Structure and Characterizations of Different Hydrophobically Modified Phytoglycogen Nanoparticles

This study aimed to chemically modify natural phytoglycogen (PG) nanoparticles with three different alkenyl succinic anhydrides to characterize their physicochemical properties and assess the feasibility of using the modified PG nanoparticles (octenylsuccinic anhydride, (OSA)-PG; dodecenylsuccinic anhydride, (DDSA)-PG; and octadecenylsuccinic anhydride, (ODSA)-PG) as carriers for hydrophobic bioactive compounds. The results showed that under the same addition level, the degree of substitution (DS) of modified PG decreased with the extension of the carbon chain in different alkenyl succinic anhydrides, while for the same alkenyl succinic anhydride, the DS increased with higher additive amounts. The higher the DS of modified PG, the more pronounced the effect of pH on the zeta potential. Both OSA-PG and DDSA-PG demonstrated excellent solubility and stability in aqueous environments, whereas ODSA-PG exhibited markedly reduced solubility and stability. Compared to native PG, different hydrophobically modified PG exhibited improved rheological and digestion properties. Among them, DDSA-PG exhibited higher shear stability than OSA-PG, but OSA-PG was more resistant to enzyme degradation. The findings of this study indicate that PG modified with different carbon chain lengths of hydrophobic anhydride groups has great application potential and offers a theoretical basis for the construction of pH-responsive nanocarriers and lipopolysaccharide transport carriers.