In the case of all alkaloids, gramine and DMT included, they will occur in the plant in the salt form. Purines like ceaffeine don't really count, for you pedants out there. Acidification is recommended as much because water supplies can often be slightly alkaline as it is to improve the alkaloids' solubility in the presence of tannins.
A recent thread suggests that gramine may not be all that toxic but I would still be wary of its headache-causing potential since having got one after munching a load of raw phalaris grass. In that case it could equally have been a coincidence, or due to stress, coffee or nitrates. There are still too many unknowns regarding the effects of gramine and 5-methoxygramine in humans and I think most people would be understandably reluctant to engage in experimentation. The possibility of adverse synergies cannot be discounted and, given the nature of the realms being explored here, fear and uncertainty alone can be uncomfortable travelling companions for the psychonaut, albeit not insurmountably so for a dedicated plant practitioner.