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Truth is a will o’ the wisp that can only be caught in the net of glory-scorning experiment.
In science, being first counts for everything. Being second to make a discovery carries little more prestige than copying a great work of art. The early twentieth century was the first time that a scientist could garner enough glory to make racing to be first worthwhile. Vitamins, a hot topic to scientists and to the public, provided the arena for well-publicized contests. Being the first to purify and chemically characterize a vitamin would bring academic prestige and public recognition. The effort consequently attracted investigators with big ambitions and egos to match.
THE TASK OF THE BIOCHEMIST
By the 1920s, the scientific community had accepted that scurvy resulted from a dietary deficiency of a substance essential for life but required in minuscule amounts. “Vitamin” had prevailed as the name for that kind of nutrient, but vitamins were defined only by their biological activity. There was a substance that prevented beriberi and another that prevented scurvy. Their chemical properties were understood only in broad strokes, and their molecular structures were unknown.
Vitamin C was the substance in citrus juice and many other fruits and vegetables that prevented scurvy. It was water soluble, acidic, and more stable in acidic than basic solutions. It lost potency—that is, its ability to prevent scurvy—with heating or when exposed to air. But exactly what it was—what atoms it contained, how those atoms were arranged into a molecule, how it could be commercially manufactured—remained a mystery.
One of the prominent investigators of the time, Sylvester Solomon Zilva (who understandably went by S. S. Zilva) said, “The ground was now prepared for the task of the biochemist.”1 For the biochemists to do their job properly, they needed pure vitamin C, meaning crystals of the compound. And getting those crystals proved to be a challenge. The general strategy was to start with plant material—lemon juice, for example—and try to progressively remove contaminating substances. At each step, the researchers tested what remained to verify that it still contained vitamin C. Although lemon juice was the richest known source of vitamin C, it had two disadvantages. First, it contains far greater quantities of contaminating sugars than of the vitamin. The chemical properties of the vitamin were so similar to the sugars that separating them proved difficult. Second, the vitamin was unstable in lemon juice and rapidly lost its potency when exposed to air.
In addition, the only method available for detecting vitamin C, termed a biological assay, was to test the ability of material to prevent or cure scurvy in animals, most conveniently, guinea pigs. The investigator placed groups of guinea pigs on a scurvy-inducing diet, usually a cereal grain known to contain the antiberiberi vitamin B supplemented with butterfat or milk fat to provide vitamins A and D. The test substance was added to that diet, and the investigator observed its ability to either prevent or cure scurvy.
For a quantitative assay, multiple groups of animals had to be used, each group receiving a different amount of the test substance. The assay was time consuming, as it took three to four weeks for guinea pigs to develop scurvy. In addition, it was imprecise and expensive, but the investigators had no alternative until a chemical assay could be developed, and a chemical assay required knowing what the substance was.
Two laboratories, one in Europe and one in the United States, attacked the problem head-on. S. S. Zilva started working on vitamin C in 1918 at the Lister Institute in London.2 He worked for fifteen years and came close to purifying vitamin C from lemon juice, but he never quite reached his goal. He removed the solids and precipitated the citric acid from the juice, retaining the vitamin C activity in the remaining solution. Working at low temperatures and progressively precipitating various contaminants out of the solution, he obtained almost pure vitamin C. However, the antiscorbutic substance remained unstable, and he could never crystalize the pure compound.
Charles Glen King at the University of Pittsburgh also started with lemon juice. He achieved the goal but did not get the credit. That story requires a detour through Hungary.
A LUCKY MAN
The man who did receive the credit for purifying vitamin C was the biochemist Albert Szent-Gyorgyi.3 He was born in Budapest to an upper-middle-class family with an aristocratic heritage—his full name was Albert Imre Szent-Gyorgyi von Nagyrapolt. Early in his career, he kept the aristocratic von, signing himself Albert von Szent-Gyorgyi, but he soon gave it up. The pronunciation of his name is close to the English Saint Georgy, and he was content with being called that or merely “Saint George” by those intimidated by the Hungarian spelling.
