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Bander
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Piperine-Mediated Bioavailability
I propose that we start a general Piperine and Piperine-mediated-bioavailability information-dump-thread. Here's a bit of what I've found so far and why it's
interesting.
It is well known that Piperine can enhance the bioavailability of many phytocompounds (and more) by inhibiting various P450 cytochromes (CYP1A1, CYP1B1, CYP1B2, CYP2E1, CYP3A4) and by other methods. Since Piperine extraction is so humorously easy and already well covered (anhydrous alcohol extractions combined with dry/neat
pepper microwave cell rupture(1)) I figure this topic should be fairly interesting, though obtaining quantitative data would\will be complex.
Has anyone else played around with Piperine to increase the bioavailability of various chemicals? I am planning to start a daily regiment of Curcumin with Piperine in the coming months in order to test out any qualitative effects before I really need it's anti-inflammatory effects
(say, in case of further H5N1 influenza mammal adaptation and the related cytokine storms). It would appear that this combination would also act as an analgesic as
Curcumin acts as a COX-2 inhibitor (though I don't think it's very selective for COX-2, so it's more like ibuprofen than Vioxx) and
Piperine stimulates the release of beta-endorphins(2). Also interesting is that Piperine was as effective as nalorphine in reversing morphine-induced
respiratory depression(3).
The Bioperine guys who hold patents, # 5536506 1996 and # 5744161 1998, had an excellent site up (on above topics, even extraction) for a while that
the lot of you probably already know about. The internet archive has an imageless backup but if any of you have a full backup I'd be mighty appreciative.
I currently extract with a ghetto-like setup using denatured alcohol on ground pepper that has been microwaved dry (with a glass of water) for about a
minute in a 650w consumer oven. I have definitely noticed improved (qualitative, but visually obvious) yields with less dark decoloration with
pre-microwaving as opposed to simple waterbath heating with solvent. I usually test for Piperine with sulphuric acid, a distinctly red color results.
I haven't tried it yet, but an appropriately dilute suspension of pepper in a non-polar solvent all in the microwave together is supposed to work
even better. I've tried with polar solvents (yes, hilarious) to obvious bad effect. I assume the brow-greyish 'goo' left with the
yellow Piperine crystals in an alcohol extraction is Chavicine (it smells like it). While it is not vitally important, does anyone have any
suggestions for seperating Chavicine from Piperine? A water wash should work (Piperine being 40mg/L in water with Chavicine being
fairly soluble) but it hasn't for me.
Or general information? The below linked paper seems promising if you can get access.
Synergy and other interactions in phytomedicines
Author: Williamson E.M.1
Source: Phytomedicine, Volume 8, Number 5, 1 October 2001, pp. 401-409(9)
Publisher: Urban & Fischer
Abstract:
Synergistic interactions are of vital importance in phytomedicines, to explain difficulties in always isolating a single active ingredient, and
explain the efficacy of apparently low doses of active constituents in a herbal product. This concept, that a whole or partially purified extract of a
plant offers advantages over a single isolated ingredient, also underpins the philosophy of herbal medicine. Evidence to support the occurrence of
synergy in within phytomedicines is now accumulating and is reviewed here. Synergistic interactions are documented for constituents within a total
extract of a single herb, as well as between different herbs in a formulation. Positive and negative aspects of interactions are discussed together
with the methods used to identify and measure synergy. The evidence is divided into experimental, in vitro instances, as well as clinical examples
where available. Herbs discussed include Ginkgo biloba, Piper methysticum (Kava-Kava), Glycyrrhiza glabra, Hypericum perforatum, Valeriana
officinalis, Cannabis sativa, Salix alba and others.
http://dx.doi.org/10.1078/0944-7113-00060
(1) http://rapidshare.de/files/6610631/Microwave_assisted_extrac...
(2)Eun, J.S. (1986). A study on the mechanism of analgesic action of piperine. Yakhak Hoeji 30(4); 169-173.
(3) Singh, N. et al. (1973). A comparative evaluation of piperine and nalorphine against morphine induced respiratory depression and analgesia.
J.Res.Ind.Med. 8(4); 21-26.
[Edited on 26-10-2005 by Bander]
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Tacho
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I have extracted piperine a few years ago. I can't remember the details, but I remember a few things:
- The yield varies wildly in quantity and quality depending on the source of your pepper.
