Dune is an allegory of the world we live in... our present day universe. It is speaking about things that are trans-human. The spice "melange" is people... human beings. The sand worms are the serpent, as spoken about in the adam and eve story. You see, the serpent is composed of, and wears, human beings like skin and clothing. The serpent also sheds its skin in continuous fashion, and this is why "melange" is produced. "Melange" is the life force essence, contained within human beings, which brings about transcendental power to the space guild.

Humans are farmed by advanced alien beings. Entire civilizations are powered by the output from the earth.

Let me ask you this... If the world is energy rather than physical matter, where do you think fusion energy from the sun comes from?

Just FYI, the ring in Lord of the Rings is a wedding ring.