Feed additive Vitamin d3 Crystal Vitamin d3 powder is a derivative of steroids and a
general term for compounds with similar structures that have the ability to
promote normal bone growth and maintenance. At present, it is known that there
are at least ten sterol substances with vitamin D activity, of which only two
are more important, known as pre vitamin D. One is ergosterol, also known as
calciferol or ergocalciferol, which is produced by sunlight or ultraviolet
radiation from plant oil or yeast. Another is 7-dehydrosterol, which exists in
the skin and is converted into vitamin D3 under light, also known as
cholecalciferol. The structures of D2 and D3 are very similar, both of which
are B-ring opening derivatives of precursor sterols. The difference between the
two is that there is an additional double bond and a methyl group on the side
chain of vitamin D2.
Vitamin D2 and D3 are colorless crystals,
with corresponding m.p. values of 115-118 ℃ and 84-85 ℃. They are
insolub…