Liver subcellular fractions (S9 or Microsomes) refer to different organelles and structures that can be isolated from liver tissues. The technique involves breaking down the liver cells through tissue homogenization and further separating their components based on their size, density, and other physical properties. The resulting fraction represents distinct cellular compartments, each enriched with specific organelles and biomolecules. These fractions are valuable for studying the functions and activities of individual cellular components of the liver.