Extracting alkaloids from
Instructions for purifying alkaloids from
Tricocereus cacti. This
is a general method for concentrating alkaloids, with emphasis on
mescaline, but which may be adapted to
other plants and alkaloids. It
requires that the alkaloids be relatively basic and that the base form be
less soluble in water. So it would work well for
DMT, but not
or caffeine for example.
The principle of alkaloid purification is to obtain from a plant only that
fraction which is basic. This is achieved by a double layer extraction,
relying on the principle that amines (as opposed to most of the other
compounds in a plant) are soluble in acidic (the salt form) but insoluble
in basic (the basic form) aqueous solution. However, the basic form is
soluble in non-polar organic solvents whereas the acidic/salt form is not.
Thus, by varying the pH, alkaloids can be taken from aqueous solution to
organic solution or vice-versa, leaving behind other materials.
Some chemicals and equipment are important for successful extraction of
alkaloids from cactus. The chemicals include methanol, dichloromethane or
chloroform, sodium hydroxide and hydrochloric acid. The equipment includes
a distillation apparatus, a separating funnel, and various beakers and
containers, pH tester, and filter. Alternatives can be found for each of
- Slice and dry the cactus. I haven't worked out the best way to do this;
no matter how I do it, I am always afraid that I am destroying the
alkaloids. In general, what seems to work is to slice it thinly, and
run hot air over it overnight. The more water which can be removed from
the cactus at this stage, the easier the process will be. [Another
possibility might be to use a drying agent such as Calcium Chloride
Preservation" section of the Magic Mushroom Growers Guide for more
- Pulverise the dried cactus. I have tried using a blender, and it seems
to work moderately well. The cactus is tough so you will have to be
patient. The finer the grinding, the better the extraction.
- Extract dried cactus with methanol. Ideally this is done hot using
solvent-extraction apparatus (soxhlet). Various makeshift methods may
suffice for a hot extraction, but I have generally merely soaked the
stuff for up to a week, cold. Ideally this step should be done three
times, and the extracts concentrated. I have done it once for a week,
and then washed out the absorbed methanol with fresh methanol once or
twice over an hour or two. What you should end up with, after filtering
out the bulk of the cactus, is a green methanol extract. Ethanol or
acetone could be substituted for methanol, but neither of these is
quite as effective. It is generally desirable to use several times the
weight of the dried cactus for the methanol extraction, or at least
enough to cover it well in a container.
- Remove the methanol to leave just an extract residue. This is best done
using vacuum distillation, but can be done using atmospheric
distillation, to recover the solvent. If you don't mind losing several
litres of methanol, you can merely boil the stuff into the atmosphere;
just avoid starting a fire. Always no matter what use boiling
chips (porcelain) to promote even boiling. Methanol superboils easily,
as I have found :-(. Once most of the methanol is removed, you will be
left with a hundred ml or so of watery, methanoly, green slime. If it
weren't for the methanol and the bad taste, this could be consumed at
this point. In general, I would say that it may be worth your while
going to the next stage if you can manage it.
- Add dilute hydrochloric acid. Sulfuric acid, etc. could be used
instead, but I like to use HCl and NaOH, because the product is NaCl,
which is of no consequence if it contaminates anything. HCl is not as
oxidising as H2SO4. The HCl
should be less than 1M, but not weaker than
0.1M (pH 0-1). Add a few times the reduced volume of liquid - e.g.
take the stuff to 400 ml from 100 ml, etc. One good idea is to let the
bulk cactus residue (post methanol) dry, and then soak it for a few
hours in the acid you are going to use to add at this point. This will
extract the last of the alkaloids. Unfortunately, cactus being what it
is, will swell enormously, and removing the HCl is tricky. I have
resorted to large quantities of HCl and a kind of press to squeeze out
the acid from the bulk residue. This acid should then be filtered, and
added to the methanol extract residue as above.
- (optional) The stuff at this point will be a bit of a mess. Adding
activated charcoal and boiling gently for 10 minutes will help to
congeal the chlorophyll etc. which is gumming up the stuff. Do not add
too much charcoal - less than a gram should be plenty. Too much will
absorb alkaloids. Don't use burnt wood, burnt toast, etc - get the
proper stuff from the local pharmacist. Performing this step will make
the next stages considerably easier.
- Filter the HCl extract. This will remove a proportion of the gunge.
