2011 Annual Report
1a.Objectives (from AD-416)
The overall goal is to support the rural U.S. agricultural economy and provide health-related benefits to the American consumer by developing bioactive food ingredients and biobased products from fruit and vegetable processing residues such as sugar beet pulp, citrus peel and cranberry pulp.
1b.Approach (from AD-416)
A multidisciplinary biorefinery approach will be used to develop health-related and biobased co-products from plant cell wall polysaccharides in fruit and vegetable processing residues. Plant cell wall polysaccharides will be converted into biomedical materials for human tissue regeneration, cosmetic personal care products, carriers of bioactive substances for colon-specific delivery and to produce synbiotics, in which probiotic bacteria are encapsulated in a prebiotic. Plant cell wall oligosaccharide-based prebiotics will be isolated from agricultural processing residues rich in pectins and hemicelluloses. The hypothesis that prebiotics can selectively promote the growth of gut bacteria associated with lean tissue growth to potentially control obesity will be tested. Plant cell wall oligosaccharides will also be screened for biological activity such as preventing the adhesion of pathogenic bacteria to intestinal epithelial cells, immunomodulation, and induction of cancer cell apoptosis. Bioplastic composites will be designed with bacteriocins for control of food-borne pathogens with active packaging. Weight-bearing, light weight bioplastic composites will also be produced with construction and consumer product applications in mind.
The collaborative research brings 6-8 graduate school students to work with ERRC scientists on the development of active packaging materials, synbiotics and antiadhesive oligosaccharides. A preliminary study on how the crystallinity of poly(lactic acid) influences the release of pre-incorporated bioactives was conducted and a manuscript is in preparation. The research showed that there is a proportional relationship between the release rate of pre-incorporated bioactives and the crystallinity of the polymers. By altering the ratio of L- and D- isomers, the resultant polymeric materials vary with crystallinity. The bioactives pre-incorporated in the amorphous zone of poly(lactic acid) release at a higher rate compared to the crystalline regions. This finding is of significance for designing packaging materials. Pectic oligosaccharide prebiotics were used with alginate to encapsulate probiotic bacteria. Pectic oligosaccharides scored as well as fructo-oligosaccharides and inulin for the growth of probiotic bacteria in synbiotics. The prebiotics protected the viability of these bacteria in the synbiotic during four months of refrigerated aerobic storage. The structure of pectic oligosaccharides that provide optimal activity to prevent adhesion of E. coli O157:H7 to HT29 cells is under investigation.
Research progress was monitored by site meetings, telephone calls and e-mail.