Undergraduate Research Programs in Chemistry

“Examining binding affinity of RecA to mutation sites known to cause drug resistance in Mycobacterium tuberculosis with a homemade DSLR documentation system”. Kenneson, J. School of Mathematics and Sciences, Wayland Baptist University, Plainview, TX, USA.

A high-end DSLR camera was employed for analysis of protein-DNA interaction using chemiluminescent electrophoretic mobility shift assays (EMSAs) in order to study binding affinity of DNA repair protein, RecA, and selected Mycobacterium tuberculosis oligomers. Mini-format chemiluminescent, fluorescent, and large-format chemiluminescent EMSAs were used to determine percent RecA binding. Decrease in free DNA signal indicates RecA did bind to DNA, though a bound DNA band was not resolved in any of the three types of EMSAs. Future research will involve further examination of this protein-DNA interaction in order to determine why the complex is not migrating into the EMSAs. The culmination of the last three years of research has shown that the DSLR documentation system has a multitude of applications not know that could prove to be beneficial to many people.

“Soxhlet extraction of capsaicinoids from habanero, piquin, and serrano peppers”. Duffield, K.; Rivera, A.; Sandoval, E. School of Mathematics and Sciences, Wayland Baptist University, Plainview, TX, USA.

The Scoville Scale is a subjective scale obtained through individual taste tests that ranks peppers based on the amount of sugar water it takes to take the heat out of capsaicin extracted from a pepper. This test is performed on individuals, and is subject to variances in sensitivity and amount of heat receptors from person to person, causing it to lose representative aspects. Capsaicin is an alkaloid chemical that is the principal pungent constituent of hot peppers that are widely used as food additives. But how much capsaicin is contained in your average pepper, and is that relatable to the number of Scoville units assigned to each pepper? Capsaicin was extracted from serrano, habanero, and piquin peppers using a Soxhlet extraction. Each pepper extraction along with a capsaicin standard were dissolved in methanol and further characterized via HPLC (C18-0-75% methanol gradient over 45 min). The capsaicinoid masses were then compared and ranked based on percent of capsaicin by weight. It was predicted that, based on Scoville units, the Habanero pepper would have the most capsaicin content followed by the Piquín and Serrano peppers. Results showed that predictions were correct based on the Scoville scale. Using soxhlet extraction combined with HPLC methods demonstrates a more chemically analytical approach to determine how spicy peppers truly are.