Hi all, there have been some challenges with regards to genomic DNA extraction directly from fermented milk samples. Any input with knowledge on troubleshooting would be appreciated. I have been isolating DNA directly from fermented milk, samples using the conventional Phenol Chloroform method. However, despite having relatively high concentrations and purity the samples are showing smears when being run on 0.8% agarose gel. Images will be attached to show the gels. The same method was used on 2 separate isolates obtained from the milk samples and here single bands were obtained (AV1 IS1 and MV1 IS1). It is specifically challenging with isolating directly from the milk samples itself. Please can you assist.
Hello dears, I would like to invite you to read my ebook "The fantastic microbiological world" for free on Amazon (https://www.amazon.com.br/dp/B0CF1VKKK8)
Brynita Pillay It looks like the fermented milk has high nucleases activity. See Koupal, A., and R. H. Deibel. "Rapid qualitative method for detecting staphylococcal nuclease in foods." Applied and environmental microbiology 35.6 (1978): 1193-1197.
In general, magnetic particles are usually applied for milk DNA with good success, but inactivation of nucleases at very first step of DNA isolation would be the most important.
Perhaps, this work will be useful for you:
L. Quigley, O. O’Sullivan, T.P. Beresford, R. Paul Ross, G.F. Fitzgerald, P.D. Cotter, A comparison of methods used to extract bacterial DNA from raw milk and raw milk cheese, Journal of Applied Microbiology, Volume 113, Issue 1, 1 July 2012, Pages 96–105, https://doi.org/10.1111/j.1365-2672.2012.05294.x
- Badges
- Science method