Xavier University of Louisiana (XULA) is a small, minority serving undergraduate institution based in New Orleans, Louisiana (US). With a total undergraduate population of about 2,700, the Biology department is the largest, with over 800 majors, the majority of whom are interested in biomedical careers after graduation. XULA was formed a hundred years ago to offer quality education to students from underserved and minority populations, specifically African Americans and American Indians, for whom, few if any, opportunities to further themselves existed at that time. True to the University Mission, even today the Biology department is home to both high achievers as well as students from disadvantaged backgrounds who are underprepared for college education but have exhibited a strong will to work hard and succeed. With the support of its administration XULA faculty have a history of "doing what it takes" to overcome even the most extreme disasters like the devastation caused by Hurricane Katrina (2005) and the more recent COVID pandemic. Through all these times the one issue that has continued to be a challenge is that of student retention and persistence in STEM. This paper will outline the gains made in this area through curricular revisions particularly in the very important freshman year (which students find difficult to pass/clear) as well as describe a newly developed project with excellent applications in didactic and experiential learning for undergraduate students.

Briefly, this project involves chemical and microbiological analysis of soil samples from environmentally distinct areas of "Bonnet Carre Spillway" (B.C. Spillway), a unique ecological region (12 miles from New Orleans) which endures periodic flooding of the Mississippi (MS) river water carrying both contaminants and nutrients from over 10 states for downstream levee failure prevention (the levee being built to protect the city of New Orleans). The B.C Spillway region is exciting because certain 'pockets' receive year-round seepage of the MS river water, while other areas get an influx of the river water ONLY when the levee gates are opened. So, soil samples from this region with such natural 'built-in' controls serve as excellent model systems for isolating and studying organisms (bacteria and fungi) that have adapted to these characteristic environments. To the best of our knowledge, such systematic microbial analyses in the B.C. Spillway have not been conducted. Preliminary results of four samples including a control identified through their GPS coordinates show distinct chemical properties (pH, presence of heavy metals or not, etc.) as well as differing amounts and type of growth on selective media (for example, Rose Bengal agar for fungi) using serial dilution techniques. Further subculturing is currently ongoing to obtain pure cultures for phenotypic analysis using microscopy. Students involved in developing this project are finding it engaging and "fun". For pure culture analysis, initial Gram staining and biochemical tests will be conducted in the department while more advanced identification of the organisms at species and strain level will be achieved collaboratively with larger institutions. In closing, this project is cost effective, highly conducive for developing engaging teaching and research modules for all undergraduate levels and shows potential for discovering new organisms (for example, with bioremediation capabilities).

Keywords: Student engagement, Research-based education, Improving STEM retention.