Li and Ishaq labs receive NIH R15 award to study broccoli bioactives, gut microbes, and inflammation!

The Li and Ishaq labs at UMaine, along with collaborators from multiple institutions, have been awarded R15 funding from the National Institute Of Diabetes And Digestive And Kidney Diseases of the National Institutes of Health!

This award will complement other projects/awards led by our team, which has been investigating inflammatory bowel diseases, anti-inflammatories, gut microbes, and nutrition, separately for decades and collaboratively for over two years.

  • Dr. Yanyan Li, PhD (lead PI), Assistant Professor at the University of Maine with expertise in nutrition and food science, particularly dietary bioactives and colitis;
  • myself (co-PI), with expertise in host-associated microbiology, especially GI tract;
  • Dr. Grace Chen, MD, PhD (co-I), Associate Professor at the University of Michigan, expertise in mouse models for gut microbiome and colonic host immune responses;
  • Dr. Tao Zhang, PhD (consultant), Assistant professor at Binghamton University, with expertise in metabolism, kinetics, and bioanalysis of natural products;
  • Dr. Gary Mawe, PhD (consultant), Professor at the University of Vermont, with expertise in translational research on GI tract regulation, inflammation, and IBD;
  • Dr. Peter Moses, MD (consultant), Professor Emeritus at the University of Vermont College of Medicine and Senior Researcher at GSK, with expertise in IBD and functional gastrointestinal disorders.

R15 Research Enhancement Awards are designated for projects which involve a large number of student researchers. Between the Li and Ishaq labs, there are three current graduate students, and two former undergrads who have contributed to this research, and we anticipate bringing in 1-2 additional graduate students and almost a dozen undergrads in the next year! That will include undergrads in Honors, Top Scholars, and Capstone programs at UMaine. We’ve also been assisted by the work of students, postdocs, technicians, and investigators through our collaborators, and we are ecstatic about the opportunity to continue to grow our team across institutions. And, this project will generate research that will feed back into education at UMaine through the courses that we teach, such as my microbiomes and DNA sequence analysis courses.

“Harnessing gut microbiota to reduce inflammation using broccoli-sprout diets.”

Project Summary:

Inflammatory bowel disease (IBD) is a poorly understood gastrointestinal (GI) condition characterized by inflammation. The prevailing theory is that combined genetic and environmental factors disrupt the host immune system’s interaction with gut microbiota. Our central hypothesis is that consumption of specific broccoli sprout preparations elicits changes in the gut microbiota that not only improve the production of anti-inflammatory bioactives, but also promote intestinal homeostasis. Our labs have shown there is an anatomical pattern along the GI tract where broccoli sprout-derived bioactive levels are high which correspond to diet-induced changes in gut microbial communities. We showed that gut microbiota contribute to the transformation of inactive precursors to bioactives, and that specific broccoli sprout preparations alter their capacity for biotransformation, and the susceptibility of mice to colitis. However, a significant knowledge gap remains regarding the mechanisms by which dietary bioactives modify disease risk and the role of gut microbiota. Our immediate goal is to identify the mechanisms by which broccoli sprout diets affect susceptibility to IBD in mice. Our long-term goal is to develop a dietary preparation of
broccoli sprouts which has therapeutic effects against IBD in humans. Our innovative approach uses different preparations of broccoli sprouts to help differentiate gut microbiota versus plant-derived
enzymatic activities. We employ a combination of “omics” approaches to spatially-map the microbial community and metabolite profile changes along the GI tract, to better assess changes induced by broccoli sprout diets. We complement “omics” approaches with culturing, and validate our study design using two complementary models for strategic research.

A cartoon of three gastrointestinal tracts showing the locations of inflammation in ulcerative colitis, crohn's disease, or healthy tissue. At the bottom are cross-sections showing thickening of the intestinal wall in patients with Crohn's, and ulcers in patients with colitis.
Created by Johanna Holman.

Aim 1 tests the hypothesis of an anatomical pattern where the GI tract microbiota transform broccoli compounds into bioactives, and helps us determine whether this microbial biotransformation is sensitive to dose of broccoli compounds. We will use our established DSS-mouse-model of ulcerative colitis to investigate the effects of different broccoli sprout preparations and concentrations on the microbiota along the GI tract; on the resulting concentration of bioactives in gut tissues; and on the development of colitis in mice.