His colorful and peripatetic life later included working as an undercover agent during World War II to help Hungary avoid the ravages of the Nazi occupation.
On the one hand, my inner story is exceedingly simple, if not indeed dull: my life has been devoted to science and my only real ambition has been to contribute to it and live up to its standards. In complete contradiction to this, the external course has been rather bumpy.4
Despite the bumps in his personal life, his professional life was to benefit repeatedly from extraordinary good fortune.
He began his scientific career working in the anatomy laboratory of his uncle, Mihaly Lenhossek, the most prominent Hungarian medical researcher of the time. Lenhossek wanted his nephew to study diseases of the rectum. Albert was unenthusiastic about the rectum, but he was sufficiently interested in medicine to earn his medical degree from the University of Budapest. He graduated just as World War I broke out and was immediately was conscripted into military service and sent to the front lines. He apparently did not enjoy being a soldier, since he shot himself in the arm to escape the army. Following the war, when Czechoslovakia invaded Hungary in 1919, he packed up and, with wife and daughter in tow, moved from city to city across Europe, working in one temporary research position after another.
He eventually secured a position as a chemist in a laboratory at Groningen in the Netherlands, where he developed an interest in biological oxidation in both plants and animals. He started with the seemingly trivial question of why some fruits and vegetables turn brown when their cut flesh is exposed to air, whereas others retain their pale color. Examining this latter group, he found that they contained a reducing substance, something that protected their flesh from oxidation. He could not know it at the time, but the unknown antioxidant was vitamin C. Based on entirely erroneous speculation that this substance was a hormone, he also looked for the same activity in the adrenal gland, where he found it in large quantities. He later mused, “I must admit that most of the new observations I made were based on wrong theories.” And, one might add, lucky guesses.
When the head of his laboratory in Groningen died, Szent-Gyorgyi once again had to move on. And once again he landed on his feet, securing a fellowship at Cambridge University with the help of the prominent professor of physiology, Frederick Gowland Hopkins, who became his mentor.
While in Cambridge, Szent-Gyorgyi succeeded in crystallizing a small amount of his reducing substance from oranges as well as from lemons and cabbages. The substance was a carbohydrate that had properties resembling a sugar. When he submitted his paper to the Biochemical Journal, he proposed the name “Ignose,” since he was ignorant of what it was and -ose is the ending for the chemical names of sugars. The editor of the journal did not share Szent-Gyorgyi’s sense of humor; he also rejected “Godnose.” Szent-Gyorgyi and the editor finally agreed on “hexuronic acid,” as it contained six carbon atoms and was acidic.5
Hopkins sent some of the material to S. S. Zilva at the Lister Institute. Inexplicably, Zilva reported that the material was not vitamin C. Zilva never explained the basis for this conclusion, but coming from a highly regarded expert, his pronouncement carried a great deal of weight.
Szent-Gyorgyi could purify hexuronic acid in large quantities only from adrenal glands, which were not readily available in Cambridge. So in 1929 he once again pulled up stakes and went to the Mayo Clinic in Minnesota, where he had access to the slaughterhouses in St. Paul. He crystalized twenty-five grams of the material and sent half to Walter N. Haworth, a carbohydrate chemist in Birmingham, England, to determine its chemical structure. Haworth could not complete the structural chemistry with the quantity of compound provided. Possibly deterred by Zilva’s assertion that hexuronic acid was not vitamin C, Szent-Gyorgyi put the project on the back burner.
In 1931, Szent-Gyorgyi accepted the chair of medicinal chemistry at the University of Szeged in his hometown in Hungary, taking with him his remaining supply, about one gram, of hexuronic acid. Soon after he arrived, Joseph Svirbely, an American of Hungarian heritage, walked unannounced into the laboratory in Szeged and offered his services to determine if hexuronic acid was vitamin C. Svirbely had just earned his PhD in the laboratory of Charles Glen King, the nutrition researcher at the University of Pittsburgh and Szent-Gyorgyi’s rival. Svirbely came to Hungary on an Institute of International Education fellowship.
