A microwave extraction method involves the steps of placing biological material
in an enclosure without any solvent whatsoever and exposing the solvent-free biological
material to microwave radiation to free at least some of the natural product, and
then separating any residual biological material from the extracted natural product.
Additionally, the microwave extraction method involves the steps of applying reduced
pressure in the enclosure during the microwave radiation stage and heating the
enclosure during at least most of the microwave radiation stage to compensate for
the temperature drop resulting from water evaporation from the biological material.