- It was a tedious process full of filter papers clogged by resins. Resins are your # 1 enemy.
- The final step was to add water (hot?) to the ethanolic extract and wait a couple of days for precipitation. Luck was needed, or a nice useless
yellow emulsion was formed. I remember adding some base (KHO) somewhere in the process.
- During one of my extraction experiments I obtained a solution that had this wonderfull lemmon-flower-fruity smell. I just couldn't get enough
of smelling it. I bet it was mutagenic.
- After obtaining the precipitated crude piperine as yellow-brown chunks, you must get rid of the resins.
I have bored you enough with my memories, here goes the recipe: Cover the dry piperine chunks with pure acetone and grind them with a glass rod.
Piperine goes to the bottom as a light yellow powder and garbage stays in the solution.
Repeat a couple of times. You loose some piperine, but the final product is quite pure.
Don´t even think of recrystalization. I tryied all possible solvents, none works.
Try it and post your results.
[edit: joke deleted]
[Edited on 27-10-2005 by Tacho]
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The_Davster
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From a university o-chem lab manual, a procedure for extraction of piperine is aproximatly as follows(from memory)
1) Reflux ground pepper with alcoholic potash
2) Distill of EtOH
3) recrystalize from acetone/hexane
probally should have been a wash with water step between 2) and 3) to remove potash.
Well I gave it a halfhearted attempt today.
K2CO3 was added to 96% EtOH and water was added to this so that all carbonate dissolved in a single layer(a bit of water produced 2 layers). A pile
of freshly ground pepper was added and refluxed for ~20min. This was then filtered, then the filtrate distilled. Result was a dark brown solution
with a horrible pepper-related smell with a brown ppt in the bottom.
I also got a drop or so of the brown solution on my finger while washing the glass afterwards, now my finger is all tingly at the point of contact.
Well since it is a pepper extract it cannot be harmfull...right? The MSDS for pipererine seemed pretty tame.
I might work up the aforementioned solution at a later date to ger pure(ish) piperine.
BTW what is piperine usefull for?
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Tacho
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I have found some crude piperine left in my attic, so I decided to make some pictures of the cleaning process with acetone.
Maybe the purified piperine can be recrystalized. Never tried that.
The only commercial use I know for piperine is the one mentioned by the original poster. One could use to give food a pepper "sting", but
why not use pepper itself?
Some people use it to make piperonal. You can find extensive discussion on the subject in the net.
I find piperine interesting because it's extraction is chalenging and the final product is a crystaline chemical, quite complex and absolutely
harmless (you EAT pepper don't you?). I thought of finding some use for it as an organic insecticide or reppelent along with catnip's
nepetalactone.
Unfortunatelly my catnip sedlings died in the tropic's heat and the piperine was forgoten until now.
Don't forget to scratch your eyes while purifying piperine. It's unforgetable. Pure pleasure.
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Tacho
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By the way, there is still a lot of piperine in the brown acetone extracts. Let the acetone evaporate and crude piperine will crystalise.
Interesting, the brown resin left (free of acetone of course) has a much "hotter" taste than the purified piperine.
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S.C. Wack
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Drug-store IPA is a fair recrystallization solvent. I suggest recrystallizing a few times, a product that is almost white while still wet with IPA can
be obtained.
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epck
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Hmm...I actually found acetone to be better for recrystalization. It took several days in the freezer for the xtals to completely form and the
product wasn't as pure when using IPA.
A dark 'oil' formed as well as the xtals which was difficult for me, without a aspirator (I know, I know), to completely seperate from the
product. This meant several rextalizations were necessary which were time consuming. The acetone seemed much quicker and easier.
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S.C. Wack
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I assure everyone that piperine is much less soluble in cold, non-anhydrous IPA than in boiling (in which it is fairly soluble), and that
crystallization starts immediately and is soon over if cooled.
I note that acetone:hexane 3:2 is mentioned in the 3base files a couple times.
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epck
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Non-anhydrous IPA may be the difference. I was using anhydrous IPA for the rextalization. Looks like I have something to do tonight.
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Polverone
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Bump!
