The Science, Microbes & Health Podcast 

This podcast covers emerging topics and challenges in the science of probiotics, prebiotics, synbiotics, postbiotics and fermented foods. This is the podcast of The International Scientific Association for Probiotics and Prebiotic (ISAPP), a nonprofit scientific organization dedicated to advancing the science of these fields.

Identifying features of a healthy microbiome, with Raphaela Joos

This episode features Raphaela Joos from University College Cork in Ireland, speaking about efforts by the Human Microbiome Action Consortium to create an expert-led consensus around the concept of a healthy human microbiome. Ms. Joos, a PhD student who was first author of the resulting paper, notes that a healthy human microbiome can be defined at many different levels. Some parameters such as diversity and resilience are good for a microbial community, and other parameters such as antimicrobial resistance are good for the microbial community but not necessarily good for the host. Another challenge with the definition was how to define health. The group decided that the definition of healthy microbiome needed to be more inclusive than just the microbiome of a healthy person with no disease diagnoses. At present, causality is not clear so we don’t know whether disease-associated microbiomes are adaptive or are driving the disease. The main consensus that emerged from this expert discussion was that more data are needed, tracking large cohorts of people over time in many geographical areas. Only in this way will it be possible to overcome individual variability and truly identify the robust features of a healthy microbiome. Different microbiome compositions can have similar functional capacities, so possibly a functional signature will emerge.

Episode abbreviations and links:

About Raphaela Joos:

Born and bred in Germany, I obtained my BSc in Psychology with a focus on biological neuropsychology, nutrition and statistics at Leiden University and the University of Melbourne. Fascinated by nutritional science and its impact on mental health, I then pursued a MSc on the topic of Microbiome in Health and Disease at King’s College London, delving into microbiology, bioinformatics and microbiome science. After the masters I moved to Cork for a research assistant position investigating the structure and infection mechanisms of bacteriophages involved in cheese fermentation using the protein-folding software AlphaFold. Before starting my PhD, I worked as a project manager under Prof Paul Ross and Prof Aonghus Lavelle on the Human Microbiome Project, organising a workshop featuring international leaders in microbiome research to establish a roadmap to define a healthy microbiome. My PhD now focuses on investigating the role of the infant microbiome in development, applying statistical modelling strategies to integrate functional microbiome data with clinical data.

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Advancing gut microbiome testing for use in clinical practice, with Dr. Gianluca Ianiro MD PhD

This episode features Dr. Gianluca Ianiro MD PhD, a gastroenterologist from the Fondazione A. Gemelli IRCCS and Università Cattolica del Sacro Cuore in Rome (Italy), speaking about how to advance gut microbiome testing for use in medicine. His interest in the gut microbiome began with the clinical observation that fecal microbiota transplantation (FMT) was remarkably successful at curing recurrent C. difficile infection – and from there, he began a program of research on FMT. Current gut microbiome tests are widely variable and don’t provide any clinically relevant information, but some people do them out of curiosity. Over the years it’s become increasingly clear that gut microbiome testing must be standardized to move toward clinical utility. Dr. Ianiro co-authored a recent consensus paper on the challenges of gut microbiome testing and how to move toward standardization. He describes several initiatives that aim to standardize and validate gut microbiome testing, from sample collection to analysis. Dr. Ianiro says promising data exist for gut microbiome testing to predict colorectal cancer, to predict the response to some cancer treatments, and to diagnose inflammatory bowel disease. The field is moving toward some important factors that define a microbiome as “healthy”, but these need to be associated with a clear health outcome if they’re eventually to be used in clinical practice.

Episode abbreviations and links:

About Dr. Gianluca Ianiro MD PhD:

Gianluca Ianiro is a gastroenterologist at the Digestive Disease Center of the Fondazione A. Gemelli IRCCS and adjunct professor in gastroenterology at the Università Cattolica del Sacro Cuore in Rome, Italy.

He has since gone on to establish himself as a key clinical and translational investigator focusing mainly in the field of intestinal microbiota, and has received several research grants in support of his innovative research. His current research is focused mainly on disentangling the rules of donor microbiome engraftment, on investigating microbiome diagnostics and therapeutics in noncommunicable disorders (including cancer), and on bringing microbiome into clinical practice.

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Archive Highlight: Human milk oligosaccharides in the infant gut, with Dr. Simone Renwick PhD

In this episode, the ISAPP hosts discuss human milk and the infant gut with Dr. Simone Renwick PhD from Mother-Milk-Infant Center of Research Excellence (MOMI CORE) at UC San Diego, USA. Dr. Renwick talks about her work investigating how communities of microbes versus individual microbes in the infant gut metabolize human milk oligosaccharide (HMO) structures, and what we know about the origin and functions of the microbes contained in human milk.

Key topics from this episode:

  • Dr. Renwick studies how components of human milk foster the development of the infant gut microbiota. These components include HMOs (special sugars found in human milk) and the milk microbiota.
  • HMOs cannot be metabolized by the human body, but when microbes in the infant gut break them down, it has health benefits for the infant (because infants who receive no human milk are predisposed to a range of diseases).
  • Dr. Renwick used in vitro models to mimic infant microbiota communities, and found that these communities rapidly degraded the HMOs. This metabolism increased microbes associated with health and suppressed potentially pathogenic microbes. 
  • Although most research on HMOs focuses on bifidobacteria that are specially equipped to break them down, she looked at individual strains within the infant gut community and found approximately 100 species capable of directly degrading HMOs.
  • Once breastfeeding ceases, some microbes in the infant gut adapt to different sources of sugars, but others greatly decrease in abundance.
  • Microbes act differently in a community than on their own. Within a complex community, microbes that are better equipped to degrade the HMOs will act quickly, producing byproducts that are then are available to other members.
  • All of the different in vitro models have their advantages and disadvantages. The spatial relationships of the human body are often missing in in vitro models.
  • Humans appear to have the highest concentration of milk oligosaccharides of any mammal.
  • The milk microbiota is another active area of investigation. Live microbes are present in the mammary gland, but their source is still unknown. They tend to resemble the composition of the microbiota on the skin as well as the infant oral cavity, but curiously, anaerobic bacteria are also found in the milk microbiota. Somehow these microbes may move from the mother’s gut to the milk. These microbes may not directly metabolize HMOs. (See this paper.)
  • Formula companies are beginning to put HMO structures into their products – mainly 2′-Fucosyllactose.

Episode links:

About Dr. Simone Renwick PhD:

Dr. Simone Renwick is the Milk & Microbes postdoctoral fellow at the Mother-Milk-Infant Center of Research Excellence (MOMI CORE) at the University of California, San Diego, USA. Her research focuses on understanding the role of human milk components, such as the human milk oligosaccharides (HMOs) and milk microbiota, in fostering the developing infant gut microbiota. She is also interested in the potential therapeutic applications of milk components in diseases that affect adults. Currently, Simone is supervised by Drs. Lars Bode, Rob Knight, Pieter Dorrestein, and Jack Gilbert. Prior to her postdoc, Simone completed her PhD in Molecular and Cellular Biology (MCB) at the University of Guelph, Canada, under the supervision of Dr. Emma Allen-Vercoe.

She was the recipient of the Students and Fellows Association poster prize at the ISAPP 2023 meeting in Sitges, Spain.