A cartoon schematic of the experimental design of the project. Four mice are at the top, two have "DSS" written above them, one of which is also holding a broccoli sprout. One of the mice without DSS written on it is holding a broccoli sprout. Below the mice is a cartoon of the digestive tract with arrows emanating from it to indicate samples of microbes will be taken from different locations. The microbe images have arrows pointing to culturing equipment, and also to a biochemical pathway showing the compound glucoraphanin being converted to sulforaphane.
Created by Sue Ishaq, made with Biorender

Aim 2 tests the benefits of using an immunosuppressed mouse model in the dietary prevention study to provide a stronger translational strategy for the use of broccoli sprouts for IBD prevention. When exposed to a specific bacterial pathogen, the immunosuppressed mice develop chronic enterocolitis resembling Crohn’s disease. This diet-based approach provides critical information for developing accessible and equitable strategies for improving health of IBD patients.

A cartoon schematic of the experimental design of the project. Two mice are at the top, with the label "IL-10" crossed out above them. One mouse is also holding a broccoli sprout.  Below the mice is a cartoon of the digestive tract with arrows emanating from it to indicate samples of microbes and tissue will be taken from different locations. The words weight and plasma indicate those will also be collected. The plasma and tissue samples will be used for mass-spectroscopy and histology, and the microbes will be used for DNA sequencing.
Created by Sue Ishaq, made with Biorender

Li and Ishaq labs receive Allen Foundation funding to research broccoli bioactives!

The Allen Foundation awarded Dr. Yanyan Li, Assistant Professor of Food Science and Human Nutrition, and myself funding for a pilot project in people on broccoli sprouts, the gut microbiome, anti inflammatory compounds, and health! Dr. Li and I, as well as a team of other researchers, have been collaborating over the last three years to understand how certain gut microbes create an anti-inflammatory compound using a compound in broccoli sprouts, and how we can use this action to calm colitis. Over the next 18 months, we will be recruiting a small group of people to participate in a diet trial. This will form the first part of the PhD work for Johanna Holman, who recently defended her master’s of science at UMaine.

Project Summary:

There is increasing evidence that diet and the gut microbiota have significant impact on human health and thus impact susceptibility to disease such as inflammatory bowel disease. Indeed, a Westernized diet has been associated with higher risk for developing inflammatory bowel disease, primarily as ulcerative colitis and Crohn’s disease, while a diet rich in fruits and vegetables tends to reduce risk. Our preliminary data suggests that a specific whole-food preparation of broccoli sprouts protects against the development of colitis in a chemically-induced mouse model as well as in a transgenic mouse model of Crohn’s disease. Furthermore, the gut microbiome contributes to the generation of the active anti-inflammatory component, sulforaphane, from broccoli sprouts, and the microbiome, in turn, is altered by exposure to broccoli sprouts or its metabolites. Thus, our long-term goal is to understand the interactions between anti-inflammatory bioactives of broccoli sprouts and the gut microbiome. The current proposal aims to increase our understanding of the nutrigenomics of the human microbiome and a broccoli sprout diet in healthy subjects. Our goal is to determine the feasibility of incorporating a specific broccoli sprout preparation into whole-food diets to increase levels of anti-inflammatory bioactives from broccoli sprouts in healthy humans. These directly address the foundation’s priority of “bringing the promise of nutrigenomics or nutritional genomics to realization”. Results from this study will help determine the feasibility and potential efficacy of a whole food approach in promoting intestinal homeostasis and mitigating risk of developing inflammatory bowel disease.

Diagram of the chemical conversion of glucoraphanin to sulforaphane. In panel A, the process is shown using the plant enzyme myrosinase, and in panel B, the process is shown using bacterial myrosinase-like enzymes. In the middle of the diagram, there is a cartoon mouse eating broccoli. Panel A points to the broccoli, where that action occurs, and panel B points to the gut, where microbial conversion occurs,
Figure from Holman et . in review, artwork by Johanna Holman. Glucoraphanin hydrolysis. A. GLR hydrolysis in the presence of myrosinase upon damage to the broccoli plant. Epithiospecifier protein preferentially converts GLR to SFN-nitrile. B. GLR hydrolysis has been demonstrated by gut bacteria in the colon of mammals.  Low pH environments favor conversion to SFN-nitrile.

