Quantification of total and Pro-vitamin A Carotenoids from Solid Samples of Corn and Cassava Using a flatbed scanner or JPEG Images and ImageJ Software
Authors:Albert Chen, Caroline Chou, Bryce Jensen, Josef Lerer, Samuel Pan, Jessica Williams
Mentor:Roman Ferede, Physical Science Department, Santa Monica College
Carotenoids are yellow to orange pigments that are found in many plants. Few of these carotenoids, such as beta carotene, are precursors to vitamin A. The goal of this study is to find a rapid, inexpensive screening method for quantification of carotenoids in plants, such as corn and cassava. This information can be used to screen hundreds of samples before subjecting them to a more expensive and time-consuming HPLC method and aid breeders in breeding crops that have high content of pro-vitamin A carotenoids.
In previous research in this laboratory, carotenoids were extracted from corn, separated by thin layer chromatography and quantified using a flatbed scanner and ImageJ software. The aim of this research is to bypass the extraction process and perform the analysis on solid samples to quantify carotenoids in corn and pro-vitamin A carotenoids in cassava. This process is much less time consuming and also avoids the use of expensive organic solvents and generating organic waste and thus minimizing the negative impact to the environment.
Different inbred lines of corn and cassava were ground into fine powder or paste and then placed in clear plastic sample discs. The discs were either scanned by Epson 300V scanner, or captured by a high resolution camera, and the images were quantified using Image J’s Gel analysis tool, transforming the scanned images into plotted intensity profiles. The intensities were compared to the intensity of a standard sample, providing the relative densities of pigments in each sample. The densities were found to be close to the expected relative carotenoid concentration of the samples.
This study shows that it is possible to use the images of solid samples and quantify the densities of pigments, thus determining which samples will be further analyzed using a more expensive analysis method such as high performance liquid chromatography.