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How a non-industrialized diet affects gut microbes and health, with Dr. Anissa Armet PhD RD

This episode features Dr. Anissa Armet PhD RD from the University of Alberta in Canada, speaking about the impact of diet on both the gut microbiota and overall health. Dr. Armet, a registered dietitian and researcher, says the Western diet along with the associated gut microbiome changes have played a role (amongst other things) in the rise of autoimmune diseases in industrialized societies. Dr. Armet describes a recent dietary study she and her collaborators published, for which they created a very high fiber diet called the Non-Industrialized Microbiome restore (NiMe, pronounced “nee mee”) diet. They created recipes and meal plans based on what some non-industrialized populations in the world typically consume, which included 45 grams of dietary fiber per day, and only small portions of animal proteins and dairy products. The participants in this controlled feeding trial saw substantial cardiometabolic benefits as well as certain changes in the gut microbiota after three weeks on the diet. Interestingly, the diet initially reduced the diversity of participants’ gut microbiota, likely because of increased pH in the gut, but diversity rebounded toward the end of the trial. The researchers also introduced a strain of L. reuteri isolated from the gut microbiota of people in a non-industrialized society, to observe whether it would engraft since the diet was known to contain growth substrates for the bacteria. Although the strain did not engraft in the gut microbiota (except in one participant), the health benefits of the diet overall were still observed. The researchers concluded that the NiMe diet can be used to target the gut microbiome and change community characteristics that are relevant for health.

Episode abbreviations and links:

About Dr. Anissa Armet PhD RD:

Dr. Anissa Armet is a Registered Dietitian and postdoctoral researcher at the University of Alberta. Anissa completed her PhD in Nutrition and Metabolism in March 2024, then transitioned into her postdoc to research the effects of microbiome-targeted dietary interventions in inflammatory bowel diseases. She uses machine learning to determine if the gut microbiome predicts clinical responses in the context of precision nutrition. Anissa has authored several peer-reviewed publications, including a review on healthy eating in light of the gut microbiome and a dietary intervention trial on microbiome restoration. Being equally passionate about knowledge translation, Anissa co-authored an award-winning, open-access, high-protein cookbook designed to support muscle health, is currently developing a plant-based version, and recently co-authored an open-access ebook, The NiMe Diet: Scientific Principles and Recipes.

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Interactions of polyphenols in the gut, with Prof. Yves Desjardins PhD

This episode features Prof. Yves Desjardins PhD from Laval University in Canada. Prof. Desjardins, an agrologist by training, explains that polyphenols are metabolites synthesized by plants and present in the plant foods we consume. When humans consume polyphenols, we absorb a small fraction (around 5%) of them in the upper gastrointestinal tract, but most of them reach the colon and interact in various ways with the gut microbiota. They have two main effects in the gut, which appear somewhat contradictory: antibacterial effects and a prebiotic-like effect. In the latter case, polyphenols interact with the host epithelium to induce mucin production, creating a niche for certain bacteria to grow. Typical bacteria that increase under these circumstances are bifidobacteria and Akkermansia muciniphila. In these ways, polyphenols have an impact on certain microorganisms and on the microbiome as a whole. In the future, supplements with polyphenols and fiber may be designed to help manipulate the microbiome in a certain way. Currently there are many health benefits associated with polyphenols. The primary benefit is for cardiometabolic health, and some studies also show benefits for cognition.

Episode abbreviations and links:

About Prof. Yves Desjardins PhD:

Yves Desjardins is a full professor at the Institute of Nutrition and Functional Foods, Laval University, Québec, Canada. He holds the NSERC/Symrise Partnership Chair on the prebiotic effects of polyphenols (PhenoBio+). Trained in plant physiology, his research focuses on the phytochemistry and functionality of plant bioactives. He has led numerous preclinical and clinical studies on type-2 diabetes, cognitive decline, inflammation, and infections. His current work explores the impact of tannins on gut microbiota, mucosal immunity, and gut barrier function. He has collaborated with the food industry to validate the health benefits of horticultural products (e.g., Urophenol, Glucophenol, Neurophenol). Recognized for his innovative research on fruit polyphenols, he chaired the first International Symposium on Health Effects of Fruits and Vegetables (FAVHEALTH 2005), the OECD Symposium in Lisbon (2010), and organized the 2017 International Congress on Polyphenols and Health in Québec City.

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The interplay between gut microbiota, diet, and circadian rhythms, with Dr. Vanessa Leone PhD

This episode features Dr. Vanessa Leone PhD from the University of Wisconsin – Madison on how gut microbes and eating patterns impact the host circadian system and overall health. In mouse models, Dr. Leone has found that in a 24-hour period, minor changes occur in the composition of the gut microbiota, while more important changes occur in gut microbiota function (that is, metabolite production). However, these changes depend on the type of diet and the timing of meal consumption. Metabolic health is also affected by this interplay. In humans, obesity is correlated with loss of microbiota rhythmicity, although causality remains unclear. One study by Dirk Haller found that a loss of rhythmicity helped predict which people with prediabetes would progress to diabetes. Constantly shifting timezones (or shifting between day and night shifts) appears to be more detrimental to metabolic health than maintaining a constant schedule, and research is ongoing about what might mitigate these effects. In this field of research it’s important to consider people’s chronotype: their tendency to rise early versus stay up late. In the future, Dr. Leone hopes to untangle more about how different factors affect metabolic health: diet, gut microbiota, and the circadian system.

Episode abbreviations and links:

About Dr. Vanessa Leone PhD:

Vanessa A. Leone, Ph.D. is an Assistant Professor in the Department of Animal & Dairy Sciences at the University of Wisconsin-Madison, where she also obtained a Ph.D. She performed postdoctoral studies and was an Instructor of Medicine at the University of Chicago in the Section of Gastroenterology, Hepatology, & Nutrition where she examined how the gut microbiome impacts complex metabolic  diseases. Dr. Leone currently studies how day vs. night oscillatory patterns of gut microbes influence the body’s internal clock and metabolism. She hopes to mechanistically define what constitutes a microbial oscillator versus a non-oscillator, examine how host factors impact the broader diurnal structure and functional outputs of the gut microbiome, and to determine how microbial oscillations impact host metabolism. These findings will likely pave the way to identify how timed delivery of pre-, pro-, or postbiotics can be leveraged to promote a balanced gut microbiota and improve host health.

 

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An overview of precision fermentation, with Prof. William Chen PhD

This episode features Prof. William Chen from Nanyang Technological University in Singapore, speaking with the ISAPP hosts about precision fermentation. In Singapore, enhancing national food security is of interest and one of the technologies used to achieve this is precision fermentation. Prof. Chen describes the differences between traditional fermentation, biomass fermentation, and precision fermentation. In precision fermentation, food scientists use genetically modified microorganisms to produce a food ingredient of interest. In some cases the product is secreted out of the cell, and in other cases it must be extracted from the cell. The approach has great potential to bypass the need for a large amount of land to produce food, and may reduce costs associated with food production. As this approach continues to develop, education and transparency with consumers is key. Regulatory frameworks and approval processes differ from country to country, and this is an area that will continue to evolve in the years ahead as more food ingredients or other useful products are generated.

Episode abbreviations and links:

About Prof. William Chen PhD:

William Chen is the Michael Fam Endowed Professor and Director of Food Science & Technology Programme at Nanyang Technological University Singapore. He is concurrently Director of Singapore Future Ready Food Safety Hub (FRESH). He is also Director of Singapore Agri-food Innovation Lab.

