Differentiation of Capsicum Species via Protein Extraction and SDS-PAGE Analysis: A Two-Day Experiment for Undergraduate Biochemistry Laboratories

Trey Polvadore, Brittney P. Cooper, Michele R. Harris

Research output: Other contribution


The Capsicum genus is comprised of more than 200 varieties of pepper plant that collectively represent only five cultivated spices. As a result of extensive cross-breeding, an 88% similarity in protein coding DNA has developed. While this has made species determination based solely on physical appearance all but impossible, the 12% difference in protein coding DNA has led to subtle differences in translated protein. SDS-PAGE analysis facilitates the generation of protein banding patterns that, after careful analysis, was used to differentiate one variety of pepper from another. This project was used to distinguish between pepper plant species and was carried out as a senior mini-research project in which students had four weeks to develop the project. THe students independently modified an existing protocol to employ safer chemicals and more easily obtainable materials needed in the experiment. After the students developed the protocols, they were then required to lead other students in the laboratory procedures. The educational aspect of this project was successfully completed in two laboratory periods which allowed the students to use a variety of biochemical techniques (such as centrifugation, vacuum filtration, and SDS-PAGE) as well as more specialized procedures including natural product extraction, tissue preparation, and the handling of liquid nitrogen.

Original languageUndefined/Unknown
StatePublished - Apr 10 2012

Publication series

NameUndergraduate Research Conference

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