2008 Annual Report 1a.Objectives (from AD-416) 1. Functional modification, leather and leather byproducts: Develop a foundation for the use of new chemical and biochemical technologies (a) in the production of high quality chrome-free leathers, (b) in expanding the range of high value biomaterial applications for solubilized proteins from leather byproducts. 2. Functional modification, wool: Modify wool to impart functionality for improved performance and expanded uses of domestic wool. 1b.Approach (from AD-416) 1. Collagen modification is central to both tanning and byproduct utilization. (a) To develop a basis for designing or selecting effective sustainable tanning agents, the results of theoretical and experimental model studies will be integrated to give the best overall evaluation. Targets for chrome-free tanning agents will include natural products (tannins, genipin), enzymes for protein modification (transglutaminase, oxidases), and organic chemicals (aldehydes, acrylates). (b) Gelatin byproducts from leather processing will be evaluated alone and in combination with other proteins from renewable agricultural resources as potential coatings and fillers for use in leather or wool processing. Partially hydrolyzed collagen recovered from leather waste will also be combined with fibrous protein waste products for the preparation of novel composite materials with useful properties, such as high strength and thermal stability, for use in a variety of industrial applications, such as "bonded" leather and shoe inner soles. 2. The ERRC process (patent pending) of treating wool fabric for shrinkage control will be evaluated on wool blended with other natural and synthetic fibers, and yarn-dyed fabrics. Chemical and biochemical modifications of intact wool to add functionality will be evaluated for improved properties, such as softness, comfort, resistance to shrinkage, improved flame retardancy, and resistance to photodegradation. Collagen hydrolysates, or other proteinaceous carriers, will be applied to wool fabric as a vehicle for introducing agents that impart such properties as improved whiteness, resistance to ignition, and photoprotection. 3.Progress Report Computational methods were developed to simulate noncovalent interactions of tannins with collagen. Both H-bonding and hydrophobic sites for the interaction of catechin, a model tannin, with collagen were identified. (NP 306, Quality and Utilization of Agricultural Products; Component1. Quality Characterization, Preservation, and Enhancement; Problem Area 1a. Definition and Basis for Quality) Chemically and enzymatically-modified biopolymers were prepared, characterized, and applied, in small pilot experiments, to unfinished leather; treated samples were then finished and evaluated. The modified biopolymers appear, in micrographs, to coat the fibers. Subjective properties of the treated leather were improved over controls while mechanical properties were not affected. Experiments were designed for scaling this work up to full pilot scale. Keratin, wool protein, was found to have permanent affinity for wool fibers or textiles and to control dimensional stability without strength loss. Nanoparticle silver, formed under various light conditions to give a variety of sizes and shapes, was applied to wool via keratin hydrolysates to confer antimicrobial properties to wool. 4.Accomplishments 1. Leather improved by application of agricultural by-products. Leather produced from hides collected in springtime often has loose grain, excessive wrinkles and feels flat. A filler treatment based on byproduct proteins from dairy and meat processing was developed and applied to leather prior to finishing. When the treated leather was finished, its mechanical and subjective properties were significantly improved over controls, presenting more cutting area and thus a better economic return for the processor. (NP 306, Quality and Utilization of Agricultural Products; Component 2. New Processes, New Uses, and Value-Added Foods and Biobased Products; Problem Area 2b. New uses for agricultural by-products) 5.Significant Activities that Support Special Target Populations None. 6.Technology Transfer Number of New Commercial Licenses Executed 8 Number of Web Sites Managed 1 Review Publications Cardamone, J.M. 2007. Enzyme-mediated crosslinking of wool part I: transglutaminase. Textile Research Journal. 77(4):214-221. Cardamone, J.M., Phillips, J.G. 2007. Enzyme-mediated Crosslinking of Wool Part II: Keratin and Transglutaminase. Textile Research Journal. 77(5):277-283. Cardamone, J.M. Keratin Transamidation. 2008. International Journal of Biological Macromolecules. 42(5):413-419. Taylor, M.M., Marmer, W.N., Brown, E.M. 2008. Effect of Fillers Prepared from Enzymatically Modified Proteins on Mechanical Properties of Leather. Journal of American Leather Chemists Association. 103(4):128-137.