Resistant starch type 1 and 2 macromolecules from giant swamp taro (Cyrtosperma merkusii): A potential solution for lipid metabolism-regulating strategies

Abstract

Liver lipid management is a recognized strategy for the treatment and prevention of degenerative diseases and metabolic syndrome. Giant swamp taro (GST) starches are biomolecules extracted from GST (Cyrtosperma merkusii) sourced from Sangihe Island, North Sulawesi, Indonesia. GST contains naturally occurring resistant starch types 1 and 2. GST starch was characterized by observing its structural compositions, crystallinity structure, and granule microstructure using Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy, respectively, which confirmed the extracted starch macromolecule and natural presence of resistant starch in GST. GST starch was fed to male Sprague-Dawley rats (Rattus norvegicus) induced with a high-fat diet (HFD). These rats were compared to a normal group fed a ruminant feed, a negative control group fed only an HFD, a group administered glibenclamide, and a group administered simvastatin. The results showed that GST starch has a positive impact on oxidative stress and lipid metabolism regulation. In terms of hepatoprotective activity, GST was more closely associated with lipid regulation than with sugar metabolism, as indicated by its stronger correlation with simvastatin than with glibenclamide. The resistant starch in GST is likely involved in the regulation of gut microbiota composition; however, this mechanism has yet to be confirmed.

Keywords: Cyrtosperma merkusii; Giant swamp taro; Lipid metabolism; Resistant starch.