If the cacti is fresh one could possibly benefit from freezing the speciment and thawing so as to rupture the cell structure ,thus releasing more.
While you are at it ,and you are in a mood for experimenting may i propose a small extra experimentation (heh for the ones that know me one can say im kinda proposing my experimental agenda
) ?
Mescaline in its hydrochloride salt is insoluble (and from what i hear other cacti alkaloids might be) in acetone.So i was thinking: If one is willing to go through an A/B with bases and non polar solvents -which for some can pose problems- why not try something else. You are going to make a tar/taffy eitherway.First of all while on the final evaporation add a small amount of HCl solution and mix to convert to HCl salts.Then try dissolving it in a minimum amount of anhydrous* acetone so that all gets dissolved, propably heat it up if the tar doesnt dissolve nicely and put it in the fridge overnight to see if anything precipitates.One could also try the freezer ,acetone will not freeze but this will drastically even more drop its solubility. If it doesnt work, well evaporate to dryness and proceed as planed. If it works, see where the precipitate gets you. In this case it would be more concentrated than the resin talked about here, of course not as pure as the one an experimenter will receive after multiple acetone washes and MEK recrystalisations but still : quite of an easy step forward.
For the time being i dont have the resources and time to experiment myself ,but i am throwing the idea on the table both for me to remember in the future and for any other who might want to give this a go.
*One can dry acetone with Epsom salts: cook them in oven to ensure they are anhydrous ,i think methods are described in the forum , and add in the sealed jar of acetone. This will ensure that the acetone used will not contain any water that could dissolve mescaline salts in it. Following this, the procedures would be best to be in sealed vessels and exposed to open air as little as possible so as not to draw any water in since acetone is hydroscopic.