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Author Topic: Solvent extraction of botanicals  (Read 2959 times)

Offline CKMA

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Solvent extraction of botanicals
« on: 05/02/2015 18:45:12 »
I am looking for a way to extract full spectrum herbs that I grow at home for personal use and I want everything I can possibly get from the plant without the actual plant matter so I can store the extract in the form of a tincture for extended periods.

I have access to raw fresh herbs and a vacuum distillation setup.

I am looking for either a multistep process involving nonpolar, protic, and aprotic solvents through extraction based on increasing polarity

or

A single extraction solvent like maybe a triple extraction with pure acetone..

I lack more advanced knowledge in this subject and did preliminary searches in this forum already.

thanks


 

Offline chiralSPO

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Re: Solvent extraction of botanicals
« Reply #1 on: 05/02/2015 19:02:00 »
The required methods and solvents depend very much on what you are trying to extract, and how pure it needs to be (what do you want to get, and what do you want to exclude?)

Common household solvents (listed from most to least polar) include:

Protic: water>methanol>ethanol>isopropanol
Polar aprotic: acetone>methyl ethyl ketone (MEK)>ethyl acetate (you might also be able to get dichloromethane, dichloroethane or chloroform, but it's probably best to avoid chlorinated solvents)
Nonpolar: toluene, mineral oil, vegetable oil, butane (highly flammable gas that can exist as a liquid when compressed or cooled)

Most of these are flammable and many are toxic. If you plan on ingesting any of your extracts (which could be very dangerous!), I would stick to water, ethanol, ethyl acetate and vegetable oil.

Controlling pH is also very useful for separating ionizable compounds. Salicylic acid (which can be isolated from aspen or willow bark) is soluble in polar aprotic solvents under neutral to acidic conditions, but becomes more soluble in water under basic conditions because it is deprotonated. One can take advantage of this type of manipulation to separate acidic compounds from basic compounds from non-ionizable compounds. Solutions of white vinegar (acetic acid) and baking soda (sodium bicarbonate) should suffice for this. (In a pinch, you can also make acid-base indicator from boiled red cabbage)

Long story short: if you don't know what you are doing, it is best not to play around with chemicals with the intent of ingesting any resulting products or extracts, but you can have a lot of fun isolating essential oils, pigments or other interesting compounds from plants.
 

Offline CKMA

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Re: Solvent extraction of botanicals
« Reply #2 on: 05/02/2015 19:41:04 »
Protic: water>methanol>ethanol>isopropanol
Polar aprotic: acetone>methyl ethyl ketone (MEK)>ethyl acetate (you might also be able to get dichloromethane, dichloroethane or chloroform, but it's probably best to avoid chlorinated solvents)
Nonpolar: toluene, mineral oil, vegetable oil, butane (highly flammable gas that can exist as a liquid when compressed or cooled)

So I understand the dangers of combustion of these solvents and maximum allowable ppm 1500 for acetone and 3000 for methanol as advised for products that we can purchase on shelves...

There is no open flames or any sparks in the area and it is in an open area for distillation. 

I could easily match up what to use and how to use it .. if we understood what was in the plant that I was trying to extract while the plant shows significant results via clinical studies (when consumed raw) for what I need it for .. the mechanism and the chemicals involved are not well understood.

As of now I consume the plant whole after growing it in a high pressure aquaponic aeroponic system.  but need portability and the ability to hold the fresh plant properties for a long duration of time ... I enjoy doing things like going for motorcycle rides in the painted desert and stuff... as I can not bring my system with me on the back of a motorcycle I need to extract and store the plant... there is no alternative through regular medicine for this plant I consume ... but it works insanely well for preventing what it prevents.... in addition an extraction in the TCM manual is not as potent as raw..  the glycerin extraction is lame and so is the ethyl water... so Ive done about a month of research on botanical extraction and how it works ... it seems like I need full plant extract to get the same effects thus I need a full spectrum extraction...

With that being said I do plan on using high grade solvents in a vacuum distillation apparatus.... starting with non-polar solvents moving to increasingly polar solvents either in 3 or 5 steps N-heptane -> acetone -> methanol or an addition of two additional solvents in between N-heptane and acetone ... and acetone and methanol.  My budget is around 5000$

you would be correct to assume that I do not understand if these chemicals with alter the natural components because I do not nor does really anyone I can get a hold of understand what these components are.

I would like to know of alternatives to this using fewer solvents such as a triple extraction with methanol as I have read that it can potentially extract non -polar and polar chemicals from plants... and that probably would limit the risk of creating something funky.

Co2 subcritical and supercritical is out of the question due to cost ...

Maybe this will help with the question I am asking.

Thank you again.
 

Offline chiralSPO

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Re: Solvent extraction of botanicals
« Reply #3 on: 05/02/2015 19:53:50 »
May I ask what the plant is? Do you have any idea what type of compounds you are trying to extract?
 

Offline CKMA

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Re: Solvent extraction of botanicals
« Reply #4 on: 05/02/2015 19:59:47 »
May I ask what the plant is? Do you have any idea what type of compounds you are trying to extract?

no one that ive been able to ask really understands what it is and research is nothing... the plant is kanehohana flower ... I had some while in hawaii brought back seeds and grow it for myself...
 

Offline CliffordK

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Re: Solvent extraction of botanicals
« Reply #5 on: 05/02/2015 22:54:41 »
Is that Stenogyne kanehoana?  It is apparently an endangered species. 



How long have you had the seeds?  If you've had them since before the year 2000, then you might consider sharing some seeds with the University of Hawaii.
 

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Re: Solvent extraction of botanicals
« Reply #5 on: 05/02/2015 22:54:41 »

 

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