Kavion123
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CWE of Piperidine
Can I perform a cold water extraction to grab piperidine from black pepper? I know piperine, the alkaloid, is not so water-soluble at 278K.
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Bert
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Thread Moved
12-1-2015 at 19:33 |
Praxichys
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The point of extracting using a nonpolar solvent is so that most of the water soluble garbage is left behind. You might be able to extract
something from pepper with cold water, but it will probably be a bunch of starchy, salty crap.
An acid/base extraction with would be far better. Soak or macerate the pepper in weak acid to generate the highly soluble salt of the alkaloids, then
filter. Add a base until the solution is basic, which reduces the water solubility of the alkaloid. Extract the solution a few times with something
nonpolar and volitile. Take your pick - xylenes, toluene, lighter fluid, camp fuel, chloroform, dichloromethane, ethyl acetate, diethyl ether, light
naphtha...
Dry off the solvent and you are left with alkaloids, because of their ability to change solubility drastically based on pH.
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Kavion123
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Quote: Originally posted by Praxichys  | The point of extracting using a nonpolar solvent is so that most of the water soluble garbage is left behind. You might be able to extract
something from pepper with cold water, but it will probably be a bunch of starchy, salty crap.
An acid/base extraction with would be far better. Soak or macerate the pepper in weak acid to generate the highly soluble salt of the alkaloids, then
filter. Add a base until the solution is basic, which reduces the water solubility of the alkaloid. Extract the solution a few times with something
nonpolar and volitile. Take your pick - xylenes, toluene, lighter fluid, camp fuel, chloroform, dichloromethane, ethyl acetate, diethyl ether, light
naphtha...
Dry off the solvent and you are left with alkaloids, because of their ability to change solubility drastically based on pH. |
Thank you.
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Nicodem
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Piperidine is not contained in relevant amounts in pepper (Duke's phytochemical database lists it as a component, but does not give the content). The
only thing easily extractable from pepper is piperine.
| Quote: Originally posted by Praxichys | | An acid/base extraction with would be far better. Soak or macerate the pepper in weak acid to generate the highly soluble salt of the alkaloids, then
filter. |
Piperidine partitions very well into water, basic or not, so that an acid/base extraction would not be particularly successful.
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unionised
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The stuff that makes pepper "peppery" is piperine.
Since the nitrogen atom in piperine is in an amide, rather than an amine, it's not going to change solubility very much with pH unless you make the
conditions so drastic they hydrolyse it.
A "classic" alkaloid extraction won't work for piperine.
It barely works for piperidine (because it's very water soluble, even as the free base) and there's not much of it there anyway.
What are you actually trying to do?
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Bot0nist
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I was able to extract piperine from black pepper here using refluxing isopropyl and a bit of workup.
Piperine from black peppercorn, 91% isopropyl alcohol.
[Edited on 14-1-2015 by Bot0nist]
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