fuels (meta-)genomics, as well as high-resolution metabolomics are revolutionizing our understanding of microbes and ecosystems associated with nutrition and health. These advances have led to groundbreaking discoveries in novel functions of microbes in food and humans. This includes functions related to production of safe, sustainable and healthy fermented foods as well as health-promoting microbes and other food ingredients. The intestinal microbiota research is starting to decipher how food and food ingredients may support pathogen protection, restoration of gut microbiota balance and diversity, and nutrient digestion and conversion, which in the long run could contribute to the prevention or correction of a broad range of chronic diseases, including those related to inflammation and immunity (IBD, IBS, [food-] allergy, autoimmunity, etc.), metabolism (obesity, diabetes, etc.), and/or even neurology (Parkinson, autism, etc.). However, causality, underlying mechanism, and nutritional strategies for microbiota modulation are still to be demonstrated. The high biodiversity of the intestine provides a unique source of microbial capacities, encompassing known and many still to be discovered functions. Molecular methods have tremendously contributed to our understanding of the genetic and metabolic Current Opinion in Biotechnology 2015, 32:v–viii
vi Food biotechnology
Christophe Lacroix
Laboratory of Food Biotechnology, Institute of Food Science and Nutrition, ETH Zurich, Switzerland e-mail: [email protected] Christophe Lacroix is Professor for Food Biotechnology, Department of Health Science and Technology, at the Swiss Federal Institute of Technology Zurich. His main research interests include the fundamental and technological characterization of functional microbes and their roles in food and intestinal ecosystems, with multidisciplinary system-oriented aspects. This includes ecosystem study and microbe screening and characterization, functional studies and mechanisms, microbial technology, and intestinal research (from in vitro modeling to in vivo human studies). In his teaching, he aims to bridge basic knowledge of natural sciences and engineering sciences in order to achieve the application of microorganisms, enzymes and metabolites for processing of high quality, safe and healthy food and functional ingredients.
potential of the intestinal ecosystem. However, harnessing the potential of microbiota for the improvement of health, still requires their cultivation and functional characterization. This is a challenging task for strict anaerobes, and using cultivation techniques that were mainly developed in the sixties, which may recover less than 30% of the overall intestinal microbes. This challenge certainly extends to efficient large scale production and processing of gut microbes for health-promoting supplement applications, but also impacts our capacity to rationally design dietary ingredients aiming to stimulate health-supporting microbiota, or even correcting the unbalanced microbiota correlated with disease. Imposing selective environmental pressures on microorganisms may be exploited to deliberately adapt microbes to environmental niches or industrial processes in which they are applied, selecting for improved industrial performance in food fermentation processes or enhanced functionality within microbial ecosystems. Inversely, environmental challenges can also cause unbalanced, dysbiotic ecosystems with undesirable phenotypes, such as accumulation of resistance genes upon antibiotic treatment, or an inflammation stimulating microbiota in the obese host. The microbial communities adapted to the intestinal ecosystem can be modulated by altering the physicochemical conditions of such habitat by nutritional interventions. Nutritional factors such as fibers, exogenous microbes, and other dietary compounds have not yet been fully investigated for their potential to enhance microbiota fitness, and to prevent or correct non-homeostatic (dysbiotic) host-microbe interactions in human disease. Intestinal microbiota modulations by food hold the potential to influence human health in a variety of domains, including nutritional, metabolic, and immune status with impact on both intestinal — as well as systemic health. In this issue on food biotechnology, the ten excellent contributions address the current status of knowledge of microbial fitness in food production and intestinal microbiota–host interactions, and how this can impact on industrial food-production and ingredient-production, and/or the intestinal microbiota and host health.
From fermented foods, to intestinal microbiota–host interactions, and novel prebiotics and probiotics Our understanding of the molecular changes underlying microbial evolution has been accelerated tremendously by NGS genomics, providing holistic information of the genetic changes that drive the adapted behavior of evolving microbes. Bachmann et al. highlight the revival of experimental evolution strategies for the production of industrial strains with improved fermentation performance and/or enhanced environmental fitness. Recent developments in single cell technologies such as those relying on microfluidics, combined with NGS are fueling the comprehensive character of such approaches and enable improved experimental designs to obtain desired phenotypes. Sustainable performance of microbes in industrial fermentation depends on the effective prevention of phage predation. Mahony and van Sinderen describe the recent advances in the molecular understanding of phage-host recognition and the characterization of the docking molecules involved can open novel avenues for prevention of problems associated with phages in industrial fermentation. Moreover, improved understanding of phage diversity and its mechanisms of interaction with its microbial host may also revive the concept of phage therapy, for example to eradicate food-borne pathogens from products. Current Opinion in Biotechnology 2015, 32:v–viii
www.sciencedirect.com
Editorial overview Kleerebezem and Lacroix vii
The development of NGS has revolutionized our understanding of the human intestine microbiota and its relationship with health and disease. The diet is one of the main drivers of gut microbiota establishment and functionality, since it provides the main source of nutrients for the microbes residing in the small intestine and the colon. The (changes in) dietary habits during the first 2–3 years of life importantly shape the gut microbiota of infants, which may have long term, life-span encompassing health impacts. Dore´ and Blottie`re highlight recent developments showing the complex connections of dietary factors, microbiota and host health, and underpinning the importance of microbiota richness as an important homeostasis supporting factor. Understanding mechanisms and effects beyond description could pave the way for rational ingredient design and diet consumption, exemplified by fibers, to prevent or correct loss of symbiosis by stimulation of microbiota resilience and richness. Most research on the intestinal microbiota has targeted the numerically dominant microbes of the human (or animal) large intestine. Much less is known