Under the action of glutathione-transferase, the reduced glutathione energy is combined with peroxide and free radicals to counteract the destruction of sulfhydryl by an oxidant, to protect the protein containing sulfhydryl in the cell membrane and the enzyme-containing sulfhydryl, and to counteract the damage of free radicals to important organs. Glutathione is widely found in plant and animal cells, with more content in the liver and lens. Can now be produced by chemical synthesis or fermentation.