Modeling protein structures in feed and seed tissues using novel synchrotron-based analytical technique

Traditional “wet” chemical analyses usually looks for a specific known component (such as protein) through homogenization and separation of the components of interest from the complex tissue matrix. Traditional “wet” chemical analyses rely heavily on the use of harsh chemicals and derivatization, therefore altering the native feed protein structures and possibly generating artifacts. The objective of this study was to introduce a novel and non-destructive method to estimate protein structures in feed and seeds within intact tissues using advanced synchrotron-based infrared microspectroscopy (SFTIRM). The experiments were performed at the National Synchrotron Light Source in Brookhaven National Laboratory (US Dept. of Energy, NY). The results show that with synchrotron-based SFTIRM, we are able to localize relatively “pure” protein without destructions of the feed and seed tissues and qualify protein internal structures in terms of the proportions and ratios of α-helix, β-sheet, random coil and β-turns on a relative basis using multi-peak modeling procedures. These protein structure profile (α-helix, β-sheet, etc.) may influence protein quality and availability in animals. Several examples of feed and seeds were provided. The implications of this study are that we can use this new method to compare internal protein structures between feeds and between seed verities. We can also use this method to detect heat-induced the structural changes of protein in feeds.