"Elixir
By Theresa Levitt
(Harvard, 314 pages, $32.95)
In the mid-1830s two ambitious Parisian chemists, Edouard Laugier and Auguste Laurent, set out to answer a question that had perplexed scientists for centuries. By day they worked at a perfume house, Laugier Pere et Fils, distilling cakes of bitter almonds, crushed bergamot peel and bitter oranges for tonics and fragrances. But by night, the men conducted radical experiments hoping to discover the chemical difference between organic and inorganic material -- and in so doing, find the secret of life itself.
"Elixir" by Theresa Levitt, a history professor at the University of Mississippi and author of "A Short Bright Flash: Augustin Fresnel and the Birth of the Modern Lighthouse" (2013), vividly evokes cultural life in Bohemian Paris, the turbulence of the French Revolution and its aftermath, and the feuds that plagued rival scientists. At times it would help to have a degree in organic chemistry to get easily through some of the denser scientific passages in this book. But Ms. Levitt's social history, especially of perfume, is fascinating.
For centuries perfume was seen as a protection from disease, which was thought to be transmitted through miasmas of infected air. As Ms. Levitt writes: "The only indication of these invisible infections was smell, and thus the best way to preserve health and extend life was to purge one's environment of these bad smells." Bathing, particularly in hot water, was considered a dangerous invitation to sickness.
During Louis XIV's long reign, Versailles reeked of perfume. At the court of his successor, Louis XV, even the fountains ran with the stuff. It was the single greatest expense of the household of his favorite mistress, Madame de Pompadour. Ms. Levitt states that "the vast resources poured into supplying the court with perfumes can be seen as an effort to hoard the essence of life itself." In 1791, two years after the Revolution had broken out, Marie Antoinette planned to take her stores of perfume bottles when she escaped from the palace. A servant, noticing that the queen's supply was packed and ready to go, alerted the mayor of Paris.
Napoleon went through 60 bottles of perfume a month. "He doused himself in it," Ms. Levitt writes, "bathed in it, carried a handkerchief scented with it, and even splashed some on the face of a man having a fit in front of him. He drank it, diluted with water or wine, and kept a bottle beside him on the eve of every battle. It was, he insisted, a necessary source of health and vitality." Now that hot water was no longer thought to be a danger, he became addicted to baths, and like Winston Churchill many years later, held meetings as he relaxed in the tub. Often an unfortunate aide was obliged to read him his letters in the bathroom, squinting through the steam.
In the 1820s, less than a decade after Napoleon's final defeat and exile, a young chemist named Edouard Laugier lived above the family's perfume house in the center of Paris. One of his main tasks was distilling the essence of bitter almonds -- poisonous to eat -- from pressed cakes. Greeks, Romans and Arabs had used a paste of bitter almonds to rejuvenate the skin and over 3,000 years later it was keeping faces youthful at the court of Versailles.
Popular elixirs sold by Laugier Pere et Fils, prized for their therapeutic value, included Eau de Melisse, made with lemon balm and lavender, and Queen of Hungary water, scented with rosemary. The house signature was the plant-based Eau Regeneratrice. It could be imbibed or applied to the skin and claimed to be an effective treatment for just about anything from memory loss and gout to pimples.
Laugier befriended Auguste Laurent, the son of wine merchants, who was a talented artist and musician although he had trained as a mineralogist and hoped to become an academic chemist. Soon he and Laugier began experimenting in a lab in the back of the perfume shop. One of Laugier's accomplishments was the invention of a distiller called a "dephlegmator," which in Ms. Levitt's description sounds like a Rube Goldberg machine. "A tall vertical column divided into a number of different levels by a series of 'trays' . . . a kind of helical purgatory, where at each stage the soul of the distillate was weighed and judged."
The two men had a tough time gaining acceptance from the scientific community. It was tightly controlled by those who still revered the work of Antoine Lavoisier, a rich tax collector who had introduced precise formulas into chemistry in 1787, replacing its antiquated language. (He subsequently lost his head in the Revolution.) Among hundreds of changes: oil of vitriol became sulfuric acid, spirit of Venus was renamed acetic acid, and crystals of the moon became the less heavenly silver nitrate.
Since the ancient Greeks, scientists had believed that living matter had a spirit. By the 19th century, however, the prevailing consensus was that the building blocks of both living and non-living matter were the same. Laurent and Laugier were not convinced. For their ideas they were treated as outcasts, ignored or ridiculed. Laurent in particular is a tragic figure, a brilliant man publicly humiliated (he made a sketch of himself plunging head first into the Seine). He died penniless of tuberculosis at the age of 45.
One person who believed in Laurent and Laugier was a young lab assistant, Louis Pasteur. They had demonstrated that even when molecules were chemically identical, there were structural differences between those that were occurring naturally and those that were synthetic. Later, Pasteur was to show that their thesis was correct. Biochemists are still searching for the key to this anomaly.
Among the many pleasures of "Elixir" are Ms. Levitt's serendipitous stories, from the critical soap "famine" in 1793, to the invention of a new "delightful beverage," bottled soda. Her quirkiest account concerns the 1834 Exhibition of Industry in Paris where Laugier Pere et Fils were placed in a gallery of "sensory arts," next to the carpet section. The biggest draw was a rug made from the skins of hundreds of cats stitched together. A steal at 10,000 francs.
---
Ms. Hodgson is the author of "It Seemed Like a Good Idea at the Time: My Adventures in Life and Food."" [1]
Why only L-amino acids are found in living things?
"L-amino acids are found because we, living creatures, have enzymes which can only recognize L-confomation and that is also true for D-carbohydrates which can be recognized by specific enzyme during metabolism."
The active center of an enzyme can only function by binding and fixing the transition state of substrates, thereby increasing the likelihood that the reaction will occur more quickly. For that, the active center of an enzyme has to fit the transition state like a glove fits a hand. Mirror-symmetric D-amino acids and L-carbohydrates are not suitable for such enzymes. That requirement does not exist in reactions that occur in non-living nature, because there are no such enzymes.
1. The Scientific Smell of Success. Hodgson, Moira.
Wall Street Journal, Eastern edition; New York, N.Y. [New York, N.Y]. 06 June 2023: A.13.
Komentarų nėra:
Rašyti komentarą