Thursday, October 2, 2008

Kidney Juice



What to do with your morning, um, lemonade. Sell it to your neighborhood chemist.

I learned in my studies of Rome this year that in the heyday of that Empire, urine was prized as a valuable ingredient for washing clothes and collected from the public privies for that purpose.

I remember that during my sophomore year of high school, I proudly announced to the class during an oral report, my discovery that Ladies of Rome used lion wee-wee to bleach Their hair.

Yeah, I was that kind of kid.

Most of us wannabee scientists are aware that synthetic urea (natural urea, converted from ammonia, being a major constituent of your daily offering to the porcelain god, because it is a good way to get rid of excess nitrogen) is highly valuable in the production of a number of products, such as explosives, plastics and as a flavor additive to cigarettes.

From wikipedia:
“[Urea, aka carbamide] was the first organic compound to be artificially synthesized from inorganic starting materials, in 1828 by Friedrich Wöhler, who prepared it by the reaction of potassium cyanate with ammonium sulfate . .. thus starting the discipline of organic chemistry.

This discovery prompted Wöhler to write triumphantly to a friend:

"I must tell you that I can make urea without the use of kidneys, either man or dog. Ammonium cyanate is urea."

Happy day for him.

Today I learned more strange facts about kidney juice. Seems that most mammals have the ability to break urea down (oxidize it) into a substance called allantoin. Synthetic allantoin is, like urea, quite a useful product. It’s probably in your mouthwash, toothpaste or lipstick.

But humans and higher apes have lost the ability to convert urea into allantoin.
More details: http://en.wikipedia.org/wiki/Uric_acid

That doesn’t seem to bother us too much, (does it bother you?) but I wonder why evolution took that step, evolution usually having a good reason for what it does. Related to this seems to be our loss of the ability to make our own citric acid (vitamin C), which most animals can do and which can be a very bad thing, as ye olde timey sailors learned the hard way. Evolution screwed up on that detail.

I had a guinea pig for a pet as a kid, and I learned then that humans share that latter defect with those furry little critters.

Very strange.

4 comments:

Chase March said...

What an interesting post. I didn't know that.

Eastcoastdweller said...

I tell you, Chase, there's so much odd stuff out there to learn. Sometimes I just take a word, an ordinary word, like apple or sturgeon or Canada ((o:) and follow it where it leads.

And sometimes where it leads is fascinating.

bulletholes said...

In the Civil War, Southern women saved their urine to make Niter for gunpowder.
Lost anyway.

Eastcoastdweller said...

Bulletholes: I did not know that, about this War of Northern Aggression of which you speak. (o: