[Anea98]

Hi everibody,

I need to optimize an extraction procedure for vitamin K1 and vitamins D2 and D3.

The results I am obtaining suggest that the addition of a very small amount of water (1% in a mixture composed of 9% EtOH and 90% CO2) improves significally the recovery for vitamins D but not for vitamin K. I am trying to explain that. Both are fat-soluble vitamins so this improvement should not be observed.

Is it possible that water can idrolize the double bonds of vitamins D increasing the solubility in ethanol? I believe this is more difficult to happen for vitamin K1 because the double bond included in the aromatic system if very stable becouse of the cheto-enol tautomerism. I am not sure about the double bond in the aliphatic chain, can the idrolization occur? Is that position too sterically encumbered? And if the idrolization occur, is it enough to make vitamin K1 polar enough to be more soluble in EtOH?

Thanks in advance to anyone who will try to help me.