News Archive

Gordon Conference on lactic acid bacteria

The first ever Gordon Research Conference on lactic acid bacteria was held in Ventura, CA from July 23 to 28, 2023. The conference was a fun week of interactive sessions and lots of time for networking and making new friends pursuing research on this fascinating group of bacteria. We had over 120 participants from nearly all corners of the world. The meeting included excellent speakers and impressive posters on a wide-range of topics including lactic acid bacteria metabolism, cell surface composition, and phages, to fermented foods and uses of these bacteria in medicine and engineering.

Be on the lookout for the next meeting expected in 2025!


New paper on the benefits of friendly microbes in our diets

Our collaborative ISAPP group found that foods with higher microbial concentrations are associated with modest health improvements across a range of outcomes. This paper used NHANES participants’ reported food intake to quantify the food they ate that contained medium or high levels of microbes. Then they determined how these intakes correlated with various markers of health such as blood pressure and weight. We found that increased consumption of live microbes in the diet was linked with multiple measurements of better health: more favorable blood pressure, better blood glucose and insulin, lower inflammation, as well as lower waist circumference and body mass index. This established that those who consumed higher quantities of live dietary microbes showed tangible, if modest, health benefits.

New paper on intraspecific diversity of L. plantarum

This published in Applied Environmental Microbiology shows how intraspecies interactions in food fermentations are dependent on metal cation availabilty. We are excited to share these findings because they provide new insight on the ecological interactions and nutritional requirements of microbes in food fermentations which can be used to improve the quality and consistency of those foods.

Glory Bui wins ISAPP SFA poster award

Glory Bui (PhD student MGG) received the honor of a coveted poster award at the annual International Scientific Association of Probiotics and Prebiotics (ISAPP) meeting in Sitges, Spain. The award was given to two students by the Student Fellows Association (SFA). Congratulations to Glory on her excellent research and presentation on diffusible factors made by L. casei in milk which improve intestinal epithelial barrier function.

New project to prevent the spread of antimicrobial resistance

We are excited to share the news that we are launching a new project to reduce antibiotic use and risk of antimicrobial resistance in pig production. This $21.2 million, 5-year PIG-PARADIGM project is funded by the Novo Nordisk Foundation. Our lab is teaming up with other researchers at UC Davis and at universities in Denmark and the Netherlands. We will be studying how to prevent the need for antibiotics during pig weaning by improving digestive tract resilience through the gut microbiome. More information about our plans can be found here and here.

Congratulations to Ruchita on the completion of her MS research

We are excited to share the news that Ruchita Uttarwar completed her MS research and graduated this June. Her thesis is titled "Effect of amoxicillin clavulanate on the intestinal microbiota and metabolomes of mice administered yogurt and Bifidobacterium animalis subsp. lactis BB-12". We are thrilled for her upcoming manuscript and bright future ahead.

Congratulations to Eric Stevens PhD

Congratulations to Dr. Eric Stevens on the completion of his dissertation research. Eric's studies have shed new light on extracellular electron transfer metabolism performed by lactic acid bacteria in food fermentations.

Lactobacilli make electricity?

Eric Stevens' dissertation research has led to exciting new findings on the metabolism of lactic acid bacteria. Through his research and together with our collaborators at Rice University, we discovered how L. plantarum uses extracellular electron transfer to improve growth and acidify its environment. Read more about our findings here at eLife and the UC Davis press release.

How different dietary fibers affect the gut microbiome

Congratulations to Zach Bendiks on his Journal of Functional Foods paper investigating how the gut microbiome changes in response to different dietary fibers. Resistant starch is highly selective and increases expression of stress-response genes corresponding with reductions in intestinal pH.

Research on the food and gut microbiome with indigenous peoples

Our perspective article on Inuit fermented foods is published in the new journal Microbiome Research Reports. This article provides guidance on how to approach microbiological research questions on Inuit fermented foods so that it centers Inuit knowledge within the specific geographic, social, and cultural contexts in which these foods are made. 

New project to understand yogurt digestion

We are excited to be embarking on a new project funded by the California Dairy Research Foundation and the National Dairy Council to compare yogurt and plant-based yogurt products for their digestibilty and delivery of probiotic bacteria to the digestive tract. This project is being conducted together with Professor Gail Bornhorst (FST and BAE, UC Davis). We hope to begin to understand the similarities and differences in how the nutrients and microbes in these foods are made bio-available during digestion in the stomach and small intestine.