Professor Chen is active in securing and leading large competitive research grants from major government agencies as well as leading international food companies. His food technology innovations have been extensively attracting global attention. His views on food tech innovations, food safety and food security have been regularly covered by major local and international media outlets. He is also advisor/consultant to overseas universities, Singapore government agencies, food industry, and international organizations (ADB, FAO, WHO among others).

Precision fermentation for animal-free milk, with Dr. Abigail Thiel PhD

This episode features Dr. Abigail (Abbey) Thiel PhD, who works remotely (from the US) with Wageningen University to manage a project focused on developing animal-free milk proteins using precision fermentation. Dr. Thiel explains that the motivation for the project is to find alternatives to animal-produced foods using microorganisms to produce key components of dairy products. Her project focuses on producing the protein casein, which is found in milk (and contributes to its structure and stability), to eventually produce a milk substitute or a protein powder that could be used as a food ingredient. A specific yeast is used to produce the casein: the scientists insert directions for making the protein into the yeast, then put it in a bioreactor to produce the protein. After that, they figure out how to purify the protein so it can be used in various applications. The final step is upscaling the process to produce abundant and cost-effective casein. The group has also started initial digestion studies to see how the purified casein is digested. Meanwhile, Dr. Thiel is passionate about food science communication and has a YouTube channel called Abbey the Food Scientist, where she strives to build awareness of food science as a career and also to address myths about food science.

Episode abbreviations and links:

About Dr. Abigail Thiel PhD:

Abigail (Abbey) Thiel is a food scientist, educator, and project manager of research focused on producing milk proteins using yeast. She earned her PhD in Food Science from the University of Wisconsin-Madison and later worked as a postdoctoral researcher at Wageningen University & Research in the Netherlands. Abbey is passionate about making the science behind food accessible to all. She runs a successful YouTube channel with over 1.4 million views, breaking down food science concepts for everyday audiences, and created an online course, Food Science for Beginners. In addition, she develops high school curriculum and educational resources to help students explore food science as a career path.

Archive Highlight: An evolutionary perspective on fermented foods, with Assoc. Prof. Katie Amato

Continuing in the series on the latest fermented food science, we are highlighting Episode 9 from our archives. In this episode, the ISAPP hosts talk about fermented foods and non-human primates with Katie Amato of Northwestern University, USA. Amato describes what she has learned from studying the gut microbiota of non-human primates and how it relates to our understanding of human and gut microbial co-evolution over time. She also talks about non-human primate behaviors around fermented foods and what they might tell us about the need for human fermented food consumption.

Key topics from this episode:

  • A list of species categorized as non-human primates.
  • Changes in the gut microbiota of primates depend on habitats and available food across different seasons.
  • Primates in captivity have a different gut microbiota from wild ones – for example, animals kept in the zoo have a lower gut microbiota diversity.
  • Fermentation as a process to improve access to nutritional components of food; knowledge about primates’ use of fermentation and their gut microbes can tell us something about early human evolution.
  • Primates may derive benefits from using fermented foods. Consumption of fermented foods (overripe fruits) by primates is linked to certain habitats and climate factors; some non-human primates appear to intentionally leave fruits to ferment before returning to consume them.
  • There are benefits to translating the knowledge obtained from studying gut microbiota of primates to humans. 

 

Episode abbreviations and links:

Dissertation study: The Gut Microbiota Appears to Compensate for Seasonal Diet Variation in the Wild Black Howler Monkey (Alouatta pigra)

Study: Fermented food consumption in wild nonhuman primates and its ecological drivers

Mentors mentioned: Kathy Cottingham, Matt Ayres, David Peart, John Gilbert, Mark McPeek, Craig Layne, Rob McClung.
Steve Ross, Alejandro Estrada, Paul Garber, Angela Kent, Rod Mackie, Steve Leigh, Rob Knight.

Additional resources:

Research on the microbiome and health benefits of fermented foods – a 40 year perspective. ISAPP blog
New ISAPP-led paper calls for investigation of evidence for links between live dietary microbes and health. ISAPP blog

 

About Assoc. Prof. Katie Amato:

Dr. Amato is a biological anthropologist at Northwestern University studying the influence of gut microbes on host ecology and evolution. Her research examines how changes in the gut microbiota impact host nutrition, energetics, and health. She uses non-human primates as models for studying host-gut microbe interactions in selective environments and for providing comparative insight into the evolution of the human gut microbiota. Her main foci are understanding how the gut microbiome may buffer hosts during periods of nutritional stress and how the gut microbiome programs normal inter-specific differences in host metabolism. Dr. Amato is the President of the Midwest Primate Interest Group, an Associate Editor at Microbiome, an Editorial Board member at Folia Primatologica, and a Fellow for the Canadian Institute of Advanced Research’s ‘Humans and the Microbiome’ Program.

Fermented foods and their health benefits, with Dr. Paul Cotter PhD

This episode features Dr. Paul Cotter PhD of TEAGASC in Ireland, talking about the creation of fermented foods and how they can lead to health benefits. A huge array of foods can be fermented, and historically fermentation was used to extend the shelf life of a food that people had an abundance of. Dr. Cotter’s work in the field originally started with a bacteria-killing bacteriocin that had been isolated from kefir, and later moved toward the microbes in fermented foods. Currently he’s interested in comparing the artisanal approach to fermented foods, which leads to somewhat unpredictable results in the final products, with the industrial approach, which leads to more consistent results. In different artisanal fermented foods, which strains are common and which are unique? Potentially some of the strains can be used to confer a health benefit, and even a benefit that’s personalized to an individual. Dr. Cotter sees the role of fermented foods as possibly targeting pre-disease rather than disease if their ability to confer health benefits can be unravelled further.

Episode abbreviations and links:

Additional resources:

ISAPP infographic: Fermented foods

About Dr. Paul Cotter PhD:

Prof Paul Cotter is the Head of Food Biosciences at Teagasc (the Irish Agriculture and Food Development Authority), is a Principal Investigator with the large Irish Research Centres, APC Microbiome Ireland, VistaMilk and Food for Health Ireland and head of microbiology/co-founder of SeqBiome, a microbiome sequencing and bioinformatics service provider. He is a molecular microbiologist, with a particular focus on the microbiology of foods (especially fermented foods), the food systems and of humans, as well as probiotics and postbiotics. Prof Cotter is the author of >400 peer-reviewed, was included in the Clarivate list of highly cited researchers for 2018-2024, received an honorary doctorate from the University of Antwerp in 2024 and is the Field Chief Editor of Frontiers in Microbiology.

How fermented foods can support health and sustainability, with Prof. Christophe Courtin PhD

In this episode, Prof. Christophe Courtin PhD from KU Leuven in Belgium discusses the potential of fermented foods to provide health benefits and create more sustainable food systems. His work focuses in particular on fermenting cereal grains as a way to create products with better properties or enhanced health impact. Fermentation is a form of food processing that can introduce benefits beyond the raw materials used. Prof. Courtin leads HealthFerm, a European project with the aim of generating research on fermentation that supports a transition to more plant-based products in the diet, using wheat, oats, fava bean, and yellow pea. Fermentation can be scaled up both in industrialized countries and in developing countries. More intervention studies are needed to find out the health-promoting components of fermented foods and their mechanisms – although scientists know a fair amount about yogurt and other fermented dairy products, evidence is needed for other types of fermented foods. This episode is part of our series on the latest fermented food science.

