Sciencemadness Discussion Board

Metabolization of hairs?

kazaa81 - 25-2-2006 at 19:45

Hello all,

I would like to know how hairs are metabolized by the human digerent apparatus.
Hairs are rich of amino acids, so can't they be an integrator of them?

Thanks for help

chemoleo - 26-2-2006 at 14:52

I thought hairs are *not* digestible, by humans at least. The reason, to my knowledge, is because the structure of hair is very compact, and does not expose peptide bonds to proteases, which would normally 'digest' protein structures.

From Wiki:
Quote:

Hair consists 90% of a biological polymer, α-keratin, and about 10% water, which modifies its mechanical properties. This α-helically coiled protein is further wound into supermolecular coiled-coil microfibrils, many of which are held together with a protein glue to form long macrofibrils, which are packed inside dead hair cells about 100 µm long by 3 µm across. Several of these associate to form one strand of hair, which is covered with tiny surface scales. The ends of individual keratin chains are high in the amino acids proline (an α-helix breaker) and cysteine. Adjacent keratin chains are held together by many disulfide bonds bridging their cysteines. These links are very robust; virtually intact hair has been recovered from ancient Egyptian tombs. Different parts of the hair have different cysteine levels, leading to harder or softer material.
Hair is strong. A single strand can hold 100g (3.5oz) of weight. A head of hair could support 12 tonnes. It is equivalent in strength to aluminium or Kevlar. Wet hair, however, is very fragile.


The strength of Aluminium! :o

Anyway, this confirms this, it is so stable because the structure is heavily crosslinked, and supercoiled, and does not allow easy steric access to proteases.

Darkblade48 - 26-2-2006 at 19:10

I think there was a thread created awhile back (sorry, I don't remember who actually carried out the experiment), but it involved extracting the cysteine from hair (I believe that was the experimental)

I do recall that it involved a lengthy reflux though, so I doubt human stomachs could digest hair :)

Interestingly enough, humans can get the equivalent of a hair ball in their digestive system, and this causes for concern since the human body can't get rid of it

thanks all!

kazaa81 - 28-2-2006 at 05:24

Thanks all for replying!
In fact, I tought that hairs where strong to digest! :o

So, if one would take something nutritionally useful from hairs, how can one do this? I mean something eatable (so, if the experiment need strong acids & bases, one must carefully wash away them!).

Please share ideas! Amino acids are good for everyone!

unionised - 5-3-2006 at 13:15

Find something that eats hair (like moth larvae) ; feed the hair to the larvae. Eat them!:D

kazaa81 - 6-3-2006 at 05:08

Please don't make stupid posts like this...

I meant to de-polymerize the keratin to aminoacids (like refluxing in strong HCl), then neutralize the substances "not good" for your body (of course strong acids & bases aren't good for it) and then...you can eat without risk your aminoacids.

DrP - 6-3-2006 at 07:07

QUOTE:
'Please don't make stupid posts like this...'

I know unionised was only joking but it's not as stupid as it sounds. The Inuits (I think it's the Inuits anyway) let reindeer eat a type of braken which is indigestable to humans - then they eat the partially digested braken from the dead reindeers stomach.

pneumatician - 30-10-2014 at 10:43

dry distillation