August 2021

Our paper on the development of a molecular diagnostic multiplex qPCR assay for detection of Mycoplasma species in milk as important causes of contagious mastitis in dairy cattle is now published in PeerJ. This article was made possible by a grant from the California Dairy Research Foundation and our amazing collaborators Drs. Aly and Lehenbauer in the UC Davis School of Veterinary Medicine.

June 2021

Congratulations to Zach Bendiks for receiving the UC Davis 2021 Kinsella Memorial Prize. This award, established in honor of late Dean and Professor John E. Kinsella, is awarded to the best dissertation based on the quality and originality of the work, the multidisciplinary impact of the research, and the importance of the research to the College of Agricultural and Environmental Sciences (CA&ES) mission to serve agriculture, the environment, and human health and development.

June 2021

We are excited about our new publication on the diversity of Lactiplantibacillus plantarum isolated from plants and plant foods. This paper gives insight into the ecological strategies of L. plantarum and how it as adapted to different plant types and fermented foods and was made possible by funding from the USDA National Institute of Food and Agriculture.

February 2021

Check out our new publication on the microbiota in Cheddar cheese and research which led us to identify the microorganisms responsible for slit defects. This work was made possible by the California Dairy Research Foundation. 10.1128/mSystems.01114-20

January 2021

The ISAPP consensus paper on fermented foods is now published. The paper provides a new definition of fermented foods and beverages and provides guidance on the difference between probiotics and fermented foods. For more information - see Maria's blog and this summary.

November 2020

Maria's "Crystal Ball" article was published in Microbial Biotechnology. The article proposes that research defining the precise ways microorganisms benefit human health will be expanding rapidly in the near future. For more reading about this article, see here.

October 2020

For more information on our EATLAC community science project, see our website here:

July 2020

Congratulations to Dr. Annabelle Yu for completing her dissertation research on the intra-species diversity of plant-associated lactic acid bacteria!

May 2020

Our comprehensive review on how the gut microbiome changes in response to resistant starch type 2 was published in Nutrition Research. Congrats to Zach on leading the way on this paper!

February 2020

We published a review on probiotic prevention of antibiotic associated diarrhea (AAD). The crux is that we still know very little about AAD and the molecular mechanisms responsible for probiotic effects.

December 2019

Congratulations to Zach for winning a poster prize at the 2019 Stanford Microbiome Symposium!

November 2019

Our paper showing that Lactobacillus plantarum rapidly repairs epithelial barriers in the virally inflammed gut by a PPARalpha derived mechanism was published in the Proceedings of the National Academy of Sciences.

October 2019

Congrats to Annabelle on her review on the abundance, diversity, and plant-specific adaptations of plant-associated lactic acid bacteria published in Environmental Microbiology Reports.

October 2019

We were awarded a new two-year grant to develop educational resources and research on fresh fermented fruits and vegetables from the California Department of Food & Agriculture.

July 2019

Maria joined the Kerry Health & Nutrition Institute's Scientific Advisory Council.

April 2019

Our paper showing how the bacterial composition in milk changes dramatically over the course of a day at each processing step was published in Applied Environmental Microbiology.

March 2019

Our paper on the identification of the bacterial receptor for the bacteriocin Plantaricin EF was published. This paper shows how the bacteriocin targets metal homeostasis in bacterial cells.

February 2019

Maria joined the International Scientific Association for Probiotics and Prebiotics (ISAPP) Board of Directors.

January 2019

We published a paper describing rapid assays to detect Mycoplasma bovis, an important bovine mastitis causing pathogen, in the Journal of Dairy Science. This work was brought about by our collaboration with Drs. Sharif Aly and Terry Lehenbauer in the UCD School of. Veterinary Medicine and with support from the California Dairy Resarch Foundation. 

​January 2019

Our studies on how milk and milk fermented by Lactobacillus casei  can prevent impairments to intestinal epithelial barrier integrity in Caco-2 cells was published this month in the Journal of Agricultural and Food Chemistry.

November 2018

Our paper showing that L. plantarum iconsumption results in reduced weight gain and the barrier-protective properties of of the L.plantarum bacteriocin plantaricin EF was published in Gut Microbes

November 2018

Congratulations to Zeya on being awarded second place in the oral competition at Jiangnan University's Global Food Science Student Competition. She was one of 70 students competing from 60 Universities, representing 36 countries.

October 2018

Our paper "Microbiota, metabolome, and immune alterations in obese mice fed a high-fat diet containing type 2 resistant starch", published in Molecular Nutrition & Food Research, was one of the journal’s top 20 most downloaded recent papers in the past year

October 2018

Our paper on how DNA sequencing and bioinformatics methods impact bacterial community analysis was published in mSphere.

