Humic acids and DNA purification

Paul A. Vescio vescip at
Fri Sep 9 04:17:47 EST 1994

In Article <34n4i3$a26 at>, <Herveg at> wrote:
>Miguel Villegas <hcampos at>
>>Some of these waters
>>have high
>>contents of dissolved humic acids (H.A.), polimers of highly
>>refractary organic 
>Humic acids! I learn the existence of these compounds from Hagelberg E.:
>Humic acids contaminate some archaeological bones ... , they are extracted
>together with the DNA! So when regions of mtDNA are submitted to PCR
>amplification for haplotype determination, they inhibit the DNA Pol!
>How can we purify this DNA to avoid this kind of contamination, easy to
>recognize because the DNA solution is colored in brown!
>The purification technology requires some knowledge about those compounds,
>What are they, what property can be used to separate them from DNA?
Try adding Polyvinylpolypyrrolidone to your lysed cell/soil mixture.  The
PVPP absorbs quit a few of the humics.  also try an ammonium acetate/CTAB
precipitation to get rid of them.   Give me an email buzz and maybe I can
give a few more suggestions.  I have been working on DNA extractions from
sediments for about 2.5 years with some pretty good results.
Paul A. Vescio                      
Biology Dept.
Rensselaer Polytechnic Institute

!!New York Rangers  Stanley Cup Champions 1994!! 

More information about the Microbio mailing list