Search for: All records

Water quality analysis of Philadelphia County surface waters have indicated that storm events alter the concentrations of pollutants such as polycyclic aromatic hydrocarbons (PAHs), antibiotics, heavy metals, and other pollutants, which could impact aquatic organisms' diversity as well as human health. However, there is limited knowledge regarding the microbial communities in these environments and their responses to these pollutants. To address this knowledge gap, culturing and analysis of genomes isolated from surface water samples was carried out at two different time points: one under average conditions (SW1) and another three days after a storm event (SW2). Colorimetric water quality assays were also employed to assess the levels of common pollutants in waterways and observe alterations in the relative concentrations of various chemicals in the Schuylkill River after storm events. Gram staining, and culture analysis of isolated colonies from surface waters in Philadelphia County waterways was performed to understand microbial diversity and the principles of bacterial identification. Genomic DNA was extracted from bacteria concentrated via filtration. PCR amplification of the 16s rRNA gene was performed in preparation for genomic sequencing. Genomic sequencing of samples from various waterways was performed and analyzed using bioinformatics software to identify microorganisms and classify taxa. The results demonstrate that storm events influence the diversity of microorganisms in the Delaware River Watershed. Further analysis of pollutant levels and the metagenomic data will be needed to further elucidate the correlation between specific pollutants and potential pathogens as well as the influence of said pollutants on microbial diversity. 

Seafood mislabeling occurs when a market label is inaccurate, primarily in terms of species identity, but also regarding weight, geographic origin, or other characteristics. This widespread problem allows cheaper or illegally-caught species to be marketed as species desirable to consumers. Previous studies have identified red snapper (Lutjanus campechanus) as one of the most frequently mislabeled seafood species in the United States. To quantify how common mislabeling of red snapper is across North Carolina, the Seafood Forensics class at the University of North Carolina at Chapel Hill used DNA barcoding to analyze samples sold as “red snapper” from restaurants, seafood markets, and grocery stores purchased in ten counties. Of 43 samples successfully sequenced and identified, 90.7% were mislabeled. Only one grocery store chain (of four chains tested) accurately labeled red snapper. The mislabeling rate for restaurants and seafood markets was 100%. Vermilion snapper (Rhomboplites aurorubens) and tilapia (Oreochromis aureusandO. niloticus) were the species most frequently substituted for red snapper (13 of 39 mislabeled samples for both taxa, or 26 of 39 mislabeled total). This study builds on previous mislabeling research by collecting samples of a specific species in a confined geographic region, allowing local vendors and policy makers to better understand the scope of red snapper mislabeling in North Carolina. This methodology is also a model for other academic institutions to engage undergraduate researchers in mislabeling data collection, sample processing, and analysis.