October 2018

Maria joined The Fermentation Association Advisory Board

May 2018

Ellie's paper on the role of sucrose metabolism for Lactobacillus plantarum in the digestive tract was published in FEMS Microbiology Ecology

April 2018

Congratulations to Eric Stevens on being selected for a National Science Foundation Graduate Research Fellowship award

April 2018

Congratulations to Ellie Yin on being selected for the John E. Kinsella Memorial Prize for outstanding research on her doctoral dissertation

April 2018

Zach Quart and Hiu Mak presented their research at the UC Davis Undergraduate Research Conference. Well-done to two of our excellent undergraduate students!

March 2018

Congratulations to Annabelle Yu on being selected to travel to Uganda this summer as part of a Trellis Fund Project from the Feed the Future Innovation Lab for Horticulture

February 2018

Maria was the guest editor on this year's Current Opinion in Biotechnology, Food Biotechnology issue

November 2017

Ellie's paper on the importance of Lactobacillus plantarum plantaricin synthesis in the GI tract was published

October 2017

Our review on intestinal Lactobacillus and its association with health and disease was published in Current Opinion of Biotechnology. (

October 2017

Congratulations to Eric Stevens on his Science Communications Fellowship from the Sacramento Powerhouse Science Center!

September 2017

Ellie Yin's research on how dietary and intestinal Lactobacillus respond to dietary changes is now published in Scientific Reports:

September 2017

Ben's paper describing a novel NRPS/PKS system in Lactococcus lactis is published in Microbiology Open  (​)

September 2017

Congrats to our ADA project team, and specifically to Javad, for our new comprehensive paper on dietary resistant starch and effects of RS type 2 on the gut and systemic health during consumption of a high fat diet. Journal of Molecular Food & Nutrition Research. (

June 2017

Our lab's work on milk and dairy products was featured on the UC Davis One Health Blog

January 2017

Both Elissa Goldman and Patricia Matus are recipients of the UC Davis Provost's Undergraduate Fellowships.

September 2017

Ellie's paper on Lactobacillus delbrueckii ssp. bulgaricus milk- and low-temperature-associated proteomes was published in mSystems. This paper is a result of our collaboration with Drs. Velitchka Gotcheva and Angel Angelov at the University of Food Technologies, Bulgaria. (

December 2016

Check out our new review article on the health benefits of fermented foods:

November 2016

Casper Jamin, an MS student from Wageningen University, joined our lab for a six-month internship.

December 2016

Koen Askamp,  an MS student from Wageningen University, joined our lab for a six-month internship.

November 2016

Ya-Yun (Jenny) Wang, a PhD student from the National Chung Hsing University, joined the lab for a year long internship.

October 2016

New publication in Frontiers in Microbiology on comparisons of fecal processing methods for metagenomics analyses:

August 2016

New publication on the bacterial composition in raw milk in tanker trucks and silos at CA dairy processors. This article has a press release and has been covered by a number of news media sources:

August 2016

ASM Microbe Magazine feature article on Fermented Foods:

June 2016

Congratulations to Dustin for his poster award at the ISAPP meeting in Turku, Finland!

June 2016

Nathan Lee and Kane Tian join our lab for the UCD Young Scholar's Program (YSP). Nate and Lee are impressive high school students here to take classes and perform research for 6 weeks this summer. 

May 2016

The lab welcomes Dr. Kanika Chauhan, a new postdoctoral scholar, to the lab. She will be studying pathogens that cause bovine mastitis.

May 2016

Welcome to Natalia Ribeiro, an undergraduate student from the University of Campinas, Brazil. She will be performing a summer internship in our lab through a Science Without Borders Scholarship program.

April 2016

New publication in Scientific Reports on the transcriptome of Lactobacillus plantarum and the indigenous bacteria in the small intestine. Congrats to Ben for his lead authorship on this paper-
For more information, see the press release on the paper:

April 2016

Ben Golomb was awarded the Max Kleiber Thesis Research Prize. Congratulations to Ben on this impressive honor.

April 2016

Zeya wins the IFT Feeding Tomorrow Graduate Scholarship. Way to go Zeya! 

March 2016

Congratulations to Zeya for her admittance into the Food Science Graduate Group PhD program.

March 2016

Dustin was awarded a prestigious NSF Research Fellowship award. Way to go, Dustin!

February 2016

Congratulations to Ben Golomb for completing his PhD on the adaptations of Lactococcus lactis and Lactobacillus plantarum to their hosts. We wish you much success at your new job!

