What is the significance of "eye of newt and toe of frog" in the witches' potion in Macbeth?

In Macbeth, the ingredients "eye of newt and toe of frog" in the witches' potion symbolize the supernatural and dark nature of their magic. These ingredients are used to create a sense of mystery and foreboding, emphasizing the witches' connection to the supernatural world and their ability to manipulate fate.