Sciencemadness Discussion Board

Extraction of coniine.

Sean Ambrose - 25-5-2004 at 02:42

hello

The Coniine is a violent poison extracted from the Hemlock. it is an Alkaloid.
It is like curar because it paralyze the nervous system. It was used in the Antiquity to kill the bad politician.(Socrate have drunk the Hemlock). The Hemlock is a very toxic common plant in Europe :) but less in America :(
.
Does someone knows how to extract Coniine from Hemlock ? :D


Thank You.

BromicAcid - 25-5-2004 at 15:22

The extraction of alkaloids from natural sources is well covered both on the internet and in books as well. Although extracting Coniine might have its own specific difficulties expecially if you want an expecially pure sample, it still follows the usual protocol for extracting alkaloids. So put some effort into it before saying that extracting the alkaloid with an acid and precipitating with a base is information that cannot be found anywhere and find that information for yourself.

FritzHaber - 25-5-2004 at 17:46

Quote:
Originally posted by Sean Ambrose
hello

The Coniine is a violent poison extracted from the Hemlock. it is an Alkaloid.
It is like curar because it paralyze the nervous system. It was used in the Antiquity to kill the bad politician.(Socrate have drunk the Hemlock). The Hemlock is a very toxic common plant in Europe :) but less in America :(
.
Does someone knows how to extract Coniine from Hemlock ? :D


Thank You.

1) coniine isn't THAT toxic...compare its LD (ca. 400-600mg per os) to those of f.e. colchicine (~20mg), or aconitine (5-10mg). both of latter two are aboundant in continental europe flora (Colchicum autumnalis and the Wolfsbane, Aconitum napelus).

2) however, its extraction from the raw material is carried out by the means of steam-distillation from fresh harvested plant segments, and alcalised with addition of caustic soda or lime prior to distillation, just as in the case of nicotine.
the collected distillate is then cooled, made acidic by carefull titration with dilute sulfuric acid, the volume of solution is reduced by vacuum evaporation to about a 1/3 - 1/4 of original volume. this concentrated solution is then cooled, its pH adjusted to 9,5 -10,0 (with 4M NaOH), the solution is further saturated with NaCl, cooled to a T below 10°C and extracted by 5 portions of ether.
the ether extracts are colected, dryed with anhydrous Na2CO3, the ether is then ditilled off an steambath.
you should obtain majority of the original coniine as a stinky oil.

Sean Ambrose - 25-5-2004 at 23:54

Is it possible to replace the ether by 95 %denatured ethylic alcohol?


I have watch the recipes for the extraction of the coca paste from the coca plants and they use fisrt an caustic solution that they add to a bath of water. they let the plants in this bath for several days and then they extract alkaloids from the bath with kerosene.

they keep the alkaloids by changing the PH of the solution with sulfuric acid.

this method seem to be more simple than the method with ether. does it work well for the Coniine ?

FritzHaber - 26-5-2004 at 12:23

..."I have watch the recipes for the extraction of the coca paste from the coca plants and they use fisrt an caustic solution that they add to a bath of water. they let the plants in this bath for several days and then they extract alkaloids from the bath with kerosene.

they keep the alkaloids by changing the PH of the solution with sulfuric acid.

this method seem to be more simple than the method with ether. does it work well for the Coniine "...
--principally yes, but since coniine free base is too much volatile, this method will provide very poor yields imo.

PHILOU Zrealone - 26-5-2004 at 15:20

You can reinvent the wheel but for alkaloids they have sometimes very particular properties that are used for isolation...know that when you have plant juice ...it contains more than 1000 molecules and you try to pick one or two in the lot...by playing with pH and the amphiphilic character of alkaloids ...you are able to restrain the amount of molecules you have to a few dozens...the the good knowledge of the chemical properties of the interest molecule allows you to isolate it...usually several chromatography must be used ...except if you follow a very good recipe.

And NO :mad: ethanol can't be used in place of ether to make a biphasic extraction...because ethanol is amphiphilic and the role of the solvent si to dissolve selectively at a given pH the molecular form or the ionised form of the alkaloid....most extractions of organic acid or bases you have synthetised...follow the principe:
Acid + organic acid --> soluble in organic phase (molecular form)
Base + organic acid --> salt of acid soluble in water (anionic form)

Base + organic base --> soluble in organic phase (molecular form)
Acid + organic vase --> salt of base soluble in water (cationic form)

Of course ethanol can be used to extract all polar and moderately polar molecules + some lipids.

In isolation labs we use various washes ...
petroleum ether
n-hexan (apolar)
ether
Dichloromethane
ethanol
methanol
water

Now note that it is false assumption that all alkaloïds are basic and display alkaline properties...the only similitude alkaloids have are that they display at least a N (nitrogen) atom and give rise to physiological effect.They have moderate molecular size <1000 g/mol).

:):D;):cool:

happycamper723 - 23-4-2012 at 15:41

Quote: Originally posted by FritzHaber  
Quote:
Originally posted by Sean Ambrose
hello

The Coniine is a violent poison extracted from the Hemlock. it is an Alkaloid.
It is like curar because it paralyze the nervous system. It was used in the Antiquity to kill the bad politician.(Socrate have drunk the Hemlock). The Hemlock is a very toxic common plant in Europe :) but less in America :(
.
Does someone knows how to extract Coniine from Hemlock ? :D


Thank You.

1) coniine isn't THAT toxic...compare its LD (ca. 400-600mg per os) to those of f.e. colchicine (~20mg), or aconitine (5-10mg). both of latter two are aboundant in continental europe flora (Colchicum autumnalis and the Wolfsbane, Aconitum napelus).

2) however, its extraction from the raw material is carried out by the means of steam-distillation from fresh harvested plant segments, and alcalised with addition of caustic soda or lime prior to distillation, just as in the case of nicotine.
the collected distillate is then cooled, made acidic by carefull titration with dilute sulfuric acid, the volume of solution is reduced by vacuum evaporation to about a 1/3 - 1/4 of original volume. this concentrated solution is then cooled, its pH adjusted to 9,5 -10,0 (with 4M NaOH), the solution is further saturated with NaCl, cooled to a T below 10°C and extracted by 5 portions of ether.
the ether extracts are colected, dryed with anhydrous Na2CO3, the ether is then ditilled off an steambath.
you should obtain majority of the original coniine as a stinky oil.


Does sulfuric acid have to be used, or could any acid be used?