Don't want to sound like the PC police but personally I would have chosen another verb for the title. The origins of the word "denigrate" are not particularly great:
1520s, from Latin denigratus, past participle of denigrare "to blacken, defame," from de- "completely" (see de-) + nigr-, stem of niger "black" (see Negro).
It's not an explicitly racist term. Just like "blacklist" or the "pot calling the kettle black". Black has a negative connotation that is separate from race.
So many, many linguistic troubles descend from some blind idiots deciding to call pink and brown people "white" and "black," and subsequent assumptions that all white/black color metaphors must therefore be racial.
1520s, from Latin denigratus, past participle of denigrare "to blacken, defame," from de- "completely" (see de-) + nigr-, stem of niger "black" (see Negro).
(source: http://www.etymonline.com/index.php?allowed_in_frame=0&searc...)