Exploring the Binding Properties of Phytoglycogen in its Native and Acid-Hydrolyzed States

Abstract

Phytoglycogen (PG) is a polysaccharide made up of anhydroglucose units that occurs in nature as compact, highly branched nanoparticles. In this thesis, I investigate interactions of native and acid-hydrolyzed PG with bioactive compounds using different experimental techniques. To study the interaction between acid-hydrolyzed PG and ConA, SPR sensors were functionalized with acid-hydrolyzed PG using an intermediate monolayer of 4-mercaptophenylboronic acid. ConA was found to bind to acid-hydrolyzed PG with an equilibrium association constant 𝐾 = 2.31 ± 1.38 × 105 M-1. I also investigated the effect of PG to enhance the solubility of the water-insoluble carotenoid ASX in water. To explore this, I evaluated three different protocols: evaluating them through UV-vis spectroscopy and taking the most effective technique to characterize the binding affinity through SPRi. We obtained evidence for binding of ASX-PG complexes to the PG functionalized sensor surface due to the presence of the ASX in the ASX-PG complexes.