Structural and functional variations of octenyl succinylated clustered amylopectin produced by distinctive glycogen branching enzymes.

Unlabelled: Clustered amylopectins (CAPs) were produced using recombinant glycogen branching enzymes from K12 (EcGBE) and (VvGBE). The CAPs were esterified with octenyl succinic anhydride (OSA), introducing novel functional characteristics. Vv-CAP demonstrated a reduced apparent molecular weight and a higher prevalence of both short (degree of polymerization (DP) ≤ 5, 13.3%) and medium branches (5 < DP ≤ 12, 58.2%) compared to Ec-CAP. FT-IR spectra confirmed the successful esterification of CAPs with OSA. H-NMR analysis showed the degree of substitution (DS) for OSA-CAPs varied based on the CAP to OSA ratio (DS 0.021-0.058 for Ec-CAP and 0.011-0.066 for Vv-CAP). Esterification with OSA on shortened branches resulted in a slower digestion rate and increased resistant starch proportion. Additionally, this process enhanced the emulsifying properties of CAPs and improved the aqueous solubility of puerarin. OSA-modified CAPs are promising for pharmaceutical applications.

Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-025-01892-1.