Biography
Biography: Ain Raal
Abstract
Vitamin C is a well-known antioxidant, the deficiency of which leads to scurvy, accompanied with osteoporosis and severe anemia. During the Leningrad Blockade (1941-1944), the scientists worked to extract vitamin C from Scots pine (Pinus sylvestris L.) needles to cure and prevent the outbreaks of scurvy. Since 1930, it was believed that leaves of cowslip (Primula veris L.) contain up to 5.9% ascorbic acid and one leaf was enough to fulfill the recommended daily intake of vitamin C. Such enormous content of ascorbic acid could be the result of titrimetric assay technique used in those days. In the present study, the content of ascorbic acid was determined by slightly modified European Pharmacopoeia HPLC method for quantification of related substances in ascorbic acid. Actually, the content of ascorbic acid in P. sylvestris needles was just from 0.0005% to 0.0067% in dry material. In fresh cowslip, leaves were collected with weekly interval with the content of ascorbic acid varied from 1.2 to 2.4%. The recommended daily intake should be 20-30 fresh cowslip leaves. Spinach, parsley and rucola are poor sources of vitamin C; practically unreal amount of their fresh salad (300-500 g) can fulfill the recommended daily intake of vitamin C. Commercial orange juices contain ascorbic acid from 9-50 mg/100 ml, depending on producer one to five glasses of juice could fulfill the recommended daily intake of vitamin C. On chromatograms of Goji berries (Lycium spp.), we were not able to identify the peak of ascorbic acid.