February 2016

Check out Dorothy Kieffer's new paper on resistant starch amelioration of chronic kidney disease and effects on the gut microbiota and metabolome just published in The AMJ Renal Physiology ( UPDATE (April 2016) This paper was selected by the American Physiological Society to be recognized as among the best recently published articles in physiological research!

February 2016

New paper in Frontiers in Microbiology ( on the limitations of using PMA and RNA to quantify viable bacterial cells on plants. This paper was featured on the Barfblog (

February 2016

New paper in Journal of Applied Microbiology (  This paper details our investigations on the metabolic capacities of Lactobacillus florum and specifically the production of erythritol and mannitol. Congrats to Charlotte on her dedication to this project!

November 2015

Dr. Zhengyuan Zhai has joined our group. Dr. Zhai joins us from the China Agricultural University and has a fellowship from the China Postdoctoral Science Foundation (CPSF).

July 2015

Two new publications from our lab on probiotic - dairy connections for health benefits:

June 2015

Pujita Munnagni, a very talented high school student, joins our lab through the UC Davis Young Scholar's Program ( Welcome Pujita!

April 2015

The USDA announced our new NIFA AFRI grant in the Food Quality program: 
With this grant, we will investigate plant-associated lactic acid bacteria for novel functional traits relevant to food processing and human health. We will employ genetic and functional screening methods to better understand these bacteria in plant-based foods.

March 2015

Irene Yim, a McNair Scholar, joins the lab to perform her undergraduate research. Welcome Irene!

December 2014

Bokyung Lee completed her PhD in Food Science. Her studies have shown the significant impact that the food delivery matrix has on probiotic efficacy in the digestive tract. Congratulations Bokyung!

November 2014

Wentin Ju (postdoc) accepted a position at Mérieux NutriSciences. He will be working on food safety programs closer to home in China. Congratulations Wenting!

November 2014

Ben Golomb's paper was published in the Journal of Bacteriology on the transcriptome and metabolome of Lactococcus lactis KF147 during growth on plant tissues.

October 2014

Commentary published in the ASM monthly magazine Microbe on the contributions of Herbert Conn to microbiology. This paper was the result of an ASM Milestones in Microbiology at the University of Connecticut event to honor this pioneer in dairy microbiology in the USA.

September 2014

Galya Blagoeva returns to the lab as a USDA FAS Borlaug Fellow. Galya's 3 month project is to investigate the unique properties of starch-degrading lactic acid bacteria. Her work here is an extension of her PhD thesis project at the UFT, Bulgaria.

August 2014

Paper published in mBio showing how it is possible to transplant microbial communities from one plant to another. This technique is useful for dissecting microbial community interactions in the phyllosphere.

August 2014

Charlotte Tyler completed her MS degree. Charlotte studied the metabolism of plant-associated lactic acid bacteria and the function of yeasts and bacteria in olive fermentations. We will miss you Charlotte!

April 2014

The lab welcomes Galya Blagoeva from the University of Food Technologies, Bulgaria for a PhD fellowship visit

March 2014

Paper published in the Annuals of the New York Academy of Science on factors influencing probiotic efficacy and guidelines for evaluating probiotic safety and efficacy.

February 2014

Xiaochen Yin's paper on the effects of dairy and probiotic consumption on the indigenous intestinal microbiota was published in the Journal of Dairy Science. Consistent but non-overlapping effects were found with the ingestion of Lactobacillus casei and milk.

January 2014

Lauren Kopit and Eun Bae Kim's examination of the safety of Enterococcus faecium NRRL B-2354 was published in Applied Environmental Microbiology. Using a combined genomics and phenotyping approach, we confirmed the suitability of this strain for use as a surrogate organism in place of Salmonella in tests of thermal processing procedures for food products.

October 2013

Eun Bae Kim's paper on Enterococcus faecium and Enterococcus faecalis comparative genomics was published in Applied Environmental Microbiology. This paper shows that community (non-clinical) strains of E. faecium but not E. faecalis have different genomic features from clinical (hospital-associated) strains.

October 2013

Congratulations to Tom Williams for winning first place in the Robert Mondavi Institute graduate poster prize. His poster was selected out of 14 entries. Well done Tom!

September 2013

Congratulations to Eun Bae on his new job as a faculty member at the Department of Animal Products and Food Science, College of Animal Life Sciences, Kangwon National University, Republic of Korea

September 2013

Sybille Tachon's paper was published in Environmental Microbiology. This paper provides compelling evidence that probiotics can be more or less effective depending on the diet consumed by the host. Probiotic Lactobacillus survived in higher numbers in the digestive tract and was more protective against intestinal inflammation in mice consuming a high-fat, high-sugar diet.

