A Highly Efficient Biocatalytic Conversion of Renewable Pectic Polysaccharide Biomass into Bioactive Oligogalacturonides

Abstract

The quest for an efficient biodegradation of pectic polysaccharides into sustainable oligogalacturonide (OG) products for a recent bioactivity study and application is currently underway. This study reported highly efficient degradation of pectin into OGs (DP2–DP10) by a polygalacturonase (i.e., AnPG28A from Aspergillus niger). The activity of AnPG28A toward low-methoxyl pectin reached 42897 units/mL, and the protein concentration was 7.7 g/L after 96 h, the highest of the reported values. For further processing of commercial pectins to produce OGs, the physicochemical properties of different kinds of commercial pectins on the market were characterized. The preparation of high-purity OG standards (DP2–DP7) was achieved with polygalacturonic acid as a substrate by high-performance liquid chromatography, which helps the preparation of OG, its usage, and the study of its functional characteristics. Moreover, further OG production pilot experiments were performed on the basis of a response surface methodology. The OG yield was approximately 65% on the pilot scale. AnPG28A has many advantages, such as easy, inexpensive preparation, greenness, and excellent catalytic activity. The high yield and quality of OGs and the sustainability and eco-friendly process support the forthcoming commercialization of the biocatalytic transformation of pectin into high-value-added OGs.

Characterization of Two Novel Rumen-Derived Exo-Polygalacturonases: Catalysis and Molecular Simulations

“…Loop 1 in endo-polygalacturonases is involved in forming one “wall” of the “substrate path”, contributing to a tunnel-like active site, rather than orientating to the active center [ 4 , 5 , 10 , 11 , 40 ]. The substrate tends to lay along the tunnel-like active site in endo-polygalacturonase, which randomly cleaves α-1,4 glycosidic bonds via a single-attack manner, generating pectic oligogalacturonides and monomers [ 4 , 9 , 41 , 42 ]. In contrast, loop 1 in exo- polygalacturonase [ 19 , 30 ] and exo-poly-α-digalacturonosidase [ 5 ] formed the “back wall” of the substrate-binding cavity, forming to a pocket-like active site ( Figure 5 and Figure S2 ).…”

Fungus Polygalacturonase-Generated Oligogalacturonide Restrains Fruit Softening in Ripening Tomato

“…Short OGs have advantageous activities, such as the induction of fruit defense responses, in delaying fruit softening. 32 Here, short OGs generated by fungal PG were effective elicitors that could be perceived by fruit hosts and then controlled the self-softening process. In the OG mixture, the lower-molecular-weight fraction in fractions B-4 and B-5 has a greater advantage than B-1 and B-2.…”

Effect of Oligogalacturonides on Seed Germination and Disease Resistance of Sugar Beet Seedling and Root

“…The preparation of oligogalacturonides (OGs) was achieved through endo-polygalacturonase ( An PG28A) [ 29 ] degradation of sunflower plate pectin whose molecular weight, degree of esterification, and uronic acid content are about 280 kD, 24%, and 90%, respectively. An PG28A acts on the alpha-1,4-linked galacturonic acid backbone in pectin through endo-mode.…”