Prunus the skin than in the flesh. They also contain moderate levels of carotenoids and ascorbic acid. Peaches and nectarines are orange and yellow in color which can be attributed to the carotenoids present. Ascorbic acid is important in hydroxylation reactions, such as collagen synthesis and de novo synthesis of bone and cartilage, and wound healing. Ascorbic acid is also a precursor of Vitamin C, which is essential for repairing tissues and absorbing iron. Various "Prunus" species are winter hosts of the Damson-hop aphid, "Phorodon humuli", which is destructive to hops "Humulus lupulus" just at the time of their maturity, so
Chemistry of ascorbic acid from animal adrenal glands. In 1932 Charles Glen King confirmed that it was indeed the antiscorbutic factor. In 1933, sugar chemist Walter Norman Haworth, working with samples of "hexuronic acid" that Szent-Györgyi had isolated from paprika and sent him in the previous year, deduced the correct structure and optical-isomeric nature of the compound, and in 1934 reported its first synthesis. In reference to the compound's antiscorbutic properties, Haworth and Szent-Györgyi proposed to rename it "a-scorbic acid" for the compound, and later specifically -ascorbic acid. Because of their work, in 1937 the Nobel Prizes for chemistry and medicine were awarded to