Episode abbreviations and links:

Additional resources:

ISAPP blog post: Food of the future: Fermented and sustainable

About Prof. Christophe Courtin PhD:

Prof. Christophe Courtin is a full professor at the Laboratory of Food Chemistry and Biochemistry at KU Leuven, Belgium. His research focuses on cereal constituents, the enzymes that degrade them and microorganisms in cereal processing. The emphasis is on a basic understanding of the structure and properties of these constituents as well as on their technological and health functionality in cereal-based processes and products. Expertise and an extensive network in this area have been built up through over 40 supervised PhDs, projects and national and international collaborations. He coordinates HealthFerm, a 23 partner Horizon Europe project. He is author of 350 peer-reviewed papers (WoS h-index: 69) and inventor on 12 patent families. Recent awards are the Harald Perten Prize (ICC, 2021) and the Belfort Lecture Award (Whistler Centre for Carbohydrate Research, Purdue University, 2023).

Archive Highlight: The science of fermented foods, part 2, with Prof. Bob Hutkins

Continuing in the series on the latest fermented food science, we are highlighting Episode 3 from our archives. The hosts continue their discussion of fermented foods with Prof. Bob Hutkins, University of Nebraska – Lincoln. Prof. Hutkins elaborates on how the microbes associated with fermented foods may confer health benefits, as well as how food scientists choose strains for fermentation. He emphasizes how the live microbes in fermented foods differ from probiotics. Before listening to this episode, it’s recommended that you check out The science of fermented foods, Part 1. 

Key topics from this episode:

  • Why working in the field of fermented foods is exciting and rewarding
  • The challenges for scientists, especially when it comes to designing clinical studies with various fermented foods
  • The benefits of fermented foods – from being safe as well as nutritious, to the health benefits that live microbes present in the foods can provide
  • How microbes are selected for fermentation; companies focus on strain performance – i.e., good growth and survival to preserve the food and provide a desired flavor and texture
  • The activities of live microbes present in fermented foods, from initiating the fermentation process to benefiting human health
  • The differences between probiotics and live microbes in fermented foods
  • How live microbes in fermented foods might affect your gut microbiota and why some scientists believe that fermented foods are important for getting regular doses of live microbes

Episode links:

Additional resources:

About Prof. Bob Hutkins:

Bob Hutkins is the Khem Shahani Professor of Food Microbiology at the University of Nebraska. He received his Ph.D. from the University of Minnesota and was a postdoctoral fellow at Boston University School of Medicine. Prior to joining the University of Nebraska, he was a research scientist at Sanofi Bio Ingredients.

The Hutkins Lab studies bacteria important in human health and in fermented foods. His group is particularly interested in understanding factors affecting persistence and colonization of probiotic bacteria in the gastrointestinal tract and how prebiotics shift the intestinal microbiota and metabolic activities. The lab also conducts clinical studies using combinations of pro- and prebiotics (synbiotics) to enhance health outcomes. More recently we have developed metagenome-based models that can be used in personalized nutrition.

Professor Hutkins has published widely on probiotics, prebiotics, and fermented foods and is the author of the recently published 2nd edition of Microbiology and Technology of Fermented Foods.

Archive Highlight: The science of fermented foods, part 1, with Prof. Bob Hutkins

Welcome to the first episode of our new series on the latest fermented food science. We are highlighting Episode 1 from our archives with guest Prof. Bob Hutkins, University of Nebraska – Lincoln. Prof. Hutkins wrote a popular textbook on fermented foods and has had a 40-year career in fermentation science. He shares why he ended up in fermentation science, as well as how fermented foods are made and how important live microbes are for their health benefits.

Key topics from this episode:

  • What fermented foods are
  • The scientific consensus definition published by ISAPP
  • Fermentation processes and practices used in early times and still used today
  • The benefits and safety of fermented foods, as well as the difference between fermentation and food spoilage
  • The live microbes present in fermented foods, how many are present, and their potential health benefits
  • Why some fermented foods have live microbes and others do not; and how even when live microbes are absent due to heat treatment, for example, these products may still be classified as fermented 
  • The differences between fermented foods, probiotics, and probiotic fermented foods

Episode links:

Additional resources:

About Prof. Bob Hutkins:

Bob Hutkins is the Khem Shahani Professor of Food Microbiology at the University of Nebraska. He received his Ph.D. from the University of Minnesota and was a postdoctoral fellow at Boston University School of Medicine. Prior to joining the University of Nebraska, he was a research scientist at Sanofi Bio Ingredients.

The Hutkins Lab studies bacteria important in human health and in fermented foods. His group is particularly interested in understanding factors affecting persistence and colonization of probiotic bacteria in the gastrointestinal tract and how prebiotics shift the intestinal microbiota and metabolic activities. The lab also conducts clinical studies using combinations of pro- and prebiotics (synbiotics) to enhance health outcomes. More recently we have developed metagenome-based models that can be used in personalized nutrition.

Professor Hutkins has published widely on probiotics, prebiotics, and fermented foods and is the author of the recently published 2nd edition of Microbiology and Technology of Fermented Foods.

2024 highlights in biotic science, with ISAPP’s current and past Presidents

In this episode, ISAPP’s current President Prof. Maria Marco PhD and past President Prof. Dan Merenstein join the podcast hosts for a conversation about highlights in biotic science from the past year. Prof. Marco points out a paper published in Nature Microbiology, the result of an ISAPP discussion group exploring whether diet may be a confounder of biotic effects in clinical studies. The group concluded that scientists should work with dietitians to include data on participants’ habitual diet in future studies on biotics – particularly with on prebiotics. These efforts will help scientists establish causality and understand the basis of individual responses to a biotic intervention. Prof. Merenstein highlighted conversations in 2024 around the role of probiotics in the neonatal intensive care unit (NICU), including ISAPP’s panel on this topic at the annual meeting in Cork, Ireland. Although US regulators have recently warned against the use of probiotics for preterm infants in the NICU setting, the data overwhelmingly points to benefits and this may eventually drive regulatory change. Prof. Marco added that a take-away from ISAPP’s panel was that parents of preterm infants should be included in the decision-making around whether to use probiotics. The guests talked about Prof. Merenstein’s recent appointment to the National Academy of Medicine and his rigorous approach to primary care research. Further highlights in the science this year were ISAPP’s papers exploring evidence for probiotics restoring an antibiotic-disrupted microbiota, and evidence for the benefits of probiotics in healthy individuals – both of which found a lack of conclusive evidence to answer these questions. Many gaps exist in the knowledge around biotics, gut microbiota, and health – for example, another paper this year found that the abundance of microorganisms in a fecal sample is a confounder of microbiome-disease associations. And finally, beyond the scientific advancements, conveying the scientific concepts to the general public requires careful consideration and dedicated effort.

Episode abbreviations and links:

About Prof. Maria Marco PhD

Dr. Maria Marco, PhD, is a Professor in the Department of Food Science and Technology at the University of California, Davis. She earned her bachelor’s degree in microbiology at The Pennsylvania State University and her PhD in microbiology at the University of California, Berkeley. As a postdoc at NIZO food research in The Netherlands, she developed a love for lactic acid bacteria and the importance of these microorganisms in our foods and the digestive tract. Her postdoctoral studies led to the discovery that probiotics are metabolically active in the intestine and responsive to dietary intake. Dr. Marco started her lactic acid bacteria and gut health laboratory at UC Davis in 2008 and has built an internationally-recognized, NIH, USDA, and NSF funded research program on probiotics, fermented foods, and dietary modulation of the gut microbiome. Dr. Marco also consults with and has received funding from international foundations and companies to investigate how certain microbes in foods or supplements may benefit health. She is active with science communication activities such as the EATLAC project and is the instructor for two food microbiology courses. Dr. Marco received the American Society for Microbiology Distinguished Lecturer award in 2012. Recently, she founded the ongoing Gordon Research Conference series on Lactic Acid Bacteria. Dr. Marco attended her first ISAPP meeting as a postdoc and participated as an invited expert before joining the ISAPP Board of Directors in 2019.