Pilot project funded to study Vibrio bacteria in scallop farming

A collaborative pilot project was funded by the Maine Food and Agriculture Center (MFAC) to investigate Vibrio bacteria in scallop hatcheries in Maine! This will support some ongoing work by a collaborative research team at UMaine and the Downeast Institute, as we develop a long-term, larger-scale project investigating scallop health and survival in hatcheries, something which will be critical to supporting sustainable and economically viable aquaculture productions.

“Investigating microbial biofilms in Maine hatchery production of sea scallop, Placopecten magellanicus.”

Principal Investigator: Sue Ishaq


  • Dr. Tim Bowden, Associate Professor of Aquaculture, University of Maine
  • Dr. Jennifer Perry, Assistant Professor of Food Microbiology, University of Maine
  • Dr. Brian Beal, Professor of Marine Ecology, University of Maine at Machias; and Research Director/Professor, Downeast Institute
  • Dr. Erin Grey, Assistant Professor of Aquatic Genetics, University of Maine

Project Summary: Atlantic deep-sea scallops, Placopecten magellanicus, are an economically important species, generating up to $9 million in Maine alone. Despite their potential to the aquaculture industry, hatchery-based sea scallop production cannot rely on the generation of larvae to produce animals for harvest. In hatcheries, the last two weeks of the larval maturation phase is plagued by massive animal death, going from 60 million scallop larvae down to a handful of individuals in a span of 48 hours. This forces farmed scallop productions to rely on collection of wild scallop spat (juveniles), but wild population crashes, habitat quality, harvesting intensity, and warmer water temperatures threaten the sustainability and economic viability of this industry. The reasons for sea scallop larvae death remain unknown, but other cultured scallop species are known to suffer animal loss from bacterial infections, including from several bacterial species of  Vibrio and Aeromonas. At the Downeast Institute in Beals, Maine, biofilms appear on tank surfaces within 24 hours. Routine screening for the presence of Vibrio sp. in tanks at DEI reveals no obvious signs of colonies in scallop tanks. Preliminary culturing and genetic identification from these biofilms suggests a species of Pseudoalteromonas, known biofilm formers which outcompete or inhibit other microorganisms. Our goal is to investigate the dynamics of tank surface biofilms in bivalve aquaculture facilities. Our long-term goals are to understand microbial community assembly and animal health during scallop hatchery production, and to standardize management practices to enhance the success of cultured scallop production.  

Experimental design schematic for this project. Our objectives are to 1) Identify the microbial community members involved in tank biofilms, and if it is a repeated or novel community assembly, and 2) Test for biofilm antagonism in vitro, using competing microorganisms, chemical treatments, and environmental conditions. 
A close-up picture of petri dishes containing a light yellow film of microbes.

Rebecca received an undergraduate research award!

Rebecca French, an undergraduate researcher in Animal and Veterinary Science, is beginning her time in the Ishaq Lab with an auspicious start: she has been awarded a 2021 research award from the J. Franklin Witter Undergraduate Research Endowment Fund! The fund supports AVS undergraduate student involvement in faculty supervised research which involves the J. Franklin Witter Teaching & Research Center.

Rebecca’s project will involve zoonotic disease tracking in rodent populations that live near farms/human development versus those which live in more natural areas, and will take place at the Witter farm and a paired natural ecosystem. Her project is part of a larger collaboration between myself and a team of researchers, which was recently funded by the University of Maine, but which has not yet been announced (details soon).

Rebecca formally joined my research lab in February of this year, but I have had the pleasure of teaching her in my data analysis class since January, which will be a handy skillset later in the project. She also learn and perform microbial culturing, qPCR, Sanger sequencing, and even some animal trapping, handling, and identification; mammal physiology data collection and analysis.

Rebecca French

Undergraduate Researcher, Animal and Veterinary Sciences

Rebecca is an animal and veterinary science student with a concentration in pre-veterinary medicine. She joined the Ishaq lab team in 2021 as a part of her capstone project, which is focused on flying squirrels and mice that are carrying zoonotic pathogens into Maine.

DNA double helix with dollar signs as a nucleotide.


