According to the meaning of the question, Li Shengxue used 100 kg of Ganoderma lucidum to extract the essence, so:

The original weight of Ganoderma lucidum is known as 100 kg.

It is known that the weight ratio of the extracted Ganoderma lucidum essence to the original Ganoderma lucidum is 0.0 1.

According to the proportional relationship, the weight of the extracted Ganoderma lucidum essence can be calculated:

100 USD times 0.0 1 = 1 kg USD.

Therefore, Li Shengxue used 100 kg of ganoderma lucidum to extract 1 kg of ganoderma lucidum essence.