A typical alkaloid extraction could be used to isolate the alkaloids, although isolating just the DMT (which is what you seem to be implying) would require a further chromatography step most likely.
1)Grind up plant material
2)Extract alkaloids (couple of choices here)
a)soxhlet it
b)relux in polar solvent with stirring
c)soak for about a week at a time with some stirring
These should all be done 2-3X.
3)(optional) defat with similar volume of non-polar solvent. Just bring the pH to 10.68 or somewhere near there (at pH 6.68 and above, 99% of the DMT is protonated (ie. charged) since it is 2 pH units below its pKa, which from memory is 8.68) Once the pH is at 6.68, add a similar volume of non-polar solvent (ie. naptha, DCM) in a sep funnel and shake, then discard the polar solvent.
3a (optional) boil up the aqueous extract with activated carbon...this is rarely done in literature because the compound of interest is often just extracted and then chromatographed...if you are having troubles getting as pure a product as you want, you
might try adding a small amount of activated carbon to get rid of some of the extra heavier compounds...
4) Transfer DMT to organic (non-polar) solvent: bring the pH of the polar (aqueous) solution up to 10.68, by which point 99% of the DMT will be in deprotonated (neutral) form. Shake w/ slightly less than equal volume of non-polar/organic solvent. Do this three times, combine the organic extracts, keep them.
5)Remove the solvent either by stripping under vacuum (distillation setup, vacuum is not always used) or simply evaporating (don't do this where you need to breathe, and don't do this if you can do anything else...tough on the environment...
6) You should be left with some goo or crystals....multiple runs through the acid-base transfers may lead to a purer product if you like, but keep in mind that you are likely to lose some product in the process...
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