After being removed of contaminants, RWG was defatted with
n-hexane until the supernatant was colourless, and then the resulting
DWG was consecutively air-dried at room temperature, removed
of the detached fine debris by sieving through a 60-mesh
screen, and milled by a laboratory hammer mill to a fineness of
100-mesh. The DWGF was kept in sealed bags at 4 C until use.