This will be easier if charcoal was used. The more gunge that can be
removed at this stage, the better. Washing the residue with fresh HCl
before discarding, and adding this to the rest will ensure no loss of
- Carefully basify the HCl solution with NaOH. I tend to use around a 5M
solution for this, which is OK as long as you stir as it reacts. Take
it well above pH 7. You should get white clouds of alkaloids forming in
the solution, and the whole will become turbid as some of the acid
soluble components precipitate. Ammonia or KOH should work for this
purpose as well. I have had some difficulty with ammonia not being
quite basic enough in other systems.
- Add dichloromethane (or chloroform); be generous with the quantities if
possible. Ideally, one would like to extract into CH2Cl2 3 times with
equal volumes, but the amount of solvents gets huge. Ether is not all
that good with mescaline extraction, I believe, even though it is
easier to separate from water. CH2Cl2 is handy because it has a very
low boiling point. It is at this point in the whole operation that the
most care and patience is necessary. A separating funnel is really a
must - one could plausibly separate the layers with a very tall thin
jar and a syringe, but this would be difficult. Ideally, the basic
solution and the CH2Cl2 will separate into 2 nice layers, the lower one
(organic) containing the alkaloids. Unfortunately, while this is not
difficult with most plants, it is very difficult with cactus extracts
because the cacti contain so much resinous junk and natural surfactents
(to retain water). The best way I have found to separate the layers
once you have shaken them together is to add plenty of salt (NaCl) to
the water/base layer. This is excellent for breaking the emulsions
which form. Be prepared to use large quantities of salt.
- Separate dichloromethane layer from mixture and put aside. Repeat steps
9-10 a few times: once is insufficient, three is good, four is
excessive. Combine all the dichloromethane extracts together. This
should be a slightly green solution. It will contain a bit of water,
- Backwash the dichloromethane once with a solution of salt and NaOH
(dilute). This will clean up the last of the junk from the organic
solution. Separate the layers as before and discard all aqueous
- Distill off the dichloromethane (or allow to escape to the atmosphere
if you are rich and don't like the ozone layer). I have found that once
you are down to maybe 20 ml of residue, the best option is to place the
remainder in a petri dish (or some flat dish you are going to store it
on) and hitting it with a hairdryer to remove any last CH2Cl2 and
water. You should be left with a small quantity of moderately pure
alkaloids. This can be easily consumed by dissolving in vodka, e.g., or
should be stable for extended periods if refrigerated, frozen, kept
airtight and away from moisture. Do not expect more than a 50% yield
the first time you try this: theoretically if everything is done
properly, the yield should approach 100%, but this is rarely the case.
Subject: Re: Extracting alkaloids from Tricocereus cacti.
I've had a quick scan through that post, and it seems he's been pretty
complete in his description. I can add the following information:
- The initial extraction is very important. You only have as much
alkaloid to play with as you extract at this point. Similarly, the more
gunk you extract at this stage, the more you'll have to eliminate.
Methanol is used because it's not too polar or non-polar, and it
penetrates cell walls and membranes quite effectively. Acetone would be
as effective, but it seems to pull much more gunk out along with it,
and for this reason should probably be avoided. Also note that the
better your mechanical mulching process is, the more effective the
extraction will be. Also, note that a hot solvent extraction under
reflux conditions, or using a soxhlet would be more effective, but bear
in mind that some alkaloids may decompose with heat - it's probably
worthwhile checking the physical characteristics of the alkaloid in
question in your handy Merck index or CRC handbook.
- With respect to the degree of acidity and basicity necessary for the
extraction, this can only really be found by trial and error.
Insufficient difference from neutrality will cause insufficient
separation, extremes of pH (particulary too basic) may cause alkaloids
to be degraded or other nasty things to happen. Also note that other
compounds present may act as buffers - be sure to stir well, and
measure the pH using indicator paper or somesuch.
- The final product is a free base. Usually it's unneccessary to go
further than this. Forming a salt can be tricky, and would also be
wasteful. If you're ingesting the product orally, then it'll salt
adequately with the HCl in your stomach. If you're concerned with
oxidation by the air, well, use your better judgement (are you really
going to wait that long before eating the stuff). Of course, if it's
DMT and you're going to smoke it, forming the salt is a waste of time.
Hope that's helpful.
Subject: Re: Extracting alkaloids from Tricocereus cacti.
One other question though which is on "backwashing"... what
exactly is this procedure?
Once you've extracted the goodies into the solvent layer, you attempt to
remove any remaining non-alkaloid gunk that may have come along with it.
So you wash the extract with basified water, which forms another layer
which you discard. Jez describes this in the procedure. It's not always
necessary, but once you've got that far, it's usually not difficult to do
(i.e. you've got the layers to separate successfully once already)
The Sputnik Extraction Pages.
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