One of Szent-Gyorgyi’s strokes of luck was that this young man appeared out of the blue. Svirbely had gained experience in the biological assay for vitamin C in King’s laboratory. Like S. S. Zilva in London, King was trying to purify vitamin C from lemon juice. He and Svirbely had published a paper reporting their early results using the assay.6 Svirbely, exploiting his experience with the assay, used Szent-Gyorgyi’s last gram of hexuronic acid to test whether hexuronic acid was the antiscorbutic vitamin.
He divided guinea pigs into four groups. One group, the “positive controls,” received a scurvy-inducing diet of rolled oats, bran, butterfat, salts, and a small amount of milk powder. They all died of scurvy after an average of twenty-six days. Another group received the same basal, scurvy-inducing diet as the positive controls but were supplemented with one milliliter per day of lemon juice, an amount known to prevent scurvy. They remained healthy. A third group received a standard laboratory diet, and they also remained healthy. The crucial “test animals” received the basal, scurvy-inducing diet plus one milligram of hexuronic acid per day.
The question was whether pure hexuronic acid would prevent scurvy just as well as lemon juice. The answer was that it did. Hexuronic acid was vitamin C.
Svirbely and Szent-Gyorgyi laid out their evidence.7
- A tiny amount of pure hexuronic acid, roughly twice the amount in a milliliter of lemon juice, was as good as the lemon juice itself or a standard laboratory diet in preventing scurvy.
- Hexuronic acid was contained in a variety of foods in proportion to their content of vitamin C.
- The chemical properties of hexuronic acid coincided with the known properties of vitamin C.
- The chemist Norman Haworth attested to the purity of Szent-Gyorgyi’s hexuronic acid.
S. S. Zilva, disappointed to have been beaten to the finish line, continued to publicly demur, but the conclusion was inescapable. Szent-Gyorgyi’s hexuronic acid was vitamin C.8
Szent-Gyorgyi later said that he had long suspected that hexuronic acid was vitamin C but had never tried to test it. He enjoyed the chemistry laboratory but avoided animal research. Also, he found vitamins “theoretically uninteresting.” He wrote dismissively, “What one has to eat is the first concern of the chef, not the scientist.”9 But it was vitamin C that propelled him to scientific prominence.
A CONTESTED RACE
While Szent-Gyorgyi and Svirbely were working in Hungary, C. Glen King in Pittsburgh was pursuing the same goal: to show that hexuronic acid was vitamin C. The race ended in a dead heat.
King was a biochemist who became interested in vitamins after reading the work of Hess and Fish on infantile scurvy in New York City. He was a careful and well-trained researcher and an expert in the bioassay of vitamin C. He purified hexuronic acid from lemon juice, but he also may have gotten some that was prepared from animal adrenal glands by Szent-Gyorgyi’s former colleague Edward C. Kendall at the Mayo Clinic. King found that hexuronic acid was vitamin C at about the same time as Szent-Gyorgyi.
The virtual tie created a public fight over who was first. American supporters of King went up against European colleagues of Szent-Gyorgyi. Pittsburgh was the Silicon Valley of its time, creating new industries that were disrupting old ways of doing business. The upstarts in the blue-collar city in the hills of Pennsylvania felt that they were being disrespected in favor of a Hungarian aristocrat backed by Oxbridge insiders.
The fight came down to two versions of the detailed chronology of events. King had written to his trainee Svirbely in mid-March saying that he had tentatively concluded that hexuronic acid was vitamin C but was holding off on publication until he was sure of the purity of his hexuronic acid preparation. He also may have wanted to check out the claim of another investigator that vitamin C was a derivative of narcotine, a compound found in poppies and chemically unrelated to hexuronic acid. In early March, shortly before King mailed his letter, Svirbely had written from Hungary to his former mentor telling him that he and Szent-Gyorgyi had shown unequivocally that hexuronic acid was vitamin C. The two letters may have crossed in the transatlantic mail.