Tacho, are you sure you can't recall details of your pepper extraction? It looks like you had a fair amount of crude piperine left in your attic. I
have tried the microwave-assisted extraction of crushed pepper with petroleum ether, imitating the attached article from the Rhodium archives. It
seemed to work fast enough, and certainly to give cleaner (lighter-colored, anyway) crude material than the couple of alcoholic extractions I had
tried before, but I worked on a very small scale and have not repeated it because of fear of disaster in my unmodified domestic microwave.
Later, I tried extraction on a slightly larger scale again using petroleum ether but no microwaves. It took longer. Petroleum ether seems to have
limited solvent power for the pepper extraction. When I would turn the hot plate off for the night I saw a bit of light-yellow flaky material
accumulating on the side of the flask after the solvent cooled. Eventually I filtered the solvent into a jar while hot. Especially after I evaporated
about half the volume, it would go cloudy when cold, but no solids appeared. Eventually I evaporated it down to a thick oil. I tried dissolving in
boiling 70% IPA but nothing recognizably crystaline appeared on cooling.
Though purification is obviously a necessity at some point, I am more interested in how to process larger quantities of pepper to get crude material.
I can buy pepper pretty cheaply in bulk, but I can't afford to go through liters of solvents. Is a soxhlet the only practical non-microwave extraction
method?
[Edited on 2-2-2006 by Polverone]
Attachment: microwave-pepper-extract.pdf (182kB)
This file has been downloaded 1698 times
PGP Key and corresponding e-mail address
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Tacho
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Polverone,
I did make a write up at the time, but I could not find it. I'm afraid it's lost.
I'm travelling now, so I won't be able to do further search.
Here is what I remember, hope it helps:
1- I used 2 liter PET soda bottles with large ammounts of ground pepper. 500 grams or so. Enough to fill about 1/2 of a PET bottle. Filled that with
ethanol (from gas stations, it's a fuel in Brazil). Remember that the pepper swells, even with alcohol.
2- Left there for about a day, with an ocasional shake. Let it settle, removed the clear brown liquid from the top, about 500 ml, concentrated that
liquid to, say, 100 ml by distillation and returned the 400 ml of distilled ethanol to the PET bottle.
3- Repeated that last step a few times, so that the 100ml of ethanol holds crescent ammounts of piperine. Its a straightfoward concentration of
extracts, recycling the solvent. Ethanol is an excellent solvent for piperine, so I estimate that the economical number of extraction cycles would be
about 4. Depends on how much you paid for the pepper. Mine was cheap, so was the ethanol, so I did't go crazy trying to extract the last drop from
the pepper. At the last cycle, after removing the clear brown liquid I just discarted the whole bottle with the pepper/ethanol paste.
That piperine in the picture I posted is probably the sum of that obtained doing this process in a few bottles at the same time.
At the time I did that extraction, I followed a procedure I found on the internet that requires mixing with ethanolic KOH, filtration, adding to hot
water etc. Today I would skip all that. I would just leave the concentrated ethanolic extracts on a warm plate until all ethanol evaporates. I am
almost certain that the horrid resinous goo left would eventually (a couple of weeks?) crystalise in chunks that could be purified by the acetone
process.
I noticed that the price of bulk ground pepper jumps up and down a lot. It is quite cheap some periods of the year. Also, remember that old ground
pepper (with less aroma) is cheaper but provides the same ammount of piperine.
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S.C. Wack
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I find it difficult to believe that I am the only one to find IPA satisfactory. Though I never used 70%. 87(with salt)-91(without)% was used. A
boiling saturated solution of yellow piperine (I am talking of at least ounce amounts) precipitates a very finely crystalline off-white product which
I prefer. A less than saturated solution gives larger, slightly darker crystals, not powdery at all. Heating below boiling under not-saturated
conditions was with glass/watch glass/hot plate, and two sharply-defined layers were observed on many occasions after all the piperine had dissolved,
typically 15-30 minutes. Stirring mixed them and they did not reform. Captain Obvious says that if one cools a boiling solution of piperine and gets
nothing, they are using way too much solvent. It does take at least 3 recrystallizations from the initial product to get it almost white with this
solvent, but that is how chemistry goes. There are no losses as everything is worked up, since one has to do this anyways when using denatured for
extraction due to the impurity problems.
