2-Pentanone or methyl propyl ketone (MPK) is a ketone and solvent of minor importance. It is comparable to methyl ethyl ketone, but has a lower solvency and is more expensive.<ref>Template:Citation</ref> It occurs naturally in Nicotiana tabacum (Tobacco)<ref>Template:Citation</ref> and blue cheese as a metabolic product of Penicillium mold growth.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>