Svirbely’s letter apparently prodded King into submitting a report to the American journal Science to establish priority. His paper, published in the issue dated April 1, 1932, announced that hexuronic acid and vitamin C were identical. Thus, King in fact published first. However, his publication in Science provided no experimental details.10 He submitted a complete manuscript with details of his experiments to the Journal of Biological Chemistry a month later, on May 9, 1932.11
Szent-Gyorgyi, upon seeing the letter from King, dashed off a report to Nature, the European equivalent of Science.12 The paper appeared in the April 16, 1932, issue and stated the same conclusion as King—that hexuronic acid is vitamin C—but with the important difference that it included Svirbely’s guinea pig bioassay results to back up the claim. Thus Szent-Gyorgyi and Svirbely were the first, by less than a month, to publish unequivocal evidence that hexuronic acid was the antiscorbutic factor. The scientific community, at least in Europe, assumed that King had not wrapped up all his loose ends by the time he sent the letter to Science and credited Szent-Gyorgyi with being first.
King disputed this version of the chronology. He said that he had in fact completed his experimental work prior to mailing his letter to Science. One can understand that he felt cheated. He had worked for years on purifying vitamin C and had done persistent, careful science. If he had been second to the finish line, it was only by a couple of weeks. He had trained Svirbely, who abruptly ran off to Hungary to join the laboratory of his major competitor. Rubbing more salt in King’s wounds, Szent-Gyorgyi not only professed to be uninterested in vitamins but disparaged the entire field.
In addition, while King was toiling away in Pittsburgh, Szent-Gyorgyi came to the answer as much through good luck as good science. This is a common story. Luck is important in science, but a scientist must have the judgment, intelligence, and drive to exploit the good luck if he or she is to garner the praise. Szent-Gyorgyi had them all.
Svirbely in subsequent interviews was not forthcoming about his motives in moving to Hungary nor about the exact chronology of events. Some speculated that he suspected that hexuronic acid was vitamin C but was frustrated by the inability to get pure material in King’s laboratory. Therefore he jumped ship and joined Szent-Gyorgyi, who he knew had the pure compound. King no doubt felt that his trainee had stabbed him in the back.
The dispute left enduring scars on all involved. Szent-Gyorgyi never felt comfortable speaking before audiences in the United States, where the popular press had portrayed him as a usurper. King carried a grudge for the rest of his career, and Svirbely never dispelled suspicions of disloyalty to his mentor.
CRYSTALS FROM PEPPERS
Szent-Gyorgyi and King had shown that hexuronic acid was the antiscorbutic vitamin C, but they still did not know its chemical structure. Svirbely’s experiments had exhausted Szent-Gyorgyi’s meager supply. In Hungary, Szent-Gyorgyi had no access to adrenal glands in large numbers, but as luck would have it—and Szent-Gyorgyi never lacked for luck—Szeged was the center of the Hungarian paprika industry. Szent-Gyorgyi later told the story (perhaps apocryphal) that one evening, when entertaining an especially boring dinner guest, his wife served fresh paprika peppers.13 Szent-Gyorgyi did not feel like eating the peppers or enduring the dinner-table conversation. He escaped out the back door, peppers in hand, and retreated to his lab to test them for hexuronic acid. He labeled this act “a husband’s cowardice.”
