Meet our People

 Lindsay Leonard, Graduate Student

LeonardLindsay Leonard is a current graduate student in Dr. Tzu-Wen Cross’s lab working towards an M.S. degree in Nutrition Science. Lindsay is from Greendale, Wisconsin, and received her B.S. in Microbiology from the College of Biological Sciences at the University of Minnesota Twin Cities in 2019. She worked as a Research Intern at Arm & Hammer Animal Nutrition from 2017-2019 studying the impact of probiotics on livestock and poultry. She then worked as a full-time Poultry Research Scientist and Food Safety Research Scientist at Arm and Hammer for a year before attending Purdue.Lindsay uses an anaerobic chamber to culture many of her oxygen-sensitive strains of bacteria.

Her current project is focused on studying equol, a microbial metabolite of soy isoflavone daidzein. Soy isoflavones are plant-derived phytoestrogens that are structurally similar to mammalian estrogens. Equol is known to have the highest binding affinity to estrogen receptors among all soy isoflavones and mimics the effects of estrogen in the human body. Humans lack the enzymes needed to convert daidzein into equol and depend on the bacterial enzymes in our gut microbiome for this conversion to produce equol. However, less than half of the Western population has these gut bacteria to be classified as an “equol producer”. Through associations, research has shown that those who are equol producers benefit greater from soy intake in areas such as osteoporosis and cardiometabolic diseases, particularly in post-menopausal women. As conventional rodents are highly efficient equol producers due to the natural microbiome harbored, the benefits of being an equol producer are difficult to discern. Lindsay aims to develop a model system that can be used to compare equol producers to non-equol producers by colonizing germ-free
Lindsay’s two cats Gloria (grey) and Layton (black and white).mice with synthetic microbiomes of defined microbial communities. Once established, this model system can then be used in future studies to determine if a cause-and-effect relationship with the benefits observed from being an equol producer exists.

During her time living in Indiana, Lindsay has also expanded her family, adopting two loving cats. She adopted her older cat, Gloria, in August of 2020 and recently adopted her younger cat, Layton, in May of 2021.


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Marie Allsopp, DrPH, RD, LD, CHES

Dr. Marie AllsoppDr. Marie Allsopp has been a Clinical Assistant Professor in the Department of Nutrition Science at Purdue University since January 2019. Dr. Allsopp earned a BS degree in Dietetics & Nutrition from Florida International University in Miami. She later earned MS and MPH degrees from The University of Tennessee, Knoxville, with concentrations in Public Health Nutrition and Community Health Education, respectively. Prior to joining the academy, Marie Allsopp accrued over a decade of professional experience as a registered dietitian nutritionist (RDN) in clinical, community, and customer service settings in North Georgia and South Florida. Marie Allsopp also holds a doctor of public health (DrPH) degree from the University at Albany, State University of New York, with a concentration in Social Behavior and Community Health. Before becoming a member of faculty at Purdue, Dr. Allsopp held full-time posts at Miami University (OH) and Mississippi State University.

Dr. Allsopp is passionate about pursuing pedagogical practices to increase undergraduate student engagement and promote diversity and inclusion. Her line of scholarship of teaching and learning includes using multi-media to engage students, collaborative learning, service-learning, flipped classrooms, and team-based learning. In the fall of 2019 Marie Allsopp was a fellow of Instruction Matters: Purdue Academic Course Transformation (IMPACT). She has received recognition professionally as a practitioner, program director, and assistant professor for her dedication and service. In the spring of 2021 Marie Allsopp was awarded the inaugural “Prioritizing Diversity and Inclusion in Nutrition and Dietetics: Overcoming Obstacles to RDN Recruitment, Education and Advancement Fellowship” from the Academy of Nutrition and Dietetics Foundation. 
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Tzu-Wen Cross, PhD

Dr. Tzu-Wen CrossDr. Tzu-Wen Cross is an Assistant Professor in the Department of Nutrition Science at Purdue University. She earned her B.S. in Human Nutrition and Dietetics from Taipei Medical University in Taiwan, M.S. in Nutrition Sciences from the University of Missouri-Columbia, and Ph.D. in Nutrition Sciences from the University of Illinois at Urbana-Champaign. Dr. Cross was an NIH T32 Postdoctoral Fellow in the Translational Cardiovascular Science Training Program at the University of Wisconsin-Madison before joining Purdue. Prior to starting her graduate career, Dr. Cross worked as a licensed and registered dietitian in Taiwan helping patients undergoing bariatric surgeries with their dietary needs.
Dr. Cross’ research largely focuses on understanding how our gut microbiome impacts health and disease, intending to identify dietary strategies to modify disease susceptibilities and reduce the risk of disease. Diseases with sexual dimorphism (e.g., obesity, inflammatory bowel disease, certain forms of cancer, and Parkinson’s disease) are of particular interest, as the microbes harbored in our gut can modulate sex hormones and affect binding affinity and hormonal homeostasis. Due to the complex nature of microbial communities residing in our gastrointestinal tract, Dr. Cross’ research team mainly utilizes rodent models to explore host-microbial interactions to infer human health. Specifically, a mouse model free of any types of microorganisms (i.e., germ-free) is utilized, so that they can be colonized with specific microbial communities of interest, such as those coming from the human gut. Because diet is among the most significant and modifiable determinants of the gut microbiome, we aim to develop therapeutically useful gut microbiome modulators to improve human health.


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