Vitamin d In 1922, vitamin d was found in fish liver oil In 1930, vitamin D, ergocalciferol) was isolated In 1932, vitamin D3 cholecalciferol) was isolated only difference between two vitamins is that there are a methyl group and a double bond on side chain of vitamin D2Vitamin D • In 1922, vitamin D wasfound in fish liver oil. • In 1930, vitamin D2 (ergocalciferol) wasisolated. • In 1932, vitamin D3 (cholecalciferol) wasisolated. • Only difference between two vitamins is that there are a methyl group and a double bond on side chain of vitamin D2