1. A method for increasing oxygen transport function of a hemoglobin-based blood substitute, comprising administering a phthalide
compound to a subject in need thereof, wherein the phthalide compound increases oxygen release efficiency of the hemoglobin-based
blood substitute, wherein the phthalide compound is selected from the group consisting of Z-butylidenephthalide, Z-ligustilide,
senkyunolide A, senkyunolide H, senkyunolide I, senkyunolide F, E-butylidenephthalide, E-ligustilide, 3-butylphthalide, 3-butylidene-4-hydrophthalide,
6,7-dihydroxligustilide and 6,7-epoxyligustilide.