| Summary: | Susceptibility of soybean phosphatidylcholine, 1,2-dipalmitoyl-<i>sn</i>-glycero-3-phosphocholine (DPPC) and its phosphono analogue (<i>R</i>)-2,3-dipalmitoyloxypropylphosphonocholine (DPPnC) towards selected lipases and phospholipases was compared. The ethanolysis of substrates at <i>sn</i>-1 position was carried out by lipase from <i>Mucor miehei</i> (Lipozyme<sup>®</sup>) and lipase B from <i>Candida antarctica</i> (Novozym 435) in 95% ethanol at 30 °C, and the hydrolysis with Lecitase<sup>TM</sup> Ultra was carried out in hexane/water at 50 °C. Hydrolysis at <i>sn</i>-2 position was carried out in isooctane/Tris-HCl/AOT system at 40 °C using phospholipase A<sub>2</sub> (PLA<sub>2</sub>) from porcine pancreas and PLA<sub>2</sub> from bovine pancreas or 25 °C using PLA<sub>2</sub> from bee venom. Hydrolysis in the polar part of the studied compounds was carried out at 30 °C in acetate buffer/ethyl acetate system using phospholipase D (PLD) from <i>Streptococcus</i> sp. and PLD from white cabbage or in Tris-HCl buffer/methylene chloride system at 35 °C using PLD from <i>Streptomyces chromofuscus</i>. The results showed that the presence of C-P bond between glycerol and phosphoric acid residue in DPPnC increases the rate of enzymatic hydrolysis or ethanolysis of ester bonds at the <i>sn</i>-1 and <i>sn</i>-2 position and decreases the rate of hydrolysis in the polar head of the molecule. The most significant changes in the reaction rates were observed for reaction with PLD from <i>Streptococcus</i> sp. and PLD from <i>Streptomyces chromofuscus</i> that hydrolyzed DPPnC approximately two times slower than DPPC and soybean PC. The lower susceptibility of DPPnC towards enzymatic hydrolysis by phospholipases D gives hope for the possibility of using DPPnC-like phosphonolipids as the carriers of bioactive molecules that, instead of choline, can be bounded with diacylpropylphosphonic acids (DPPnA).
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