The main problem with using the usual US denatured alcohol on a large scale regardless of apparatus is the load of dark piperine-absorbing crap that
is extracted with the piperine. But even with just denatured and IPA, it was not a big deal, just the working up of a few liquors and crystals in
various stages of purity. This is the "dark oil" mentioned earlier and one can crystallize out much of the piperine before any of this oil forms, at
least with the usual denatured. It is desirable to pour off the solvent occasionally during crystallization to keep the crystals from being crapped
on, because the crap suddenly precipitates at a point. The solvent is brown and smells bad at this point. But the piperine always comes out first
(contaminated with some crap) so no big deal. Then fresh (or rather the liquors left over from recrystallization of the crystals that already
separated) IPA was added, crystals revealed in the crap and separated, and the liquor then evaporated some to repeat the process. Even room temp IPA
is OK for washing off crystals but there is no reason not to keep it in the fridge.
The problem with say, putting a pound of pepper in each of several 1 gal. distilled water bottles, covering with denatured, shaking every so often,
decanting, and repeating, is the repeating. Not because of solvent because one can just distill, but because it takes a long time. The pepper forms a
dense, not-very-porous layer. And heating it just makes a more impenetrable layer. An improvement is the use of paint buckets with a small hole in the
cover for a paint stirrer, such as are found in hardware stores and fit into hand drills (rigging the drill=less fun). Obviously if one has a huge
>1 neck flask + overhead stirrer + condenser + heat...
It was also found important (for yields) to get a finely ground pepper, or grind the coarse pepper to that point. I didn't worry about filtering
because as usual, decantation is the way to go. I also saw the addition of water to precipitate piperine recommended in the literature but a small
scale test was unsatisfactory and was never tried again.
Unless one has super pepper, Soxhlets (even two at a time) are not enough if one wants to do large scale, as I never got more than 5% with my
(non-gourmet) pepper, and 3% was the low end. Well, I do remember seeing this incredible Soxhlet for auction a year ago. Whoever got that could, if
they have a flask that fits it. But maybe something like this would be best:
Attachment: iec_16_1125_1924.pdf (134kB)
This file has been downloaded 1542 times
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Polverone
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Thank you for the advice. I have thus far been working on such a small scale that it is possible I've overlooked the piperine among the oily mess. I
may have to scale up to see anything useful from this.
PGP Key and corresponding e-mail address
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Tacho
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| Quote: | Originally posted by Tacho
. I am almost certain that the horrid resinous goo left would eventually (a couple of weeks?) crystalise in chunks that could be purified by the
acetone process.
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I was wrong.
I extracted 1kg of ground pepper with ethanol and let the final concentrate evaporate on a warm plate.
The result was a two phase one: a black resinous oil and a solid, elastic (!) deposit.
The black oil eventually showed some crystallization but very little piperine could be seen on an acetone bath.
I'll try some IPA/water recrystallization inspired by S.C.Wack.
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BetaBee
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| Quote: | Originally posted by Tacho
| Quote: | Originally posted by Tacho
I'll try some IPA/water recrystallization inspired by S.C.Wack. |
NOOOooooo. You have to try ethyl acetate, it's the only real solvent for resolving piperine. And you must use a seed and cool it down over hours in
order to properly x-talize it.
And for the record, i have yet to see an actual pure piperine crystal on the net. Maybe someone could point me somewhere, but piperine is a colorless
substance. The other isomers, [Z,E], [E,Z] or whatever are the colored impurities, eg chavicine.
You can get piperine to crystallize in the resin, but it is still worth it to do the ethanolic KOH step to increase yields.
I was involved in a competition with 30 other people to get the purest piperine, which should have prismatic and colorless crystals. When you have
yellow needles, that means there are impurities. Don't want to sound aggressive, but i just wanted give my two cents so that y'all can reduce you
burning eyes, nose, skin, wounds, and yes it happened to me once, ya...... i scratched the boys and it was sooo much worse than ben gay(don't ask).
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Tacho
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Thank you BetaBee.
You mean using ethyl acetate to recrystalize the crude piperine or to extract it from the resinous goo?
I extracted the pepper to the resinous goo without the KOH/filtering step on purpose. Exactly to try to find an easier route to the product.
I dissolved the resinous goo in 100ml of IPA, brought it to boiling, added just enough hot water to show the firsts signs of emultion (white haze) and
let it cool slowly. I expected piperine to crystalize. Instead, I ended up with another two phase solution, darker bottom and lighter upper phase.
Some white/yellowish in between.
