This question is about keywords in HTML.
Which of the following cases is more favorable from an SEO point of view?
Arizona State University, Education
Arizona, State, University, Education
Major search engines do not use the meta keywords tag, for example Google. I'm presuming you're talking about keywords in the meta tag, because you used that tag on the question.
The logical way to structure keywords is to use individual words (i.e. your second option).
However, meta keywords have zero effect on SEO in Google or Bing so your best strategy is to ignore them. Don't use the tag at all or waste any more time thinking about meta keywords.