Sciencemadness Discussion Board

Indole from feces

Pyridinium - 19-5-2005 at 08:12

...now THAT has to be one of the nastiest extractions you could ever hope to do. :o Was reading about it in the Merck Index.

Indole is such a fascinating compound. I want to own it, just for the sake of having it.

I've already seen the "best/worst smelling compounds" thread, and speaking of feces and fecal odors, I'd have to mention n-butanol. Some people don't get bothered by it though.

Anyone ever worked in the perfume industry and added small amounts of indole to the mix? Just curious.

I had to edit this: for those who don't know, indole is used in SMALL amounts to impart an actual pleasant odor to perfumes sometimes. Just so you don't think I was talking about dirty tricks.

I know, I know, I shoulda put this post in the Biochem section. Seeing as I'm a biochemist myself.

Bah. Typical n00b / Kewl error.

[Edited on 19-5-2005 by Pyridinium]

[Edited on 19-5-2005 by Pyridinium]

sparkgap - 19-5-2005 at 08:38

"...has to be one of the nastiest extractions you could ever hope to do..."

You think? Ask chemoleo about his procedure for extracting urea from urine. :D I think that thread is somewhere in the forum...

Anyway, I don't know if you'll be able to get sizeable amounts of indole and/or its congener skatole from manure. IIRC, they occur in miniscule amounts. An acid extraction might work, but I'm not sure since I cannot recall indole's pKa... :( Organic solvents won't be able to isolate since they'd leach stuff like coprosterol along...

On another note, indole can be used to make the stuff that colors your jeans. ;)

sparky (~_~)

Pyridinium - 19-5-2005 at 09:31

Quote:
Originally posted by sparkgap
You think? Ask chemoleo about his procedure for extracting urea from urine. :D e. IIRC, they occur in miniscule amounts. An acid extraction might work, but I'm not sure since I cannot recall indole's pKa... :(


I can tell you a few stories about experiments with urine for the phosphates / urea / uric acid and breakdown products. (ahhh... the Hennig Brand school of chemistry...)

At one point during heating urine in carbonaceous sand, you can get a smell that is distinctly similar to barbecued meat. That is, if you can get past the rest of the capital-lettered STENCH. Do not at any moment visualize yourself vomiting during the procedure, or you will. (side note: I know all about the phosphine at high temps. Don't think for a minute I'm heating that mixture to redness without a gas mask)

Indole's pKa is around 16.8 I think.

I was thinking some type of elution / column chromatography would be best, though an acid/base/solvent extraction would be a good start to get it away from its brown "friends" and high-molecular weight hangers-on.

Everyone seems to want these silly indole alkaloids. ;) I just want indole. Pure indole. Just to have it.

[Edited on 19-5-2005 by Pyridinium]

Nicodem - 19-5-2005 at 10:50

Quote:
I just want indole. Pure indole. Just to have it.


If that's all you want, then perhaps you should consider a less shity method. Maybe a synthesis?

You can make indole by decarboxylating indole-2-carboxylic acid which is prepared from phenylhydrazine and pyruvic acid by the Fisher indole synthesis reaction. Pyruvic acid can be made by pyrolysis of tartaric acid in the presence of H2SO4. Phenylhydrazine can be made in one pot from aniline. Aniline from, well...
...it's still much better than working up shit to obtain a few mg of skatole or indole.

Besides, you can't use an acid/base extraction on indole as it can't be protonated in water. It is a few thousand times less basic than water (and also about a hundreed times less acidic than water).

Pun intended...

Pyridinium - 19-5-2005 at 11:17

Quote:
Originally posted by Nicodem
Quote:
I just want indole. Pure indole. Just to have it.


If that's all you want, then perhaps you should consider a less shity method. Maybe a synthesis?

You can make indole by decarboxylating indole-2-carboxylic acid which is prepared from phenylhydrazine and pyruvic acid by the Fisher indole synthesis reaction. Pyruvic acid can be made by pyrolysis of tartaric acid in the presence of H2SO4. Phenylhydrazine can be made in one pot from aniline. Aniline from, well...
...it's still much better than working up shit to obtain a few mg of skatole or indole.


While I don't consider urine experiments to be beyond the pale of acceptable biochemistry, I definitely have no intention of working with feces to get a compound... (though dried cow manure isn't so bad, I'm sure it lacks much indole)

...the aniline route sounds good, might have to do some digging in the literature and perhaps give it a run.