Today a large-scale federal grant proposal was submitted, bringing me to four proposals submitted so far in 2020 (and eight total in the 2019/2020 academic year)! I have one more that is planned for the end of May, and two more that may be submitted this summer depending on the disposition of my pending proposals. Each of these proposals takes weeks to months of planning, writing, and coordination between the research team. The proposal submitted today was 107 pages, and only some of those materials can be re-used between grants, such as descriptions of equipment and research facilities.

A stack of papers facedown on a table.
So. many. supporting documents.

The success rate for obtaining federal funding for your project varies by agency, year, and category of project/principal investigator, nicely tracked here (updated Dec 2019), and currently ranges from 8 – 30%. For example, “pilot” project (small projects to “seed” your long-term research), student-specific, or “new investigator” grants may have a higher rate of success because their applicant pool is restricted by eligibility. Competition is fierce, especially when federal agency budgets are cut or re appropriated.

If projects are not funded, they are returned with reviews from typically 2 – 4 experts in the field who provide comments and recommendations for strengthening the experimental design, or the presentation of the project itself. You might think that proposals are judged on the merit of the science alone, but the ability of the team to manage the project, and the research team, is also being evaluated. Principal investigators (researchers like me, leading the project) need to show that we have good ideas and the organizational skills to implement them, especially if the project spans multiple years or institutions.

Submitting a research proposal is worth celebrating – it represents weeks of effort – but especially during this time when we are all trying to keep our head above water, never mind accelerate or productivity. It’s important to take a few minutes to relax, work can wait, because ‘the grind’ will be there waiting for you when you get back.

Image of plastic wrapped over soil to inhibit weed growth.

NE IPM funded collaborative proposal!

I’m pleased to announce that a small grant proposal I am part of was just funded by the Northeastern Integrated Pest Management (IPM) Center! The proposal, “A Working Group on Tarping and Soil Solarization”, brings together researchers and food production professionals from across New England to identify the current use of tarping and soil solarization to prevent weed growth without the use of chemcials, as well as identify barriers to adoption of this practice, and develop research proposals to fill any knowledge gaps related to the use of these methods and their effect on crop production, weed suppression, soil microbiota, and the local ecosystem.

Led by Dr. Sonja Birthisel (UM), the working group team is comprised of Dr. Alicyn Smart (UM), myself, Master Nathalie Lounsbury (UNH), and Eva Kinnebrew (UVM). We will be joined by over a dozen other researchers across New England who perform agricultural research, along with dozens of ‘stakeholders’: producers and other food production professionals who have an interest in the group findings and would make use of any knowledge we generate.

Featured Image Credit: Soil Solarization, Wikimedia

Wild blueberries on a bush.

My first funded proposal at UMaine!

Now that I’m an assistant professor, a significant amount of my time is spent writing grant proposals to fund projects I’d like to do in the future.

Many large federal or foundational grants take up to a year from submission to funds distribution, and the success rate, especially for newly-established researches, can be quite low. It’s prudent to start writing well in advance of the due date, and to start small, with “pilot projects”.

To that end, I’m pleased to announce that Dr. Lily Calderwood and I just received word that the Wild Blueberry Commission of Maine is funding a pilot project of ours; “Exploration of Soil Microbiota in Wild Blueberry Soils“. We’ll be recruiting 1 – 2 UMaine students for summer/fall 2020 to participate in the research for their Capstone senior research projects.

Dr. Calderwood is an Extension Wild Blueberry Specialist, and Assistant Professor of Horticulture in the School of Food and Agriculture at UMaine. She and I developed this project when meeting for the first time, over coffee. We realized we’d both been at the University of Vermont doing our PhD’s concurrently, and in neighboring buildings! We got to chatting about my work in wheat soil microbial communities, and her work on blueberry production, and the untapped research potential between the two.

This pilot will generate some preliminary data to help us get a first look at the soil microbiota associated with blueberries, and in response to management practices and environmental conditions. From this seed funding, Lily and I hope to cultivate fruitful research projects for years to come!

Featured Image: Wild Maine Blueberries, Wikimedia

It takes a village to write a scientific paper

Every scientist I know (myself included) underestimates how long it will take to write, edit, and submit a paper.  Despite having 22 publications to date, I still set laughably-high expectations for my writing deadlines.  Even though scientists go into a project with a defined hypothesis, objectives, and workflow, by the end of data analysis we often find ourselves surprised.  Perhaps your assumptions were not supported by the actual observations, sometimes what you thought would be insignificant becomes a fascinating result.  Either way, by the time you have finished most of the data analysis and exploration, you face the difficult task of compiling the results into a meaningful paper.  You can’t simply report your data without giving them context and interpretation.  I’ve already discussed the portions of scientific manuscripts and how one is composed, and here I want to focus on the support network that goes into this process, which can help shape that context that you provide to your data.

