Utilization of Corn Silk for GMO Detection Through Real-Time PCR

Purpose Corn silk is a fiber-rich byproduct obtained during corn processing. The present investigation deals with the purpose of GMO detection and quantification and comparison of DNA extraction in corn silk which is considered generally a waste product. Method A comprehensive analysis of extracted DNA quality, extraction cost, time, and PCR amplification was performed. Samples were homogenized using three different methods i.e. tissue lyser (CSK-TL) liquid nitrogen (CSK-LN), and grinder (CSK-RG). The homogenized samples from different methods were subjected to scanning electron microscopy (SEM) to access the effectiveness of homogenization methods. Afterward, DNA extraction was carried out using three different Kits QIAGEN DNeasyMericon Food Kit, eurofins|GeneScan GENESpin DNA isolation Kit, and PENICON EZ-10 Spin Column Genomic DNA Miniprep Kit. Furthermore, the fluorometric assay was done using Qubit fluorometer 3.0 for quantification of the extracted DNA. The quality of the DNA was accessed on 1.5% agarose gel. Results The scanning electron microscopy (SEM) technique displays observable differences among the three homogenization methods. As compared to the other two methods tissue lyzer (CSK-TL) shows the finest particle image. Whereas, the images of liquid nitrogen (CSK-LN), as well as a grinder (CSK-RG) treated sample, show granulated particles. DNA extraction of homogenized samples was carried out using three different kits named QIAGEN DNeasyMericon Food Kit (Kit 1), eurofins|GeneScan GENESpin DNA isolation Kit (Kit 2), and PENICON EZ-10 Spin Column Genomic DNA Miniprep Kit (Kit 3). Kit 1 showed a yield of 122.4 ng/µl, whereas Kit 2 and Kit 3 gave 99.6 and 40.1 ng/µl respectively. By using gel electrophoresis technique the band size of corn silk genomic DNA was above 1000 bp. Conclusion DNA extracted using waste material (corn silk) can be used for GMO analysis through the Real-Time PCR technique. Among different grinding techniques compared, the Tissue lyzed sample (CSK-TL) displayed the best homogenization and the highest quantity of DNA using the QIAGEN DNeasyMericon Food Kit. This method demonstrates the utility of the waste products for tracing the GMO status.