Do you suggest I distill off the water/IPA and try ethyl acetate?
An easy route from goo to crystals would make extraction of piperine quite simpler.
And look at the bright side: you could have been gay WITH piperine. Ouch.
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S.C. Wack
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Of course I mentioned the layers before. Nowhere do I find piperine mentioned as being colorless, but in quite many color is mentioned. Someone in the
older journal literature said that the yellow color was due to contact with oxygen. As I said before, the larger crystals are darker than the powder,
which is somewhere between tan and yellow, and quite light. The finest powder is nearly white, and I would expect that the piperine precipitated by
water would be the whitest, being the finest by far. Merck and Lange's give a mp of 130. I held the temp of my product at 128C for 10 minutes, given
the quotes in the 3base collection, but it did not even soften. It melted sharply at 130C. Large amounts have a faint and quite pleasant smell.
20 grams of my product were heated with 85 ml 91% IPA until it dissolved. It was cooled to -4C and vacuum filtered after an hour, followed by heating
in air, giving 18 grams of dry fine crystals.
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Sergei_Eisenstein
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Piperine is rather soluble in ethyl acetate but poorly soluble in petroleum ether. Combining the two solvents may give a satisfactory
recrystallization solvent mixture.
Crystals may take their time to form. To speed up the process, you may dissolve the piperine in a minimal amount of ethyl acetate (warm) and add it to
a comparatively large amount of petroleum ether (e.g. 5 ml EtOAc and 40 ml PE). While the PE is stirred with a stirbar, add your piperine solution
dropwise to the PE. White clouds of product will form. When the milky clouds start to materialize as crystals, addition of your piperine solution can
proceed faster. Put on an icebath or in the fridge. The pure compound is a pale yellow solid (from EtOAc/PE).
Compared to using a combination of an alcohol with water, the EtOAc-PE system gives a product that is easier to dry. In my hands, aqueous MeOH gave a
voluminous precipitate that had a pasty appearance when vacuum filtered.
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eesakiwi
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SwIms been doing the pepper thing for a while, on different boards (WD's).
And had pretty much the same experience as above.
SwIm used Meths (Ethanol denaturated with Methonal/Pyridine) IPA, DCM, Tolulene.
Meths was best as the general solvent.
DCM, talk about co$t! not $ viable.
Tolulene took out a lot more colour, but the smell of Turps got to swIm, don't put it in the fridge, the smell gets into everything, comes out in
yah burps & its hard to get rid of, swIm'l stay away from Tolulene from now on unless its nessarary.
IPA was a little cleaner than meths, & cost more.
Theres about 25%+ pepper volume loss of the solvents.
The pics above were virtually exactly the same as swIm experiences.
After a lot of trys swIms just gone with this method.
2L sodapop bottle, add 1Kg Pepper, microwave till warmish,
add Meths (1Litre), shake, Microwave till quite warm & shake,
let pepper settle & pour off Meths into jar & freeze, crystals seperate out.
Put crystals aside, this is the nice clean first extraction.
Add more Meths to 2 litre, microwave etc (do this twice again)
Filter the meths/pepper solution.
Boil off meths till its a brown goo. = Pepper extract.
To clean up, add the same volume of Meths/10% KOH solution as there is extract, put this in a jar & slowly add boiling Water till the solution
starts to go yellowish (sorta suddenly) cool then freeze & pour off water.
Once yah have the dirty Pepper extract, Dissolve it in hot Acetone,
then add Petroleum Ether (Hexane etc) slowly untill Pet E starts to go clearish, then cool.
The yellow bottom layer will crystalize out (looks just like the first clean extract) while the solvent stays brown.
Boil down the solvent again, so its less vol than where it was when yah added Pet E,
add Pet E again so crystals drop out again. if yah want too.
---------
A few notes,
They say use a Meths/10%KOH solution to extract out the stuff from the Pepper, KOH adds a lot to the Co$t of the experiment, so swIm just uses
Meths.
SwIm does think that it is benificial to use a 10%KOH/Meths solution when doing the Meths/Water seperation. The sediment is a lot more yellower&
it drops out cleaner/sharper too.
SwIm has tryed the Potassium Permanganate KmNO4 addition to the extract to get Piperidine, drop by drop by hand - boring, & got nothing really.