One of the best ways in which we can promote rigorous, thoughtful science is through peer-review, which can take a number of forms.  It is worth noting, that peer-review also allows for professional bullying, and can be swayed by current theories and “common knowledge”.  It is the journal editor’s job to select and referee reviewers (usually 2 – 4), to compile their comments, and to make the final recommendation for the disposition of the manuscript (accept, modify, reject).  Reputation, and personal demographics such as gender, race, or institutional pedigree can also play a role in the quality and tone of the peer-review you receive. Nevertheless, getting an outside opinion of your work is critical, and a number of procedural changes to improve transparency and accountability have been proposed and implemented.  For example, many journals now publish reviews names online with the article after it has been accepted, such that the review does not stay blind forever.

Thorough reading and editing of a manuscript takes time.  Yet peer-reviewers for scientific journals almost unanimously do not receive compensation.  It is an expected service of academics, and theoretically if we are all acting as peer-reviewers for each other then there should be no shortage.  Unfortunately, due to the pressures of the publish-or-perish race to be awarded tenure, many non-tenured scientists (graduate students, post-docs, non-tenure track faculty, and pre-tenured tenure-track faculty) are reluctant to spend precious time on any activity which will not land them tenure, particularly reviewing.  Moreover, tenured faculty also tend to find themselves without enough time to review, particularly if they are serving on a large number of committees or in an administrative capacity.  On top of that, you are not allowed to accept a review if you have a conflict of interest, including current or recent collaboration with the authors, personal relationships with authors, a financial stake in the manuscript or results, etc.  The peer-review process commonly gets delayed when editors are unable to find enough reviewers able to accept a manuscript, or when reviewers cannot complete the review in a timely manner (typically 2 – 4 weeks).

I have recently tried to solicit peer-review from friends and colleagues who are not part of the project before I submit to a journal.  If you regularly follow my blog, you’ll probably guess that one of the reasons I do this is to catch spelling and grammatical mistakes, which I pick out of other works with hawk-like vision and miss in my own with mole-like vision.  More importantly, trying to communicate my work to someone who is not already involved in the project is a great way to improve my ability to effectively and specifically communicate my work.  Technical jargon, colloquial phrasing, sentence construction, and writing tone can all affect the information and data interpretation that a reader can glean from your work, and this will be modulated by the knowledge background of the reader.

I’ve learned that I write like an animal microbiologist, and when writing make assumptions about which information is common knowledge and doesn’t need a citation or to be included at all because it can be assumed.  However, anyone besides animal microbiologists who have been raised on different field-specific common knowledge may not be familiar with the abbreviations, techniques, or terms I use.  It may seem self-explanatory to me, but I would rather have to reword my manuscript that have readers confuse the message from my article.  Even better, internal review from colleagues who are not involved with the project or who are in a different field can provide valuable interdisciplinary perspective.  I have been able to apply my knowledge of animal science to my work in the built environment, and insights from my collaborators in plant ecology have helped me broaden my approach towards both animals and buildings.

No scientific article would be published without the help of the journal editorial team, either, who proof the final manuscript, verify certain information, curate figures and tables, and type-set the final version.  But working backwards from submission and journal staff, before peer-review and internal peer-review, there are a lot of people that contribute to a scientific article who aren’t necessarily considered when contemplating the amount of personnel needed to compose a scientific article.  In fact, that one article represents just the tip of the iceberg of people involved in that science in some way; there are database curators, people developing and maintaining open-source software or free analysis programs, laboratory technicians, or equipment and consumables suppliers.  Broadening our definition of science support network further includes human resources personnel, sponsored projects staff who manage grants, building operational personnel who maintain the building services for the laboratory, and administrative staff who handle many of the logistical details to running a lab.  It takes a village to run a research institution, to publish a scientific article, to provide jobs and educational opportunities, and to support the research and development which fuels economic growth.  When it comes time to set federal and state budgets, it bears remembering that that science village requires financial support.


Featured Image Credit: Kriegeskorte, 2012