Soil was incubated in 2% CTAB overnight at 37C. I spun the samples down and took the supernatant directly into phenol:chloroform:isoamyl alcohol 25:24:1. The Icelandic soils turned pink and purple, while the control soil from Indiana stayed colorless. After a subsequent chloroform purification step the color was gone. I got good DNA yield from one of the two samples. Any idea why the phenol turned pink and purple? Is there a way to prevent this, and should I even try given that the purification worked?
Thanks for the help!