Whether or not the story is true, paprika proved to be a rich source of vitamin C. Importantly, the vitamin C in ground-up paprika is much more stable than in citrus juice. Szent-Gyorgyi promptly turned his laboratory into a paprika processing assembly line, and he soon crystallized enough hexuronic acid to allow Norman Haworth, his chemist collaborator in Birmingham, to determine its molecular structure.14 At the suggestion of a colleague, they changed the name from hexuronic acid to ascorbic acid, as it was the antiscorbutic factor.15
For this work, Szent-Gyorgyi received the Nobel Prize in Physiology and Medicine in 1937, and Haworth the Nobel Prize in chemistry the same year.16 This rekindled the dispute over who had been the first to show that hexuronic acid was vitamin C. The local Pittsburgh press was especially incensed at what it saw as a miscarriage of academic justice. The Pittsburgh Post-Gazette claimed to have proof that King, not Szent-Gyorgyi, was the first to show that hexuronic acid was vitamin C, and they made Svirbely the villain. According to the newspaper, “not until a student of Dr. King’s, Dr. J. L. Svirbely, carried the knowledge gained in King’s laboratory across the ocean to Gyorgyi’s laboratory did Gyorgyi discover vitamin C and go on to win the 1937 Nobel Prize in medicine.” Svirbely denied disclosing secrets to Szent-Gyorgyi.
King was superficially gracious. He said that perhaps Szent-Gyorgyi had deserved the Nobel Prize not just for vitamin C but for the totality of his work on metabolism. However, in the same breath he cited a letter to Science by a nutritionist at the Mellon Institute, a nearby Pittsburgh institution, which again laid out a chronology that awarded priority for the discovery of ascorbic acid to King.17
To his credit, Szent-Gyorgyi did not seek a patent on his discoveries or his method for preparing ascorbic acid from paprika, which later became the commercial source of the vitamin. He provided ascorbic acid to other scientists and to supplement the nutrition of children who lived in northern latitudes and suffered vitamin deficiency in the winter. He did, however, patent and manufacture a canned spread for one’s morning toast made from paprika and rich in vitamin C. He first named it “Vita-prik” but changed the name to “Pritamin” when friends explained why it did not sell well in English-speaking countries.
Szent-Gyorgyi began to proselytize the benefits of the vitamin. He turned from disparaging nutrition research to touting vitamin C as the answer to multiple health problems. With his newfound scientific prominence, he had speaking engagements throughout Europe and used them as opportunities for “preaching vitamin C,” as he put it. As a harbinger of things to come, he advocated, with no animal data and without success, for a clinical trial to test ascorbic acid in preventing colds and infections in babies.
Hoping to follow up on his success with vitamin C, Szent-Gyorgyi became interested in antioxidant compounds termed bioflavonoids, which are found in many foods. He dubbed them “vitamin P” and claimed they could cure colds and confer many other benefits. These claims did not pan out, and he eventually turned his attention elsewhere. He went on to a productive career investigating cellular metabolism and the mechanism of muscle contraction. In contrast to his professional success, his personal life remained bumpy; he had a penchant for changing wives as well as jobs.
Charles Glen King moved to Columbia University, where he continued his distinguished career in biochemistry. Joseph Svirbely returned to Pittsburgh for a few years and then engaged in toxicology research for US government laboratories. He kept detailed records of his work on vitamin C, including press clippings, but he never explained his motivation for moving from Pittsburgh to Szeged.
This story is a prime example of the role of serendipity in science. If Szent-Gyorgyi had not wandered into the right laboratories in his peripatetic travels across Europe after World War I, if Svirbely had not walked into his laboratory in Szeged, if Szent-Gyorgyi had not escaped a boring dinner guest to go his laboratory, paprika peppers in hand, and if those peppers had not been a gold mine of vitamin C, it is likely that Szent-Gyorgyi never would have completed the race, much less won. In science, as in sports, sometimes winning is more a matter of luck than skill. But as Szent-Gyorgyi’s story also demonstrates, it requires a nimble mind to exploit good fortune.
Once the chemical identity of vitamin C was known and ascorbic acid was produced commercially, scientists could apply the burgeoning armamentarium of biochemical techniques to understand its role in physiology and metabolism. This was normal science, and it illustrates the power of that endeavor. Paradigm shifts are not required to make large strides in understanding nature. Even though no more Nobel Prizes have been awarded for vitamin C, it has been a period of tremendous progress.