Combinatorial enzyme technology: Conversion of pectin to oligo species and its effect on microbial growth

Authors: Wong, Dominic; Feng, Doris; Batt-Throne, Sarah; Orts, William

Submitted to: American Chemical Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 12/27/2016
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Plant cell wall polysaccharides, which consist of polymeric backbones with various types of substitution, were studied using the concept of combinatorial enzyme technology for conversion of agricultural fibers to functional products. Using citrus pectin as the starting substrate, an active oligo species has been isolated that suppressed the growth of a test microorganism Escherichia coli ATCC 8739. It was found that the inhibitory effect increased with the concentration, with a MIC of 0.4%. The antimicrobial effect was sustained for three days and possibly longer. The species had high intensity at A235 indicating a double bond character, and was highly sensitive to permanganate oxidation. It showed positive on total carbohydrate based on the phenol-sulfuric acid assay, but negative on reducing sugar based on the DNSA assay. From this and also the study on arabinoxylan, the presence of reactive double bonds and the size of the oligo species may be the contributing factors to the inhibitory effect. Oligosaccharides have gained popularity as functional food ingredients, and in more recent years as alternatives for antimicrobial growth performance promoters in animal production. In both regards, they are used in sub-minimum inhibitor concentrations acting to modulate the microbiota composition.