about the small intestine microbiota, although both the physiological function of this part of the intestinal tract as well as a number of recent studies support a prominent role of the small intestine microbiota in modulation of the host’s physiology and health. El Aidy et al. present the most recent advances on the human small intestine microbiota and its effects on immune, metabolic, and endocrine functions. Studying this part of the intestinal tract remains challenging due to its poor accessibility and the relatively high invasiveness of procedures for sampling. However, the modulation of the small intestine microbiota by diet provides a feasible and promising target, which may enable enhancement of both local and systemic immune, endocrine and metabolic processes that beneficially impact on host health. Prebiotics, defined as ‘non-digestible food components that exert specific stimulation of gut bacteria, for beneficial effect on the host’, are among the dietary ingredients targeted to modulate the intestinal microbiota. Rastall and Gibson expand the view on prebiotics beyond the classical prebiotic fructans and galactans that have been well studied for their effect on intestinal bifidobacteria, towards other candidate prebiotics that are investigated. These food ingredients may eventually target a broader range of beneficial gut bacteria and are investigated in an expanding range of health-benefits, including their prophylactic and therapeutic potential in immune-diseases and metabolic-diseases. Prebiotics may derive from biosynthetic processes using enzymatic polymerization of simple sugars or may be generated by controlled hydrolysis of complex polysaccharide-containing materials of plants or agricultural and/or food processing waste streams. To eventually support prebiotic health-claims, it is of critical importance to demonstrate their specificity www.sciencedirect.com
in microbiota modulation and the corresponding health promoting mechanisms. Probiotics classically refer to food-grade microbes that are consumed in alive to confer a health benefit to the consumer. Many of the currently marketed products contain lactobacilli or bifidobacteria, although also probiotics of other genera are available. The expanding association of specific intestinal microbial species with health, and the success of fecal microbiota transplantation in some disease treatments, has fueled the interest in the preparation of specific, or mixtures of intestinal microbial species for their application as next-generation probiotics. Claes et al. evaluate the status of this field and exemplify that adequate knowledge of the mechanism of action of classical and/or next generation probiotics is critical to predict their health potential. Moreover, these authors also underline the importance of stratification of the target population for the prediction of the efficacy of microbial intervention, as well as the need for multivariate analyses to establish its impact on host physiology. The concept of next-generation probiotics is placed in the context of their possible role in therapeutic approaches in metabolic syndrome patients. Cani and van Hul highlight the potential of probiotic therapies in the treatment of obesity and/or associated disorders like diabetes. Several studies report on the beneficial impact of classical probiotic lactobacilli and bifidobacteria and/or other species (including the yeast probiotic Saccharomyces cerevisiae var. boulardii) on physiological parameters of the host associated with metabolic syndrome, including body weight and fat-mass reduction, suppression of hepatic and adipose tissue inflammation, etc. The importance of bile acids as signaling molecules in regulation of the host’s energy, glucose and fatty acid metabolism may provide rational selection strategies for more effective probiotics, for example based on their bile hydrolyzing capacities. Finally, the authors describe the recent findings related to a possible role of the intestinal microbe Akkermansia municiphila in controlling host metabolism and its potential as a next generation probiotic in the treatment of metabolic syndrome. Mechanisms of dietary factors on gut microbiota and gut health are still poorly understood despite continuous expansion of metadata generated by large scale projects all over the world. Lacroix et al. highlight the importance of the rational combination of investigations using suitable in vitro and in vivo models and human trials to provide mechanistic understanding of health-promoting nutrient function. Recent developments in in vitro and in vivo models, but also the limits of individual modeling strategies, are exemplified, arguing in favor of the combination of various models. Overall, multi-scale strategies that include human trials, with optimal selection and design of each step, offer great potential for advancing Current Opinion in Biotechnology 2015, 32:v–viii
viii Food biotechnology
knowledge on the role of intestinal microbiota and the effects of dietary factors in the healthy and diseased host. A more recent and very exciting area of host health for which a role of the intestinal microbiota has been postulated is related to brain function and behavior. The past years neuroscience research has shown the importance of the microbiota in brain development and its influence on stress associated behavior. Luna and Foster highlight recent advances in studies evaluating the impact of diet induced changes in the microbiota on stress-related behavior like anxiety and depression. The authors underline the potential of targeted dietary interventions using probiotics and prebiotics to beneficially influence behavior. Mechanistic understanding in this area is still in its infancy, and the authors propose that especially host metabolomic analysis in relation to intestinal microbiota and behavioral changes may shed light on the mechanistic connections between dietary interventions, the intestinal microbiome, and intestinal neurological function of the host organism.
Current Opinion in Biotechnology 2015, 32:v–viii
New prebiotics and probiotics with varying functions are emerging and this can be expected to expand in the future. Understanding the function and mechanism of these health promoting bioactives is important to support the health claims associated with their consumption. Regulation governing the introduction and use of new prebiotics and probiotics may include safety concerns depending on the nature of the bioactive used, but will in all cases evaluate the evidence presented to support the corresponding health claim. The contribution written by Kumar et al. includes a group of expert-authors from different parts of the world, and summarizes the different regulatory context in the different global market regions (European Union, United States, Canada and Japan). Examples are evaluated for some of the novel prebiotics and probiotics that were recently evaluated within the EU legislation system. Moreover, the authors present a list of scientific requirements for safety assessment and regulation of novel probiotics, as a helpful addition to the WHO/FAO guidelines 2002.
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