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

/in Podcast, Season Four /by Laura

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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

/in Podcast, Season Four /by Laura

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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

/in Podcast, Season Four /by Laura

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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

/in Podcast, Season Four /by Laura

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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

/in Podcast, Season Four /by Laura

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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

/in Podcast, Season Four /by Laura

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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

/in Podcast, Season Four /by Laura

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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

/in Podcast, Season Four /by Laura

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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 Podcast, Season Four /by Laura

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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

/in Podcast, Season Four /by Laura

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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

/in Podcast, Season Four /by Laura

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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 Podcast, Season Four /by Laura

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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.