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5 December 2013 11:26 am ,
Vol. 342 ,
An animal rights group known as the Nonhuman Rights Project filed lawsuits in three New York courts this week in an...
Researchers have been hot on the trail of the elusive Denisovans, a type of ancient human known only by their DNA and...
Thousands of scientists in the Russian Academy of Sciences (RAS) are about to lose their jobs as a result of the...
Dyslexia, a learning disability that hinders reading, hasn't been associated with deficits in vision, hearing, or...
Exotic, elusive, and dangerous, snakes have fascinated humankind for millennia. They can be hard to find, yet their...
Researchers have sequenced and analyzed the first two snake genomes, which represent two evolutionary extremes. The...
Snake venoms are remarkably complex mixtures that can stun or kill prey within minutes. But more and more researchers...
At age 30, Dutch biologist Freek Vonk has built up a respectable career as a snake scientist. But in his home country,...
- 5 December 2013 11:26 am , Vol. 342 , #6163
- About Us
The Carotene Kid
21 April 1999 4:00 pm
Paul Karrer, a Swiss organic chemist famous for his work with vitamins and natural dyes, was born on this day in 1889.
Karrer studied the chemistry of plant pigments, including anthocyanins, xanthophylls, and carotenoids. He showed that carotene--the yellow, orange, or red color in fruits and vegetables--came in two forms and that one of them, beta-carotene, was a precursor to vitamin A.
By 1930, Karrer had worked out the chemical structures of carotene and vitamin A, which he finally succeeded in synthesizing in 1950. Karrer also solved the structures of vitamin B-2 (riboflavin), vitamin E (alpha-tocopherol), and vitamin B-12. For these achievements he shared the 1937 Nobel Prize in chemistry. Karrer's organic chemistry textbook, Lehrbuch der Organischen Chemie, published in 1930 and translated into five languages, became a standard reference book for several generations of chemists.