how to remove content of glucomannan in the Amorphophallus tubers of which will be isolated DNA. I've tried to do isolation using CTAB agent, and when do elektrophoresis, no DNA is visible. Any suggestions?
It's possible to remove glucomannan using mannanase. This plant contains high amont of mannan and will make difficult to exact the DNA from that plant. I think you can try it, but not sure.
It might not work but the combined use of PVP, CTAB Buffer, 2-mercaptoethanol and long incubation durations gave me DNA with good purity from a woody plant... Good luck !
on the protocol which I profess, the maximum incubation period is 60 minutes, 65 degrees Celsius. so based on your experience how long should I do incubation?
I've already tried 2 hours but it didn't improve much isolation... Now I use 1 hour at 60°C (in some protocols the time is 15 min that's why i told you long incubations). So if you want to remove glucomannan, you could increase salt concentration of CTAB buffer, or increase PVP concentration. Here is a link for a publication of modified CTAB extraction: http://www.springerlink.com/content/w450752253324r4j/