Sciencemadness Discussion Board

Decomposition of hairs to yield amino acids

math - 7-11-2008 at 10:38

hello,

I've read keratin, the main costituent of hairs,
is made up mainly of cysteine and short amino
acids;
would it be possible to break keratin to
yield free amino acids?


Thank you in advance

Maja - 7-11-2008 at 10:57

A little bit information here : https://sciencemadness.org/talk/viewthread.php?tid=5399

math - 7-11-2008 at 12:19

thank you I looked at it but couldn't find any help

[Edited on 7-11-2008 by math]

Trifluoroacetic - 7-11-2008 at 15:14

You can hydrolyze hair proteins with hydrochloric acid. sodium hydroxide should work to. I believe that is why it is added to draino.

chemkid - 7-11-2008 at 19:46

Careful! i have been down the road of hydrolyzing hair. Not sure if HCl will work, but NaOH certainly will in a hot solution. However hair is rich in disulfide bridges which dissolve in a basic solution. when the solution turns acidic:

(S2)2- + 4H+ --> 2H2S

Learned this the hard way. If it does dissolve in HCl you will certainly experience some hydrogen sulfide. None from dissolving in NaOH as long as you keep up the pH.

chemkid

PS sorry for the horrible spelling the computer whcih i am on has no spell check

[Edited on 7-11-2008 by chemkid]

Sauron - 8-11-2008 at 04:57

See the proceduresin Org.Syn. by exactly this strategy although the choice of reagent is important if you expect to isolate particular AAs.

You need rather a lot of human hair freed from other content. A barber shop would be a good source, a beauty salon perhaps better.

I'' attach the monograph.

[Edited on 8-11-2008 by Sauron]

Attachment: CV1P0194.pdf (129kB)
This file has been downloaded 1367 times


math - 8-11-2008 at 05:41

As my idea is to get a mixture of free amino acids,
I'd say I should use the hot NaOH solution proposed by chemkid,
because if HCl takes away sulphur atoms in form of hydrogen sulfide,
sulfur-based amino acids would obviously be decomposed in something else.

The problem is which container to use, as along with free amino acids I'd get
some sodium silicate if I use a glass flask.

Should one expect good yields if not separing AAs and getting just mixture?

Thank you Sauron

Sauron - 8-11-2008 at 05:52

Using the Org.Syn. method you get 100 g cystine (not cysteine) from 2 Kg human hair. That is not bad.

What is the point of getting mixed AAs? Planning on putting it under pressure with NH3 and CH4 and running lightning bolts through it while standing by wild eyed shoutine "Life! Give my mixture LIFE!" ?

Believe me, pure AAs both chemically and enantiomerically are a lot more fun than a puddle of vital chemicals. It really isn't going to wake up, look at you and cry "Momma"

chemoleo - 8-11-2008 at 06:20

Check this

https://sciencemadness.org/talk/viewthread.php?tid=2210&...

Sauron - 8-11-2008 at 06:50

Yes of course a wide variety of human and animal proteins can be harvested for AAs, histidine from red corpuscles, arginine from hooves and horns, if memory serves. See Ullmann's for a general recitation of amino acid production. (Arginine is ultimately the source of hydrazine prepared clasically from gelatine.)

Sometimes these methods are expensive, Histidine for example is made IIRC, using HgCl2, which apart from toxicity issues is bloody expensive.

Cystine is one of the least costly one to prepare from natural sources.

I do believe there is an entire book on this subject in the forum library. I would advise the thread author to avail himself of it.

math - 8-11-2008 at 08:05

Quote:
Originally posted by Sauron
Using the Org.Syn. method you get 100 g cystine (not cysteine) from 2 Kg human hair. That is not bad.

What is the point of getting mixed AAs? Planning on putting it under pressure with NH3 and CH4 and running lightning bolts through it while standing by wild eyed shoutine "Life! Give my mixture LIFE!" ?

Believe me, pure AAs both chemically and enantiomerically are a lot more fun than a puddle of vital chemicals. It really isn't going to wake up, look at you and cry "Momma"


lol, I found that reply of your really entertaining. :D

my idea is a lot simpler and practical, getting mixed AAs neutralized enough to be eatable and give you protein supplement in diet.


[begin of funny reply]
you know, in scotland nothing is wasted, let alone something useful to compete in the highland games :P
[/end of fun reply :P]

Sauron - 9-11-2008 at 04:47

I see. So you are going to hydrolyze a few dozen kg of hair so you can do a better job of tossing a caber?

At least you got the tossing part right.

kazaa81 - 9-11-2008 at 06:05

get easy, I think he just needs a simple answer like
reflux hairs with conc. HCl for some time then neutralize
the acidity with NaHCO3,
something in the lines of that thread chemoleo's posted :)

16MillionEyes - 26-2-2009 at 20:20

If you're planning on having hair as a vitamin supplement be sure to know that unless you are using reagent grade materials (which often times are not intended for consumption anyway due to high concentrations of trace materials relative to toxicity levels) you are going to probably book yourself a room in a hospital before you get there. The other thing is that keratins aren't particularly nutritious due to the high concentrations of a few AAs similar to most gelatins (collagen), so your AAs supplement are going to have to come from somewhere else anyway.

To sum it up, try a vitamin store. Cooking up your hair on base isn't going to boost up your meal.