Sciencemadness Discussion Board

Chili peper extraction

NEMO-Chemistry - 29-5-2016 at 17:42

Hi
I am pretty new to chemistry and so far have managed to get along with the help of google!

I havnt done very much so far and mainly this is due to a lack of equipment, I am very very slowly collecting glassware as I go.

My very noob question relates to a post I found on here regarding extracting the components of chili peppers. I didnt really find any answer to if its possible to extract the capsacin?? from the other components. The thread indicated it was difficult to obtain anything but the red oil like mixture.

My apologize I thought I had bookmarked the page!! it appears I didnt and I cant find it now.


I have several questions on the extraction based on various threads I have read on here and elsewhere.

Is it best to dry the peppers first?
Some reading has thrown up both arguments for and against this, so I am not sure if drying the chili first would destroy any of the compounds in the pepper?

What would the best way be to extract the stronger elements from the peppers?

I will leave the questions there for now but I have others, sorry I dont have the pages I have been reading. I updated firefox and seem to have lost my bookmarks!

I have basic distillation equipment but not many solvents, the ones I have are Ethanol, Methanol, IPA, Water, Chloroform that I recently made.

I was wondering if steam distillation would be the best way to go then follow this by solvent or AB extraction on the material left?

My main hobby has been RC Planes for a couple of years, and most of my chemistry interest revolves around that.

I have the read the forum alot before joining so i understand that people get suspicious with things like this, I dont want the extractions for pepper sprays or food use! Apart from learning how to do extractions this one is for an experiment to see what natural compounds (if any), can be used as environmentally safe alternatives to insecticides and to stop rodents etc chewing wood.

I have also read that some essential oils can be used as safe herbicides,although I believe the common one is oil of cloves.

Anything like this interest me, so i am looking at doing a number of extractions to test these things out. However I lack the knowledge of where to start, and to be honest some of what I read in the chili thread about the pure chili compound being dangerous scared me a bit.

I would rather ask and look stupid than read and do something stupid by mistake (doing something stupid on purpose is ok though :D ).

Sorry if this is spoon feeding but hopefully as I gain confidence i wont rely on asking so much.

Nick.

Edit

Sorry I did find one of the papers I read.
http://pubs.acs.org/doi/abs/10.1021/jf60214a035?journalCode=...

Is there anything I could use instead of Barium Chloride?

One other thing that interests me is the waxy Dihydrocapsaicin, would it be possible to extract and separate this? I was thinking seeing as it is 'wax' like, it could be incorporated into normal wax for application to wood. The downside being Rats are attracted to wax apparently so maybe this isnt a great idea.

[Edited on 30-5-2016 by NEMO-Chemistry]

[Edited on 30-5-2016 by NEMO-Chemistry]

Metacelsus - 29-5-2016 at 19:51

I don't think drying peppers would lower their capsaicin content. After all, many hot peppers are dried and used in food, and don't lose their spiciness.

For more information, see this thread: http://www.sciencemadness.org/talk/viewthread.php?tid=5329

Trevor9424 - 29-5-2016 at 20:01

These videos could help. Even if you can't directly do the exact methods proposed, you could try your own derivatives of them.

https://m.youtube.com/watch?v=cQIMLEwQWL0

https://m.youtube.com/watch?v=_4sR3Ph8MBk

NEMO-Chemistry - 29-5-2016 at 21:47

Thank you, thats helpful.

I was more concerned with oils in plants in general. Although I have read conflicting methods each saying the yield was higher with dried, then another saying a higher yield with fresh.

I think that was the page I had booked mark so thank you for posting it. I will watch the videos as well.

Nick.

[Edited on 30-5-2016 by NEMO-Chemistry]

NEMO-Chemistry - 29-5-2016 at 22:40

I found a reference here http://hortsci.ashspublications.org/content/39/1/132.full.pd... to ethyl acetate being used for extraction.

The following is taken from the paper and relates to separating the coloured compounds from the clear.

"In another method devised during the
present study and referred to as the “modified Bajaj method,” pepper powder described
above was extracted with ethyl acetate following procedures described by Bajaj (1980)
except that the filtrate was not allowed to evaporate, but instead mixed with 2.0 mL H2O followed by vigorous shaking. To each
mixture was added 4.0 mL of 0.5 NHCl and
2.0 mL absolute methanol before shaking.
The colored organic layer was removed by
syringe and discarded and the clear aqueous
layer retained and treated with 2.0 mL sodium
nitrite–sodium molybdate reagent."