August 2013

New publication on the detection of viable E. coli O157:H7 on field and growth chamber lettuce:
Assessments of total and viable Escherichia coli O157:H7 on field and laboratory grown lettuce
Moyne, Harris, and Marco in PLoSOne. e70643

August 2013

Congratulations to Yelizaveta (Liza) Luchkovska on her award of the Provost's Undergraduate Fellowship! She will use the funds she received in this award to support her investigations on the microbial diversity of olive fermentations.

July 2013

Congratulations to Lauren! Lauren Kopit won 3rd place in developing scientist competition at the International Association of Food Protection meeting held in Charlotte, North Carolina, July 29-Aug 1. She presented her work on the surrogate strain Enterococcus faecium NRRL B-2354.
She also recently received her MS in Viticulture and Enology and is the first to graduate from the lab. We will miss you Lauren

July 2013

New publication on the microbiota in the lettuce phyllosphere:
Season, irrigation, leaf age, and Escherichia coli inoculation influence the bacterial diversity in the lettuce phyllosphere. by Williams, Moyne, Harris, and Marco in PLoSOne. e68642

June 2013

Our lab was featured in the journal International Innovation  (see publications page)

May 2013

Congratulations to Xiaochen (Ellie) Yin on her publication in The Journal of Immunology ( The
study, led by the group of Richard A Flavell (Yale University) shows the role of  IL-22 in shaping the intestinal microbiota and the transmissible susceptibility to inflammatory colitis due to altered microbiota in IL-22-deficient mice. Ellie performed the gut microbiota analyses in this study. The paper was also highlighted by the journal (

May 2013

Kick-off on our new project "Bacterial signatures of milk quality" sponsored by the California Dairy Research Foundation. See here for the interview and press release:

April 2013

Congratulations to Tom Williams! He won both the Chancellor's Grand prize and the Dean's prize in the College of Agriculture and Environmental Science for his oral presentation at the UC Davis Interdisciplinary Graduate Symposium (
Way to go Tom!

January 2013

Eun Bae Kim is the first author on a paper describing the first genome sequence of Lactobacillus florum

October 2012

Check out our new publication on fermented olives and pectinolytic yeast from olives associated with spoilage in Food Microbiology.

October 2012

Lauren Kopit won 2nd place in the annual RMI graduate student poster competition for her poster entitled "Evaluation of the safety of Enterococcus faecium NRRL B-2354 used in thermal process validation". Lauren is a 2nd year MS student in V&E. Her project is funded by the Almond Board of California. Congratulations Lauren!

October 2012

The genome announcement for Enterococcus faecalis ATCC29212 was just published in the Journal of Bacteriology.

October 2012

Review article by Sybille Tachon and Maria entitled "Environmental factors influencing the efficacy of probiotic bacteria" was published in the Current Opinion in Biotechnology.

September 2012

Visit from Roland Siezen and Lex Overmars from Nijmegen University to develop our collaboration on enterococcal genomes

August 2012

The Marco lab has a new collaboration to investigate Lactobacillus bulgaricus together with faculty at the University of Food Technologies, Plovdiv, Bulgaria through the America Bulgaria Foundation

August 2012

Probiotics for cleaning countertops?  See article published in the Bay Area News Group.

August 2012

New lab publication on how the intestinal microbiota in aged mice is modified by the consumption of dietary resistant starch and correlated to improvements in host feeding responses, weight, and production of proglucagon. Tachon et al in FEMS Microbiology Ecology. In press.

July 2012

The Scientist highlights probiotics and Maria and the Marco lab is cited. :

July 2012

The Marco lab was awarded funds through the UC Davis RISE grant program. The grant is for 3 years of support to develop new RNA-Based, Amplification Free, Pathogen Identification methods Using Nano-Enabled Electronic Detection (RAPID-NEED).

June 2012

Maria was nominated for a  2012 ASUCD Excellence in Education Award. This award is completely student-funded, student-nominated, and student-chosen. Maria sends her thanks to the students in FST104 for the nomination. It is an amazing honor and such an amazing award considering that Food Microbiology is definitely not an easy A!

May 2012

 Tom Williams is featured by the UC Davis Office of Graduate Studies

April 2012

Maria was selected to be a Lecturer for the 2012-2014 American Society for Microbiology Branch Lectureships (ASMBL) program.

March 2011

The Marcolab was featured in a KQED QUEST video on the making of Sourdough.