Title: EFFECT OF PLANT-TYPE (PURPLE VS. TAN) AND MOLD INVASION ON CONCENTRATIONS OF 3-DEOXYANTHOCYANIDINS IN SORGHUM GRAIN Author
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: January 27, 2005
Publication Date: February 19, 2005
Citation: Seitz, L.M. 2005. Effect of plant-type (purple vs. tan) and mold invasion on concentrations of 3-deoxyanthocyanidins in sorghum grain. Proceedings of the 24th Biennial Grain Sorghum Research & Utilization Conference. Meeting Abstract. p. 29. Technical Abstract: Weathering and mold invasion degrades the quality of sorghum grain, including discoloration which could be undesirable in utilization of sorghum in foods and other applications. This research was conducted to identify compounds causing discoloration and to determine how their concentrations were affected by pre-harvest mold invasion. Colored 3-deoxyanthocyanidin compounds, apigeninidin (AP) and luteolinidin (LU), were identified in samples of grain from purple and tan plant-type hybrids with varying degrees of moldiness grown on experimental plots in Kansas and Nebraska. An ergosterol assay was used to measure degree of mold invasion. The 3-deoxyanthocyanidins were identified by using HPLC coupled with UV-Vis and mass spectroscopy to compare observed compounds with authentic standards. Concentrations of AP and LU were similar and ranged from <0.1 to 0.8 and 0.1 to 33 ug/g in grain with tan and purple plant-types, respectively. In grain with purple plant-type, concentrations of AP and LU were high in samples with high ergosterol content, indicating that mold invasion greatly enhanced production of the colored compounds. AP, LU, and ergosterol were also found in glumes. These findings will aid plant breeders in evaluating genotypes for susceptibility to mold invasion and production of colored compounds, and will help users determine quality of grain for various food and industrial applications.