About Prof. Dan Merenstein

Dr. Daniel Merenstein, MD, is a Professor with tenure of Family Medicine at Georgetown University, where he also directs Family Medicine research. Dr. Merenstein has a secondary appointment in the undergraduate Department of Human Science, in the School of Health. Dr. Merenstein teaches two undergraduate classes, a research capstone and a seminar class on evaluating evidence based medical decisions. He has been funded by PCORI, NIH, USDA, foundations and industry. The primary goal of Dr. Merenstein’s research is to provide answers to common clinical questions that lack evidence and improve patient care. Dr. Merenstein is a clinical trialist who has recruited over 2,000 participants for 10 probiotic trials since 2006. He is an expert on probiotics, on antibiotic stewardship in outpatient settings, and also conducts HIV research in a large women’s cohort. He sees patients in clinic one day a week. Dan lives in Maryland with his wife and 4 boys.

Gut microbes and other drivers of inflammation in Parkinson’s disease, with Prof. Malú Tansey PhD and Dr. Andrea Merchak PhD

This episode features Prof. Malú Tansey PhD and colleague Dr. Andrea Merchak PhD from the University of Florida, USA, discussing neuroinflammation and the role of gut microbes in Parkinson’s disease (PD) and other neurodegenerative diseases. “Inflammaging” tends to occur as aging progresses, but the links that have been made between the gut and the brain in PD have led their group to the hypothesis that PD may be an age-acquired autoimmune condition. Genetic factors are relevant, although not everyone with PD has the predisposing genes. Those with a certain genetic mutation have a different immune phenotype from normal. Furthermore, the gut microbiota influences the immune system and the inflammatory environment within the body, with some metabolites known to cross the blood-brain barrier and influence the immune cells of the brain. Currently the group is focusing on using the gut microbiome, blood, and colonic biopsies to gain insights into the brain. A combination of diet and probiotics is promising as an intervention to prevent neurodegeneration as people age.

Episode abbreviations and links:

About Prof. Malú Tansey PhD:

Malú Gámez Tansey, Ph.D. is the Norman and Susan Fixel Chair in Neuroscience and Neurology and former Director of the Center for Translational Research in Neurodegenerative Disease at the University of Florida. Her lab focuses on the role of inflammation and immune system responses in brain health and neurodegenerative disease, with particular focus on central-peripheral neuroimmune crosstalk and the gut-brain axis, with the long-term goal of developing better therapies to prevent and/or delay these diseases.

Dr. Tansey obtained her B.S/M.S in Biological Sciences from Stanford University and her Ph.D. in Cell Regulation from UT Southwestern followed by post-doctoral work in neuroscience at Washington University. As head of Chemical Genetics at Xencor, she co-invented novel soluble TNF inhibitors that have now advanced to clinical trials in Alzheimer’s disease. She returned to academia as an Assistant Professor of Physiology at UT Southwestern in 2002 and was recruited to Emory University School of Medicine as a tenured Associate Professor in 2009. After 10 year at Emory and rising to the rank of Full Professor where she earned several mentoring awards

from students and faculty for her efforts in championing early-stage investigators, women and other under-represented groups in STEM, she was recruited to the Department of Neuroscience in the College of Medicine at the University of Florida, where she served on the

executive committees for the McKnight Brain Institute and the Fixel Institute for Neurological Diseases. She will be moving to the Stark Neuroscience Research Institute at Indiana University in Indianapolis in January of 2025 as the first Director of Neuroimmunology Research and Executive Associate Director of Education at the Stark NRI.

About Dr. Andrea Merchak PhD:

Andrea Merchak, Ph.D. is a Gator Neuroscholar Postdoctoral Associate at the University of Florida. She obtained her B.S. at Centre College with a focus on behavioral neuroscience and her Ph.D. from the University of Virginia. There, her thesis work explored the link between the gut microbiota and the brain in mood disorders and multiple sclerosis. Her current work explores the relationship between gut health and genetic predispositions for neurodegeneration. She has received recognition for her work through the Young Scientist Award from the International Prebiotics, Probiotics, and Gut Microbiome Conference, the

Outstanding Graduate Student Award from the University of Virginia, as well as a track record of funding from the NIH. She will be moving to the Stark Neuroscience Research Institute at Indiana University in Indianapolis in March of 2025 as an Assistant Professor of Neurology.

Using a microbiota-gut-brain axis on a microfluidic chip to gain insights into neurodegenerative diseases, with Prof. Kerensa Broersen PhD

This episode features Prof. Kerensa Broersen PhD from University of Twente in the Netherlands, speaking about using an innovative model of the microbiota-gut-brain axis to learn about neurodegenerative diseases such as Parkinson’s disease. Prof. Broersen says that while clinical studies are applicable to human health and animal models have great physiological complexity, her lab focuses on a model that’s more flexible and that allows manipulation of specific signalling events – a microbiota-gut-brain axis on a microfluidic chip. To make the brain component, they use stem cells from healthy people (from bone marrow, blood, or urine), which can differentiate into different types of cells depending on the factors they’re exposed to. They create cells that represent different areas of the brain, and can keep them alive and functional for at least 100 days. They can also represent disease processes in the model. It’s known that the gut microbiota is involved in neurological disease and may be either a cause or consequence of the brain pathology; so in this model, the scientists culture gut microbes in one microfluidic device and the brain in another microfluidic device, then connect the two. This allows them to make changes in one compartment and see how it affects the other. In this way, Prof. Broersen is aiming to understand some of the very basic mechanisms of neurodegenerative disease development and progression.

Episode abbreviations and links:

About Prof. Kerensa Broersen PhD:

Kerensa Broersen obtained a PhD in food chemistry from Wageningen University and Research, the Netherlands, in 2005, followed by two postdoctoral positions at the Medical Research Council in Cambridge, UK and the Free University of Brussels in Belgium, both focussing on protein aggregation in neurodegenerative disorders. She then joined the University of Twente at a tenure track assistant professor position to further investigate neurodegenerative disorders making use of neuronal cell types. Following a sabbatical at the University of California – Berkeley, in the group of Randy Schekman, Kerensa Broersen moved into the field of gut-brain communication studying the fundamentals of signaling pathways driving the intricate interaction between the intestinal microbiome, the gut and the brain. For this, she is making use of the differentiation potential of stem cells to create mini-versions of the organs involved cultured onto microfluidic devices.

Developing probiotics for neurodegenerative disease, with Dr. Alex Parker PhD

This episode features Dr. Alex Parker PhD from Université de Montréal talking about models for studying neurodegenerative diseases. His lab makes use of the worm C. elegans, a common model organism for studying disease and aging as it has many genes in common with humans. Focusing on amyotrophic lateral sclerosis (ALS), Dr. Parker makes models that reflect some aspect of the disease – in this case, genes that are directly linked to ALS are directly expressed in the nervous systems of the worms. Then the lab screens different small molecules from drug collections to see what seems to protect the worms from neurodegeneration. In human ALS, the microbiome is a potential factor that could influence the development of disease if a genetic predisposition is present. Dr. Parker’s lab screened a collection of microorganisms and found one strain that protected the worms from progression of neurodegeneration. Simultaneously, they saw that genes involved in lipid metabolism were being altered. Their work indicates a signaling mechanism from the intestine to the nervous system turns on a protective pathway in the worms – and interestingly, feeding the worms fatty acids directly was not as effective, possibly indicating that the live microorganism is working through multiple pathways. Currently the group is testing the probiotic in mouse models and in an upcoming clinical trial examining how the lipid profile of ALS patients changes as the disease progresses.

