tl;dr: An Aurelia (pump) extracted more chlorogenic acids than an Athena (lever); Arabica has more chlorogenic acids than Robusta.

Importance of Espresso Coffee Machine Parameters on the Extraction of Chlorogenic Acids in a Certified Italian Espresso by Using SPE-HPLC-DAD
Giovanni Caprioli, Manuela Cortese, Luigi Odello, Massimo Ricciutelli, Gianni Sagratini, Giacomo Tomassoni, Elisabetta Torregiani, Sauro Vittori
http://www.ccsenet.org/journal/index.ph ... view/24563

I found the article through this neat (I think) 2014 book: Coffee in Health and Disease Prevention - Victor R. Preedy (Google books link so you can preview it - I was able to read at least the two chapters below)
https://books.google.ca/books?id=cFECBA ... navlinks_s

Chapter 27: Physicochemical Characteristics of Roasted Coffee - relates qualities of coffee to measurable chemicals (if you have a lab )
Chapter 28: Espresso machines and coffee composition - "The usual espresso machine settings (92C and 9 bar) seems to be the best choice for extraction of caffeine, trigonelline, and nicotinic acid, especially from Robusta blend."

Not something to be particularly worried about, though. http://examine.com/supplements/Chlorogenic+Acid/
You'd still need 3 cups of either to hit a useful dose as used in the studies...

I can see why you might think of CGA's in a health context - I should have been clearer, as that wasn't why I posted. CGA's are not very pleasant to taste - arguably, the better the roaster, the better he/she reacts away the CGA's in his/her greens; and, the 'better' tasting the coffee, the less CGA's there are in that coffee (this is a gross over-simplification; obviously CGA's are not the only component of 'bad' taste in coffee).

Thus, I found it interesting that in controlled conditions, a lever machine produced less CGA's than a pump machine. People sometimes talk (anecdotally) about how lever machines attenuate taste extremes compared to pump machines; and that it is difficult to produce a sink shot with a commercial spring lever. The paper provides objective evidence to support those ideas (support, not prove, but support none-the-less).

Ah, thanks for clarifying. I did think based on the title and other comment it was health related.
Taste evidence is certainly very interesting and helps us understand more about what's going on!