Another way might be to degrade tryptophan enzymatically (or chemically). Probably yields more indole than would feces.

I just thought indole from 'biosolids' would go along nicely with Chemoleo's urea method...

Organikum - 19-5-2005 at 11:30

Actually why not? Methinks that the smell is favorable over the unhealthy properties of many organic compounds...

The MERCK says it´s volatile with steam...
So you have to steamdistill the shit (sic!). or extract and steamdistill afterwards...

Post pictures! ;)

/ORG

PS: Find out what one has to eat to rise the amount of indole in the starting matter! Maybe the digestion product of certain animals is better?

In the end it´s all just fertilizer....


Addon: A quick Google search reveals that digestion of Protein forms the indole, so carnivore feces might be preferable (hey! Dog-shit! Thats a cheap prescursor!).
Or do it biosynthetikally with some feces for inoculation and a trypotophan salt broth...
here
andhere

"indole in feces" gives 113 hits in pub-med alone. Can´t be so disgusting... :D

[Edited on 19-5-2005 by Organikum]

evil_lurker - 19-5-2005 at 11:50

Sounds like a really shitty way to get indole... (sorry couldn't resist!):P

Pigshit!

Organikum - 19-5-2005 at 11:53

Quote:

3-Methylindole (skatole) and indole production by mixed populations of pig fecal bacteria.

M T Jensen, R P Cox, and B B Jensen Department of Animal Physiology and Biochemistry, Danish Institute of Animal Science, Tjele.

Abstract
Pig fecal slurries converted added L-tryptophan either to indole without detectable intermediates or to 3-methylindole (skatole) via indole-3-acetate. The initial rate of production of 3-methylindole was greatest at pH 6.5 and less at pH 5.0 and 8.0; the initial rates of indole production were similar at pH 6.5 and 8.0. More than 80% of the tryptophan added was converted to 3-methylindole at pH 5.0; at pH 8.0 85% was converted to indole. Both pathways had similar Km values for tryptophan and similar maximum rates. Indole-3-carbinol and indole-3-acetonitrile completely inhibited the production of 3-methylindole from indole-3-acetate but had no effect on the reactions involving L-tryptophan.


Emphasis by me.

Hey Nicodem, with all respect, but isn´t that a more conveniant way to indole in excellent yields from simple precursors?
l-tryptophan is completely OTC here where I live and pig-feces..... :D

Can somebody with pub-med access obtain the complete article and post it?

thanks
/ORG



[Edited on 19-5-2005 by Organikum]

S.C. Wack - 19-5-2005 at 13:29

the article.

Attachment: appl_env_microbiol_3180_1995.pdf (276kB)
This file has been downloaded 1280 times


Pyridinium - 19-5-2005 at 13:40

Organikum, you might be right. There are some organic compounds that I'd even less rather work with...

Looks like I opened up a nice can of worms, er., uh, Scheiss.

I might even have something around here that details the enzymatic breakdown of the tryptophan into indole. I was just too lazy to look it up :-P

You could have a beaker 1/2 full of pig feces, or better yet culture the bacteria from pig feces and take THOSE and put them in the beaker. Keep it at body temp., buffered at pH 8.0 with, say, pyrophosphate or Tris, something that won't inhibit tryptophanase.

Slowly feed the tryptophan into it and there you go. The enzymes do all the work. And who thought feces weren't valuable?

Then when you're done you could steam distill the mess and collect the indole.

Looks like we can come up with a procedure, with maybe a few "bugs" to work out. I might have to try it sometime and do a write-up...

Pyridinium - 19-5-2005 at 14:01

I've an ACS Monograph from 1929, the Biochemistry of the Amino Acids. They do briefly mention the breakdown of tryptophan by intestinal bacteria.

Apparently, indole and its derivatives (especially indican) can also find their way into urine, depending on how much protein (meat) you eat.

One interesting fact I picked up is you can use a pine stick, moistened with HCl and then dried (!) to determine the presence of tryptophan. It will turn purple, according to this book.

But the choicest bit of ALL was this:

"...Donaldson has shown that the symptoms of autointoxication induced by voluntarily holding of feces for 100 hours were almost immediately relieved by passage of feces in response to an enema."