The smell did change to a Marshmellowish smell, actually to pin it down, it smelt like the first split second of the marshmellow smell, just that
initial bit, marshmellow does change after that first second.
But there was no real product in the finish.
ona side note, theres mention of that smell when doing the Ephedrine/KmNO4- Cathione preperation, same smell. also a mention of a
Benzaldehyde/Almond smell.
SwIm tryed the Copper Sulphate/DCM/Pepper extract - Piperidine experiment.
The result was pretty much what went in (suprised swIm, 'e didn't expect to get anything!) same volume as started with too.
Except it didn't smell like the extract, nowhere near as strong, it was a light brown rectangular crystal after cleaning (same shape, larger,
brownish- not yellow) melted at 80 deg C.
SwIms gonna try the CuSO4/Copper Sulphate again, but with some Tartaric acid as well, its mentioned later in swIms source, which swIm will place here
later when 'e gets it.
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IPN
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Few weeks ago I extracted 1kg of black pepper with 1l of ethanol (95%, denaturated with bitrex) in a soxhlet extractor for approximately 50h. Today I
had the time so I distilled off most of the ethanol and a pleasant smelling oily liquid remained. I added 250ml of 2°C DH2O while shaking the flask
and a light brown precipitate formed that dissolved immediately as I continued to shake the flask. A slightly dark orange liquid was obtained which
had heated up a bit so I put it in a bucket with cold water and continued with some other stuff. After half an hour or so I checked on it and found
out that there was a considerable amount of black oil on the bottom and that the liquid had changed to a lighter color. I had expected that some kind
of yellowish mass would have precipitated like the last time I tried extracting pepper but instead I got this oil.. Is there any way to get
crystalline piperine out of this stuff?
Here's a pic on what it looks like:
http://koti.mbnet.fi/otto2000/pepper_extract_with_water.jpg
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S.C. Wack
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It might have been better to have added hydroxide before adding water. Some stuff precipitates right off, some more upon addition of water, some crap
remains in the base-water. Perhaps you could try distilling off the dark oil with steam until nothing more comes over? You may find that the oil
crystallizes some to a very dirty mass of mostly piperine. It happens sometimes, not right away. The dark oil is more soluble in IPA and perhaps aq.
acetone than piperine, which will crystallize out first if left to evaporate.
Maybe you'd like to give this a try -
Preparation of Piperine
One ounce (28 grams) of standard black pepper was placed in a 500 ml flat bottom
flask along with 250ml Everclear to which a condenser was attached to prepare
for standard reflux. With vigorous magnetic stirring, the mixture was refluxed
at just above boiling temperature for 3 hours, allowed to cool, and the mixture
was suction filtered to retrieve the filtrate. Standard distillation
concentrated the filtrate to approximately 20 ml. The concentrated extract was
then added to 20 ml of 10% KOH in Everclear which was heated on a low setting on
a hot plate. To this mixture, water was added dropwise to form a yellow
precipitate until no more precipitate formed. This was suction filtered and
recrystallized with 30 ml of hardware-store acetone made anhydrous by drying
with epsom salts. Yield was approximately 1.3g of crude piperine, which was
stored in a dark place overnight. (approximate because the scale in question was
at best accurate to tenths of grams.) You can do this a couple of times in a
night without much effort, which can effectively yield 2.5 grams.
http://www.intellicandy.com/oldschool/chemcandy/piperine.txt
[Edited on 15-7-2006 by S.C. Wack]
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IPN
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Ok, I'll do the final steps a bit different the next time I try the extraction..
I decided to try the steam distillation and added ~1l of DH2O to the flask and heated to boiling (my steam generator is still under construction..).
After few minutes some clear oil started to come over.
http://koti.mbnet.fi/otto2000/steam_distilling_pepper_extrac...
http://koti.mbnet.fi/otto2000/oil_collecting_in_receiver.jpg
I'll continue the distillation until no more oil comes over. Hopefully I can then get the piperine isolated.
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xwonchem
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Anybody thinks that: using piperine to produce heliotropin by one step slight oxidation. I am trying to do this but I want someone help me finding the
way and materials relate this problem. Piperonal in my country has large potential and much application. I has no enough money for buying good reagent
so that I need saving money.
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xwonchem
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does other way extract piperine that doesn't use organic solvents?
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xwonchem
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Nobody here
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