Project Number: 6618-41000-015-00
Project Type: Appropriated

Start Date: Jul 28, 2010
End Date: Jul 27, 2015

Objective:
1. Identify and characterize biologically active compounds in citrus peel and associated processing byproducts for potential as value-added products to promote human health. a) Advance the discovery, isolation, and structural characterization of compounds from peel, molasses, and ethanol conversion residues and from lipid-soluble constituents of peel oil residues for biotesting purposes. b) Discover new beneficial pharmacological actions of citrus byproduct compounds, validate these biological actions in animals, and characterize the associated modes of action, pharmacokinetics and bioavailability. 2. Identify citrus processing waste compounds that can be used as value-added products to control major citrus and other plant diseases. a) Discover anti-microbial compounds from citrus processing waste. b) Characterize the influences of citrus byproduct compounds on pathogen virulence and microbial ecology. 3. Develop economical recovery methods for biologically active classes of compounds in citrus processing waste. 4. Develop value-added food materials from polysaccharide constituents of citrus byproduct waste streams.

Approach:
Develop new value-added uses of citrus processing byproducts by exploiting the bioactive constituents (secondary metabolites) and specialty food fibers of these citrus processing materials. Fractions enriched in specific phenolic compounds will be isolated and evaluated as potential value-add materials for food and health applications. New, untested compounds, novel compositions with other citrus compounds, and new biological applications will be pursued. To achieve this, research will be directed towards 1) discovering new beneficial biological actions of citrus byproduct compounds, 2) validating these biological actions in vivo, 3) characterizing modes of action, pharmacokinetics, and bioavailability of bioactive citrus byproduct derived materials, and 4) producing specialty fibers to fill a wide range of high value food applications. Approaches to discover new biological actions will extend to studies of the influences of citrus processing waste compounds on microbial pathogen virulence and ecology, with an aim towards controlling microbial pathogens in citrus production. Broad profiles of compounds will be tested against plant pathogens, with an emphasis on important citrus microbial pests. Another direction to this work is the development of new syntheses and analytical methods for the successful production of pectin materials possessing wide ranges in functionalities to fill high-value food and pharmaceutical applications. Emphasis will be placed on the production of these specialty fibers through selected actions of known hydrolytic enzymes and through site specific chemical modifications. Critical to any future commercialization of value-added citrus byproduct materials is the development of economical recoveries of the modified polysaccharide fibers and secondary metabolites. Effective fractionations of byproduct streams into specific classes of secondary metabolite compounds and structural polysaccharides will be developed.