ARS | Publication request: High-throughput micro plate assays for screening flavonoid content and DPPH-scavenging activity in sorghum bran and flour

Submitted to: Journal of the Science of Food and Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 26, 2012
Publication Date: March 14, 2012
Citation: Herald, T.J., Gadgil, P. and Tilley, M. 2012. High-throughput micro plate assays for screening flavonoid content and DPPH-scavenging activity in sorghum bran and flour. Journal of the Science of Food and Agriculture. 92:2326-2331.

Interpretive Summary: A method was developed to determine the amount of health promoting compounds in sorghum. The new method proved to be almost three times faster and more cost effective than conventional methods. This method will be ideal for breeders that need to screen large quantities of experimental sorghum lines for health promoting benefits.

Technical Abstract: Rapid, 96-well microtiter assays were compared to conventional assays for quantifying total phenolic content, flavonoid content, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) in sorghum grain. The 96-well assays exhibited a correlation of >0.9 to the conventional assays. The 96-well assays allowed for up to 64 samples to be run per day compared to 20–24 samples (depending on the test) for the conventional methods. The 96-well assays had excellent accuracy (97.65–106.16% recovery), precision (1.06–8.28 CV%), and reproducibility (1.32–2.13% interday and 1.36–2.09% intraday CV%). These assays proved to be rapid, accurate, and highly reproducible, and yet required less solvent and consumables. These assays provide an efficient means for high-throughput testing of a large number of samples.