Episode abbreviations and links:

About Dr. Alex Parker PhD:

Alex Parker obtained a PhD in Medical Genetics at the University of British Columbia with Dr. Ann Rose using the model organism C. elegans to study Huntington’s disease. From there he did postdoctoral training with Dr. Christian Neri at INSERM, (Paris, France) to develop drug discovery methods for trinucleotide repeat disorders. He is now a professor in the department of neuroscience at the Universite de Montreal, and a researcher at the CRCHUM. His research focuses on developing genetic models for a wide range neurodegenerative diseases with a special focus on amyotrophic lateral sclerosis to find new therapeutic strategies with translation to clinical settings. Recently his team discovered a probiotic that protects against neurodegeneration in animal models and is now part of a clinical trial for ALS.

Archive Highlight: New evidence on the virome in gut-brain communication and stress, with Nathaniel Ritz and Thomaz Bastiaanssen

Continuing our series on the microbiota-gut-brain axis, we are highlighting Episode 34 from our archives. In this episode, the ISAPP hosts discuss a new study on how the gut virome affects the host during stress, with Nathaniel (Nate) Ritz from the Institute for Systems Biology in Seattle, USA and Thomaz Bastiaanssen from APC Microbiome Ireland. The guests give an overview of the microbiota-gut-brain axis, then delve into a new study they led on the virome and its effects on stress responses in mice.

Key topics from this episode:

  • The gut and the brain communicate in various ways, and the microbiota play a role in some of these modes of communication. Various studies use animal models to look at mechanisms that might be applicable to humans.
  • Why would the microbiota affect the human brain? Because we evolved with a ‘background’ of microbes and have relied on them as we evolved. For example, gut microbes produce metabolites the human body is unable to produce by itself.
  • The newly published paper is titled “The gut virome is associated with stress-induced changes in behaviour and immune responses in mice”.
  • Most microbiota-gut-brain axis research to date has looked at the bacterial component of the microbiome, but this misses the bigger context. The virome is the collection of viruses in the gut, mostly consisting of bacteriophages (which infect bacteria in the gut). This study focused on the virome and how it influenced the gut bacteriome as well as host behavior.
  • Bioinformatics challenges exist when working with the virome for several reasons. For one, distinguishing the biology of a bacteriophage from its host can be challenging.
  • The study used a fecal virome transplant: taking a fecal sample, removing the cellular organisms and small particulates so that the bacteriophages were left over, and then concentrating them and administering them. The researchers took this entire virome from a mouse, then transferred it back to the same individual mouse while it was undergoing stress.
  • After stress, differences were seen in the mouse gut bacteriome and virome. The mice had higher anxiety- and depression-like behaviour, plus changes in their immune systems. But after the fecal virome transplant, some of their behaviours were improved.
  • Do the viruses impact the host nervous system directly, or do they only affect the host by way of the bacteriome? This is not fully known, but there appears to be very little interaction of the bacteriophages with the host. 
  • Analysis of the gut bacteriome or virome must respect the compositional nature of the data. The types of measurements used to analyze the microbiome and virome are confounded by compositional effects, and in the field this is not respected as much as it should be.
  • The next step after this study is to explore the changes in microbiome function in the mice, perhaps pinpointing which bacterial groups need to be changed to normalize the mouse behaviours.

Episode links:

About Nathaniel Ritz:

Dr. Nathaniel Ritz completed his PhD in Prof. John Cryan’s lab at APC Microbiome Ireland where he studied the role of the bacteriome and the virome in social and stress-related disorders. His interests lie in elucidating microbiota-host interactions and establishing microbiota causality within the microbiota-gut-brain axis. Nathaniel has recently moved to Seattle, Washington, USA, to join the lab of Dr. Sid Venkatesh as a postdoctoral fellow at the Institute for Systems Biology to further unravel the mechanisms underpinning microbe-host interaction. Outside of the lab, Nathaniel is an avid rock climber, dog walker, and partner to fellow scientist Dr. Minke Nota. More details and current position can be found at https://venkatesh.isbscience.org/

About Thomaz Bastiaanssen:

Dr. Thomaz Bastiaanssen is the lead bioinformatician in Prof. John F. Cryan’s microbiota-gut-brain axis group in Cork, Ireland. He is interested in the ecological dynamics governing host-microbe communication and how this complex interplay can impact human well-being. He will soon transition to a new role at Amsterdam UMC, the Netherlands, where he will continue to study the microbiome gut-brain axis. Besides working on multi-omics analyses, he enjoys horror stories, tabletop games and spending time with his wife, son, and corgi. His website can be found at: https://thomazbastiaanssen.github.io/

Archive Highlight: The role of microbes in gut-brain communication, with Prof. Emeran Mayer MD

 

Continuing our series on the microbiota-gut-brain axis, we are highlighting Episode 26 from our archives. In this episode, ISAPP podcast host Prof. Dan Tancredi PhD welcomes guest Prof. Emeran Mayer MD, a gastroenterologist and researcher at University of California Los Angeles. They talk about the microbiota-gut-brain axis, covering its evolutionary origins and how this complex system works in the human body to support overall health.

Key topics from this episode:

  • Microbiota-gut-brain communication has a long evolutionary history: microbes have been around for billions of years and they stored a lot of information in their genes. At some point in evolution microbes got inside the digestive tube of a primitive marine animal called hydra and it proved advantageous for this animal.
  • The hydra shows the origin of the human enteric nervous system (ENS): microbes live inside this tube and transfer genes to the nerve cells of this digestive tube, showing the origin of neurotransmitters.
  • Today in humans the neurotransmitters influence gene expression of microbes and change the microbial behaviors; the metabolites produced feed back to the brain.
  • Prof. Mayer’s initial interest as a gastroenterologist was the ENS and how it regulates motility. Subsequently the ENS was found to regulate many gut functions. The gut also houses a large part of the immune system and a complex hormonal system, and all these systems are connected with each other and communicate with the brain.
  • There is an increasing understanding that many chronic diseases relate to Inappropriate engagement of the immune system, starting in the gut.
  • When Prof. Mayer started in the field, the term “gut health” did not exist. Now it’s a ubiquitous term which has associations with wellbeing, acknowledging the gut has influence on many other body systems.
  • The associations between gut (microbiota) and brain health started with provocative animal experiments from Cork, Ireland, in which researchers manipulated the gut microbiome and found changes in emotion-like behaviors of animals. However, it has been difficult to translate to human interventions.
  • How do microbiome-targeted dietary interventions affect the brain? We do know the “Standard American Diet” (deficient in fiber) has changed the gut microbes in a way that compromises the production and maintenance of the gut barrier. 
  • There are many misconceptions about “leaky gut”, but basically contact between beneficial microbes and immune system sensors stimulate the immune system of the gut to low-grade inflammation. This can alter the tight junctions, making the gut more permeable, and ultimately this can affect the brain. Diet can affect the role of microbes in maintaining an effective gut barrier.
  • Prof. Mayer describes how he ended up studying the microbiota-gut-brain axis – he would not have predicted how important and popular this field would become.
  • In the future, there will be more sophisticated and personalized interventions. He sees a paradigm shift happening from reductionist approaches in medicine to systems biological approaches. This field is making us acknowledge that diet will play a major role.

