২৬ নভেম্বর, ২০০৫

Tedious seasonal news reports.

I have a rule: I change the channel/click the mouse when I see the word "tryptophan."

১০টি মন্তব্য:

chuck b. বলেছেন...

So, will you be deleting all comments on the tryptophan post, or just ignoring them?

Kidding! Just kidding.

Actually, what bugs me about tryptophan is how people have come to mispronounce it...even chemists who should know better. It's trip-ta-fane, not fan.

Ah well. Noone sheds a tear for the glum pedant.

From a chemist's perspective at least, tryptophane is interesting for its indole ring moiety, also found in LSD, strychnine, serotonin, vinblastine, and psilocybin. The Feds restrict nine indole-containing drugs, a few of which are quite similar to tryptophan.

Ann Althouse বলেছেন...

I am so, so impossibly sick of hearing people murmur about how eating turkey is like taking a drug. It's more annoying than people going on about getting high on sugar because it's so predictably going to be trotted out at Thanksgiving.

It's another entry for my modern day "Dictionary of Received Ideas":

Thanksgiving: Turkey contains tryptophan.

Palladian বলেছেন...

chuck, I've never given much thought to the indole ring inside tryptophan, though it's interesting since I just got a small quantity of indole for use in my perfumery experiments. Indole is a small but significant part of a lot of scents, most importantly jasmine, and is used in perfumery quite a bit. It's amazing that something so foul (indole smells overwhelmingly like feces) in high dilution smells light and floral. I had no idea that it was the functional group of Trp.

By the way, the tryptophan levels in turkey are generally not any higher than those in chicken or even beef. The reason people get tired after Thanksgiving dinner is the plateful of baked yams with miniature marshmallows, the side of mashed potatoes spewing gravy from its caldera, the four thousand peas covered with butter sauce, the jiggling mound of cranberry relish, the half a pumpkin pie, all washed down with a couple quarts of hard cider.

নামহীন বলেছেন...

eating turkey is like taking a drug Um, not a suppository I hope.

Say, I would really, truly like to encourage you to "give back to the community" by having a weekly "Ask the Con Law Prof" post in which readers could pose you well perhaps just about any question and you would answer or riff off the constitutional implications. Tonight I would point you to Deborah Davis who was arrested for not showing her ID to the Feds while on a public bus in Denver. Does she have a case? What advice would the con law prof have to give to her ACLU defenders?

Because this is offtopic, I really am not asking you to address this. But though this is offtopic, I would really like to encourage your participation in a weekly "Ask the Con Law Prof posting."

Done right, it could be encouraged for all professionals "Ask the Corporate Attorney Blogger", "Ask the Tort Law Prof", "Ask the MD Blogger", "Ask the Economics Prof", "Ask the Engineer Prof".... And you would get an entry on your wikipedia page saying you started it!!!! Win win!

chuck b. বলেছেন...

Palladian, I don't remember whether or not I've worked with simple indole before, but I don't doubt that it smells terrible! All those little rings containing nitrogen smell terrible (except for the obvious example of imidazole [the side chain group of the amino acid histidine] which has no odor that I'm aware of).

I was surprised any small alkaloid would find its way into perfumery experiments. So surprised, in fact, I googled this to check it out, and sure enough, you're right. :)

I understand pleasant-smelling esters find no place in perfume because body sweat hydrolyzes them to stinky acids. Too bad...there are some nice esters.

Olefins (carbon-carbon double bonds) make for some interesting smells. Cyclohexane has a nice enough solvent smell, but put a double bond in it and you get unbearable cyclohexene.

Palladian বলেছেন...

chuck, there are a couple of esters in use in perfumery. In case you're interested, here's a list of many of the commonly used chemicals in perfumery. These are usually used along with some naturals (essential oils and solvent extracted essences of plants, fruits and flowers) to compose perfumes. Studying perfumery has certainly stretched my already thin chemistry knowledge.

If you've never read the book "The Emperor of Scent", I recommend it. It tells the story of a biophysicist named Luca Turin who is also a perfume fanatic and his quest to publish his new (and quite possibly correct) theory of human olfaction. I've had lunch with Dr Turin, he's quite amazing, now building new molecules to replace known allergens among the perfumery chemicals.

Ann Althouse বলেছেন...

Palladian: You've reminded me of the real reason I'm irritated by people claiming to be high on tryptophan. They used to openly admit they ate too much and were lolling about because they'd been gluttons. Now, they act like they're having a more refined experience. They've lost touch with the absurd vanity of the claim.

Chuck and Palladian: I love the science details!

Quxxo: You don't realize how much research and study is involved in answering legal questions. But I like getting links to news articles that raise legal questions. I might blog about them, but not necessarily answer the questions.

Goatwhacker বলেছেন...

Actually, what bugs me about tryptophan is how people have come to mispronounce it...even chemists who should know better. It's trip-ta-fane, not fan.

Chuck, my initial degree was in chemistry and I ended up in the medical field, and I've always heard it pronounced trypto-fan, not fane. According to the dictionary it can be pronounced either way. Maybe it's one of those mispronunciations that become so widespread they're considered acceptable. Possibly there are are regional variations?

chuck b. বলেছেন...

Goatwhacker: You are certainly correct. In all my years as a chemist, I can only recall a few people pronouncing it fane--one biochemist, one organic chemist and one non-scientist linguist. I also recall the pronunciation of tryptophan discussed in the back of an issue of Chemical and Engineering News. At any rate, as I said, I was being pedantic.

Palladian: All I know about perfumery is what I recall chemistry textbooks mentioning in asides. You're right; there are lots of esters on that list. Any chemical that ends in "-ate" is an ester.

Besides indole, I recognize many absolutely rank-smelling chemicals on that list. Furfuryl mercaptan?! Perhaps some chemicals function like salt for the nose. Too much salt ruins a dish, but cooks use it lightly to "marry the flavors".

Palladian বলেছেন...

chuck: Your metaphor about salt in cooking is apt. Many perfumery compounds are absolutely foul smelling when undiluted; they are used in tiny percentages in perfumes to adjust certain qualities, but never as perceptible components in the composition. Some perfumes have hundreds of separate ingredients, many of them only .01% of the composition, so a dash of isobutyric acid becomes a component of chamomile, not rotting milk! It's kind of awful being the perfumer dripping these from their bottles. That's what assistants are for!