Using ChatGPT API for Automated Keyword Extraction from Academic Textbooks?

Has anyone using ChatGPT for automated keyword extraction from academic textbooks? In some keywords are bolded, but in some cases they are not, and I was curious if one could build a tool that would reliably automate this so one gets a sequential layout of the key technical terms or unique keywords through a long academic textbook such as in Chemistry or other STEM fields.

Sounds simple enough

What keywords from what paper?

If something broader, specify precisely what you would consider a keyword and not

Provide example

Once the definition of what you want is clear, its straightforward