Episode links:

About Prof. Emeran Mayer MD:

Emeran A Mayer is a Gastroenterologist, Neuroscientist and Distinguished Research Professor in the Department of Medicine at the David Geffen School of Medicine at UCLA, the Executive Director of the G. Oppenheimer Center for Neurobiology of Stress & Resilience and Founding Director of the Goodman Luskin Microbiome Center at UCLA. He is one of the pioneers and leading researchers in the bidirectional communication within the brain gut microbiome system with wide-ranging applications in intestinal and brain disorders. He has published 415 scientific papers, co edited 3 books and has an h-index of 125. He published the best selling books The Mind Gut Connection in 2016, the Gut Immune Connection in June 2021, and the recipe book Interconnected Plates in 2023. He is currently working on a MasterClass and a PBS documentary about the mind gut immune connection. He is the recipient of numerous awards, including the 2016 David McLean award from the American Psychosomatic Society and the 2017 Ismar Boas Medal from the German Society of Gastroenterology and Metabolic Disease.

How the maternal microbiome influences offspring neurodevelopment, with Dr. Eldin Jašarević PhD

This episode features Dr. Eldin Jašarević PhD from University of Pittsburgh discussing research that investigates how maternal signals influence the general development and neurodevelopment of the offspring. Dr. Jašarević’s particular interest in this field stems from his family’s journey as refugees from Bosnia who found their way to the US. His lab studies how maternal stress or diet signals the developing brain to facilitate a lasting change, focusing on the role of the gut and vaginal microbiomes. His work in mouse models has shown that even mild stressors early in pregnancy trigger a gut microbiome change that lasts, but the challenge is to figure out whether the microbiome is responsible for the lasting effect. More human intervention studies are needed to understand how these findings may benefit pregnant women and the eventual development of their children. Regarding brain development, germ-free mice have brains that grow and develop differently from mice with an intact microbiome: for example, microbial metabolites are involved in key epigenetic processes for the brain. In general, the field may be moving toward understanding host-microbial interactions and dispersal of microbial-derived metabolites in pre-conception health and fertility, to eventually enable earlier intervention.

Episode abbreviations and links:

About Dr. Eldin Jašarević PhD:

Eldin Jašarević is an Assistant Professor in the Departments of Obstetrics, Gynecology and Reproductive Sciences and Computational and Systems Biology at the University of Pittsburgh, and a Principal Investigator at Magee-Womens Research Institute. He received his Ph.D. in Neuroscience from the University of Missouri, where he worked at the Thompson Center for Autism and Neurodevelopmental Disorders. His predoctoral research focused on the role of maternal lifetime experiences on brain development. During his postdoctoral fellowship with Dr. Tracy Bale at the University of Pennsylvania, Eldin defined mechanisms by which disease susceptibility can be transferred across generations via the microbiome. His current research focuses on understanding how microbial-derived signals act as regulators of development, with particular emphasis on the germline. His contributions to the field have been recognized through his selection as a Kavli Fellow of the National Academy of Sciences, a Burroughs Wellcome Fellow, and through research funding from NIMH, NICHD, and NIDDK.

Fiber and short-chain fatty acids for cognitive health, with Dr. Boushra Dalile PhD

This episode features Dr. Boushra Dalile PhD from KU Leuven in Belgium – ISAPP’s 2024 Glenn Gibson Early Career Researcher Award winner – discussing the protective role of fiber and prebiotics on cognitive health. Dr. Dalile is trained in psychology, and in her current work she undertakes human intervention studies to examine the effects of interventions using fibers, prebiotic fibers, and / or short-chain fatty acids on human stress- and anxiety- related processes. Fermentable fibers in the diet are known to result in the production of short-chain fatty acids (SCFAs), and she has been involved in studies in which participants receive the SCFAs directly. Interestingly, sufficient SCFAs circulating in the blood are required for protection against a stressor, regardless of any intervention. Dr. Dalile explains that cognitive deterioration may start 20 to 30 years before the first symptoms occur in later life, so that prevention (or “cognitive resilience”) is the most promising strategy. So far, the best recommendation is to maintain a fiber-rich diet throughout adulthood, although various research groups are working to find out whether a specific intervention could be effective for protecting cognition. This episode is the first of a series on the microbiota-gut-brain axis.

Episode abbreviations and links:

Additional resources:

ISAPP blog post: Can we estimate prebiotic effects from short-chain fatty acid production?

About Dr. Boushra Dalile PhD:

Dr. Boushra Dalile PhD is a Postdoctoral Researcher at the Laboratory of Biological Psychology at KU Leuven, Belgium. She was trained in psychology (Swinburne University of Technology, Australia) and cognitive neuroscience (University of Skövde, Sweden; The Max Planck Institute for Human Cognitive and Brain Sciences, Germany), before being awarded a PhD in Biomedical Sciences in 2021 at the Translational Research Center for Gastrointestinal Disorders at KU Leuven under supervision of Prof. Kristin Verbeke. Since her PhD, she investigates the effects of dietary fiber and the role of short-chain fatty acids (SCFAs) on stress and anxiety, and is currently mapping out their putative mechanisms of action in humans. Her latest research seeks to harness butyrate’s neuro-psychopharmacological potential in modulating learning and memory to advance translational research on anxiety and help shape treatment options and dietary recommendations. Her work was published in Nature Reviews Gastroenterology & Hepatology, The Lancet Planetary Health, Neuropsychopharmacology, and Psychoneuroendocrinology.

Archive Highlight: Biotics in animal and human nutrition, with Prof. Kelly Swanson PhD

 

Completing our series on the role of biotics in animal health, we are highlighting Episode 22 from our archives. In this episode, Prof. Kelly Swanson PhD from University of Illinois at Urbana-Champaign discusses the role of biotics in animal and human nutrition. He reviews the criteria for prebiotics and synbiotics, then discusses how we gain knowledge about nutrition and the role of biotics in animals compared to humans.

Key topics from this episode:

  • A good argument can be made that biotics are essential for our diet; they are beneficial even if efficacy is sometimes difficult to prove.
  • Nutrients have an impact on the host’s health and simultaneously on the host-associated microbes.
  • Health benefits are essential to the FDA definition of fiber.
  • Antibiotics’ effect on the microbiota: short-term effects may be minor, but we still don’t know the long-term effects.
  • The synbiotics definition, criteria for products to meet this definition, and the health outcomes from using these biotic substances.
  • The difference between complementary and synergistic synbiotics.
  • When studying biotics in companion animals (cats and dogs), can results from one host be extrapolated to another host? Final studies should be in the target host.
  • Biotics are important in veterinary medicine and a popular topic of study.
  • Predictions about the future of nutrition science as informed by the microbiome.

Episode links:

Additional resources:

About Prof. Kelly Swanson:

Kelly Swanson is the Kraft Heinz Company Endowed Professor in Human Nutrition at the University of Illinois at Urbana-Champaign. His laboratory studies the effects of nutritional interventions, identifying how diet impacts host physiology and gut microbiota. His lab’s primary emphasis is on gastrointestinal health and obesity in dogs, cats, and humans. Much of his work has focused on dietary fibers and ‘biotics’. Kelly has trained over 40 graduate students and postdocs, published over 235 peer-reviewed manuscripts, and given over 150 invited lectures at scientific conferences. He is an active instructor, teaching 3-4 nutrition courses annually, and has been named to the university’s ‘List of Teachers Ranked as Excellent by Their Students’ 30 times. He serves on advisory boards for many companies in the human and pet food industries and non-profit organizations, including the Institute for the Advancement of Food and Nutrition Sciences and International Scientific Association for Probiotics and Prebiotics.

