Stability of dhurrin and HCN release in dried sorghum samples

<p>Sorghum contains the cyanogenic glucoside dhurrin. The hydrolysis of dhurrin leads to the release of HCN, which can be toxic to livestock feeding on sorghum. Management strategies include the utilization of sorghum as hay. The hay making process has been reported to reduce dhurrin content; however, the dynamics of this process are not well understood. In this study, quantitative analyses were conducted to measure changes in dhurrin content of diverse sorghum genotypes over time and the release of HCN in dried samples under varying rehydration methods.</p>

<p>Contrary to expectations, dhurrin content was shown to be stable during the drying process and for up to two months in dry tissue samples. HCN release from dried samples decreased over time when tissue samples were rehydrated with water. Subsequent studies demonstrated that dhurrinase2 became inactive in tissue samples rehydrated with water; thereby, slowing slowing the conversion of dhurrin to HCN. Rehydration studies using a modified <em>In vitro</em> Dry Matter Digestibility Assay demonstrated that rumen fluid expedited the quick release of HCN.</p>