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FIGURE 8.1 Vitamin C, also known by the chemical name of L-ascorbic acid, has the chemical formula C6H8O6.

Nonetheless, the Scottish naval surgeon James Lind working two centuries later is often credited with the first description that citrus fruit can cure scurvy.1-4 This was prompted by the disastrous voyage of George A. Anson, whose circumnavigation of the globe resulted in the death of over half of his sailors from scurvy. The subsequent classic experiments of Lind in 1747 proved the efficacy of lemon juice to prevent the disease. The wide acceptance of the recommendation to provide a lemon juice and later a lime juice ration aboard ship led to the "limey" nickname for the British sailors. Capt. James Cook compulsively employed these measures as well as others to successfully demonstrate that prolonged sea voyages need not result in scurvy. These successes continued to be ignored by some, leading to rampant scurvy among soldiers of the American Civil War and even to the tragic demise of Robert Scott's South Pole expedition in 1912.

It was not until the 20th century that the chemical nature of the active ingredient of these food sources was understood. It became apparent that only certain species, such as man and the guinea pig, needed this factor that could either prevent or cure scurvy. Working independently, Szent-Gyrogyi and King identified this antiscorbutic factor. Identified as hexuronic acid, it was later named ascorbic acid by Szent-Gyrogyi, who was awarded the Nobel Prize for his work in 1937.1-4

Vitamin C, or chemically, L-ascorbic acid, has the chemical formula C6H8O6 (Figure 8.1). It is derived from D-glucuronic acid conversion to D-gluconic acid and then to L-glulonolactone and finally to ascorbic acid in animals. In animals such as man, nonhuman primates, capybaras, Indian fruit bats, bulbuls, swallows, trout, salmon, locusts, and guinea pigs, it is the inability to complete this last step in the synthesis process that requires vitamin C to be provided in the diet.1,5,6 It is available in a wide variety of fresh fruits and vegetables. However, due to its relative chemical instability, vitamin C is less available in preserved foods. Thus, the hospitalized patient on a limited diet, a sailor at sea, or a geriatric patient on a minimal income is at greater risk of deficiency than the individual on a mixed fresh diet.

Ascorbic acid deficiency is characterized by hemorrhage, hematological alterations, impaired wound healing, depressed immune functions, and psychological distur-bance.1-4,7 The deficiency state of scurvy and its effect on wound healing is probably best described by George Anson, a British commodore in the 1740s, who wrote "a most extraordinary circumstance (occurred) . . . the scars of old wounds, healed for ascorbic acid deficiency

How To Reduce Acne Scarring

How To Reduce Acne Scarring

Acne is a name that is famous in its own right, but for all of the wrong reasons. Most teenagers know, and dread, the very word, as it so prevalently wrecks havoc on their faces throughout their adolescent years.

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