Developing probiotics to prevent white nose syndrome in bats, with Prof. Ann Cheeptham PhD

This episode features Prof. Naowarat (Ann) Cheeptham, a cave microbiologist from Thompson Rivers University (Canada), speaking about a fungal infection in bats that causes white nose syndrome. She and her collaborators are looking at the microbiomes of the bats and their environments for possible ways to prevent this serious infection. White nose syndrome is caused by Pseudogymnoascus destructans infecting bats in hibernation and causing them to act in unnatural ways. The condition has caused massive death of bats in North America, although not in other regions of the world with the same fungus. Dr. Cheeptham and colleagues are looking for strategies to prevent white nose syndrome. Initially they screened environmental bacteria with activity against the fungus, but had difficulty knowing how to apply these bacteria to the bats. Their current approach is to take four bacterial strains isolated from healthy bats and apply them in bat boxes so they may become established on the vulnerable bats to prevent white nose syndrome. The preventative actions of the bacteria are still under investigation, but the collaborators believe the mechanism is related to metabolite production. This episode is part of a series on the role of biotics in animal health.

Episode abbreviations and links:

About Prof. Ann Cheeptham PhD:

Dr. Cheeptham is a professor at the Department of Biological Sciences, Thompson Rivers University, Kamloops, British Columbia, Canada. Her research interests include cave microbiomes/new drug discovery, white-nose syndrome in bats, alternative treatment tools against multidrug-resistant infections, and geomicrobiology.  Her work has fortunately been featured in the New York Times, WIRED, Bloomberg TV network’s Spark series, Al Jazeera TV, the CBC’s Nature of Things (The Antibiotic Hunters episode), Global TV (Global 16×9 and Global Health), Knowledge Network, CBC radio (Daybreak) and in several International and Canadian magazines.  Besides her passion for cave microbiology and research, she is also drawn to pedagogical issues in microbiology education. Recently, she has been the recipient of the 2022 3M National Teaching Fellowship from the Society for Teaching and Learning in Higher Education (STLHE) and 3M, the 2020 TRU Faculty Excellence Award, and the 2020 D2L Innovation Award in Teaching and Learning STLHE and D2L (Desire2Learn).

Targeting the rumen microbiota for reduced methane production, with Prof. Alex Hristov PhD

This episode features Prof. Alex Hristov PhD from Penn State University (USA) talking about the microbiota of ruminants and how it can be targeted for reduced methane production. The rumen (pre-stomach area) of cows and other animals contains microorganisms that digest the feed before it enters the rest of the gastrointestinal tract. Hydrogen is produced to inhibit further fermentation of the feed, and this hydrogen is rapidly converted to enteric methane, which is emitted by the animal – accounting for a large proportion of methane emissions that contribute to global warming. Several approaches exist for targeting the rumen microbiota with the aim of reducing methane emissions. Some feed additives, including one recently approved by regulators in the US, can reduce enteric methane by around 30% and appear safe for the animal. Vaccines against the methane-producing archaea in the rumen are another potential approach suitable for grazing livestock. Direct microbials have also been advanced. Many other sources of methane emissions exist besides livestock, but significantly reducing the methane production in the livestock industry could have a major positive impact on global warming. Feed additives for now are the leading strategy, and adoption of existing solutions in multiple places is critical. This episode is part of a series on the role of biotics in animal health.

Episode abbreviations and links:

Additional resources:

ISAPP blog post: Microbiota from a surprising source—baby kangaroos—might decrease cattle methane production

About Prof. Alex Hristov PhD:

Dr. Alexander N. Hristov is a Distinguished Professor of Dairy Nutrition in the Department of Animal Science at The Pennsylvania State University. He has a Ph.D. in Animal Nutrition from his native Bulgaria. Hristov has worked at the USDA-ARS Dairy Forage Research Center in Madison, WI, the Ag Canada Research Center in Lethbridge, AB, was on the faculty at the Department of Animal and Veterinary Science, University of Idaho from 1999 to 2008 and is at Penn State since 2008. Hristov’s main research interests are in the areas of mitigation of nutrient losses and gaseous emissions from dairy operations and protein and amino acid nutrition of dairy cattle. He has published over 220 peer-reviewed journal papers, books, and book chapters.

Archive Highlight: Prebiotics for animal health, with Prof. George Fahey

Continuing our series on the role of biotics in animal health, we are highlighting Episode 5 from our archives. This episode features a former ISAPP board member, Prof. George Fahey, giving an overview of animal prebiotic research and describing future opportunities for prebiotics in animal nutrition. Prof. George Fahey is a prominent animal nutrition scientist who is currently Professor Emeritus at University of Illinois. Fahey explains how animal nutrition research relates to human nutrition research, and the changes in the field he has seen over the course of his long career. He describes the research on prebiotics for animal nutrition, covering both livestock and companion animals.

Key topics from this episode:

  • A short history of animal prebiotics research as well as future opportunities in animal nutrition.
  • Pro- and prebiotics are being explored as an alternative to antibiotic treatment in production animals. Antibiotics are overused, leading to an increase in antibiotic resistance; the “biotics” therefore have great potential in animal nutrition.
  • Probiotics can potentially be used instead of antibiotics to inhibit pathogens and support the gut microbiota in animals.
  • Prebiotics possibly have high nutritional value and beneficial effects in animals, especially in poultry and pigs.
  • There are limitations to using prebiotics in the animal industry, especially for some animals such as horses and ruminants.
  • There has been increased use of prebiotics for companion animals (pets) in the past few years. Now many pet foods contain prebiotics.
  • Benefits of using prebiotics in companion animals:
    •  Support digestive health
    •  Improve stool quality
    • Support the gut microbiota, which also translates to good stool quality
  • A short overview of how companion animals’ food is produced, and the timing of adding prebiotics.
  • Wild animals’ diet has low nutrition with limited to no prebiotic intake, resulting in a shorter lifespan in comparison with companion animals
  • Some take-home points from animal models and animal nutrition research.

 

Episode links:

Expert consensus document: The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of prebiotics
The International Scientific Association for Probiotics and Prebiotics consensus statement on the scope and appropriate use of the term probiotic

 

Additional resources:

Are prebiotics good for dogs and cats? An animal gut health expert explains. ISAPP blog post
Using probiotics to support digestive health for dogs. ISAPP blog post
Prebiotics. ISAPP infographic

 

About Prof. George Fahey:

George C. Fahey, Jr. is Professor Emeritus of Animal Sciences and Nutritional Sciences at the University of Illinois at Urbana-Champaign. He served on the faculty since 1976 and held research, teaching, and administrative appointments. His research was in the area of carbohydrate nutrition of animals and humans. He published numerous books, book chapters, journal articles, and research abstracts.

He currently serves on two editorial boards, numerous GRAS expert panels, and is scientific advisor to both industry and governmental organizations. He retired from the University in 2010 but continues to serve on graduate student committees and departmental search committees. He owns Fahey Nutrition Consulting, Inc. that provides services to the human and pet food industries.