I am sorry the formatting seems to come out incorrectly from the pdf when I C&P. What is the convention on this forum? Do i post the paper and the above in the other thread? Or is that considered 'Necro' posting?

Eddygp - 30-5-2016 at 04:03

It is fairly easy to extract capsaicin from chilli peppers.
However, unless you want to (or can) perform quite a few flash chroms or have HPLC equipment, you will only be able to isolate a mixture of capsaicinoids: capsaicin, dihydrocapsaiin, nordihydrocapsaicin and all those similar ones. They behave way too similarly to isolate without some further separation techniques.

Side note: last time I was isolating capsaicinoids for analysis of relative concentrations, I found that a very dark red oil that was insoluble in 1:1 EtOH:water was present during the solid phase extraction.

NEMO-Chemistry - 30-5-2016 at 06:27

Quote: Originally posted by Eddygp  
It is fairly easy to extract capsaicin from chilli peppers.
However, unless you want to (or can) perform quite a few flash chroms or have HPLC equipment, you will only be able to isolate a mixture of capsaicinoids: capsaicin, dihydrocapsaiin, nordihydrocapsaicin and all those similar ones. They behave way too similarly to isolate without some further separation techniques.

Side note: last time I was isolating capsaicinoids for analysis of relative concentrations, I found that a very dark red oil that was insoluble in 1:1 EtOH:water was present during the solid phase extraction.


In a couple of the papers I have it seems they have been able to discard the colored layers and separate out using solvents.

Near the bottom of the abstract it mentions discarding the colored material to prevent interference. I have some other papers floating on the hard drive that use different solvent combinations but apparently got good separation and were able to obtain pure product.

i will post them here when I find them again, I saved the bookmarks but lost them on a firefox upgrade!! I saved the PDF's but they are not where I thought they were.

sorry it was the same file as above! I had renamed it!

I have seen several that mention chloroform as one of the main solvents for good separation, no idea if they will help anyone but I can post here or the other thread if they are wanted?

[Edited on 30-5-2016 by NEMO-Chemistry]

Thank you for answering, if you dont mind me asking how many compounds did you manage to separate out with HPLC? (not an option but interested)

[Edited on 30-5-2016 by NEMO-Chemistry]

[Edited on 30-5-2016 by NEMO-Chemistry]

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NEMO-Chemistry - 30-5-2016 at 06:35

I also found a paper detailing the rectal temperature of mice fed with capsacin :o, I am going to skip that experiment though :)

Eddygp - 30-5-2016 at 14:50

I did not separate the substances, just calculated their concentrations from the peak area (which is proportional to concentration) of the graphs from the analysis coupled to the HPLC compared to an internal standard. However, I would have been able to extract nordihydrocapsaicin, capsaicin and dihydrocapsaicin. There was also a very small peak before capsaicin that didn't have perfect resolution so maybe a similar capsaicinoid would have eluted a bit mixed together. Since this was purely to calculate the conc. it was not a problem.

NEMO-Chemistry - 30-5-2016 at 17:21

Quote: Originally posted by Eddygp  
I did not separate the substances, just calculated their concentrations from the peak area (which is proportional to concentration) of the graphs from the analysis coupled to the HPLC compared to an internal standard. However, I would have been able to extract nordihydrocapsaicin, capsaicin and dihydrocapsaicin. There was also a very small peak before capsaicin that didn't have perfect resolution so maybe a similar capsaicinoid would have eluted a bit mixed together. Since this was purely to calculate the conc. it was not a problem.


Depending which paper you read capsacin can be a bit of a monster!

There is one that looks into the ability for it to cause DNA mutations. I am looking forward to giving this one a try

Karolin - 6-3-2018 at 16:38

2.0 mL sodium
nitrite–sodium molybdate reagent.

it doesn't mention what concentration he uses for this reagent, so what did you used, i'm trying to extract capsaicin as well, but i got stucked when i try to separate it from the colored material

ninhydric1 - 6-3-2018 at 18:01

This thread should be merged with this capsaicin thread:
http://www.sciencemadness.org/talk/viewthread.php?tid=5329&a...

The thread does mention a glycerol-ether separation method, which seems to be effective. Not sure about what the sodium nitrite-molybdate reagent does, but the glycerol-ether method seems more OTC.

EDIT: Oh look, NEMO's first post!

[Edited on 3-7-2018 by ninhydric1]