กากกาแฟ extracts were more antimutagenic than their
respective coffee brews against the action of the direct acting
mutagen NPD. Robusta spent coffee was the most protective
sample (up to 35%), while the Arabica spent coffee inhibition
percentage ranged from 12 to 26%.With regard to coffee brews,
Robusta had a protective effect between 20 and 23%, whereas
Arabica coffee brew had the least antimutagenic effect, showing
no significant differences