Optimization of liver glycogen extraction when considering the fine molecular structure

Abstract

Liver glycogen is a branched glucose polymer that functions as a blood-sugar buffer in animals. Previous studies have shown that glycogen's molecular structure affects its properties. This makes it important to develop a technique that extracts and purifies a representative sample of glycogen. Here we aim to optimize the sucrose density gradient centrifugation method for preserving glycogen's molecular structure by varying the density of the sucrose solution. The preservation of glycogen's structure involves: 1) minimizing molecular damage and 2) obtaining a structurally representative sample of glycogen. The addition of a 10-minute boiling step was also tested as a means for denaturing any glycogen degrading enzymes. Lower sucrose concentrations and the introduction of the boiling step were shown to be beneficial in obtaining a more structurally representative sample, with the preservation of smaller glycogen particles and decreased glycogen chain degradation.

Keywords: Glycogen; Glycogen extraction; Molecular structure; Size exclusion chromatography; Sucrose density gradient centrifugation.