In the 1920s and 1930s, Dr. Albert Szent-Györgyi, a Hungarian professor of medicinal chemistry, made some very important discoveries that help us to understand basic nutrition. While conducting a series of early experiments on citrus plants, he found that plant browning could be caused by peroxidase, a plant enzyme that is active during oxidation. By adding citrus juice to peroxidase, the browning process could be stopped. In his experiments he isolated a substance he called, hexuronic acid that he thought was active within citrus juice. This was one of the first steps in the discovery of what we know today as vitamin C. Szent-Györgyi, also conducted experiments on guinea pigs, which are similar to humans, in that they have to consume hexuronic acid to remain healthy. He decided to rename hexuronic acid to ascorbic acid or vitamin C, reflecting its anti-scorbutic (scurvy fighting) properties. It took many years to find a way to produce large amounts of ascorbic acid from natural sources. It was by chance he found the answer in his dinner! The story goes that he did not want to eat the paprika in his dinner, so he took it to his laboratory, where he found it to contain large amounts of vitamin C. Without his discovery we would not know that vitamin C is important for proper functioning of our immune system. By eating our daily dose of fruits and vegetables, which contain vitamin C, we improve the repair and growth of tissue and many more factors that keep us healthy. Szent-Györgyi was awarded the Nobel Prize in Physiology or Medicine in 1937 for his discovery of vitamin C. He is also known for his later contribution to what we know as the Citric Acid (Krebs) cycle.