Products of the Reaction of Cholesterol with Hypochlorite Anion

K. T. Momynaliev,^1,2 S. V. Osipova,¹ V. L. Sadovskaya,³ V. M. Govorun,¹ and V. I. Sergienko¹

¹Institute of Physico-Chemical Medicine, Russian Ministry of Health Care and Medical Products, ul. Malaya Pirogovskaya 1a, Moscow, 119831 Russia; fax: (7-095) 246-45-01.

²To whom correspondence should be addressed.

³Institute of Agricultural Biotechnology, Russian Academy of Agricultural Sciences, ul. Timiryazevskaya 42, Moscow, 127550 Russia.

Submitted July 9, 1996; revision submitted August 20, 1996.

Products of the reaction of cholesterol with hypochlorite (OCl^-) in various systems (egg phosphatidylcholine liposomes, low-density lipoproteins, and aqueous colloidal dispersion of cholesterol) were separated and analyzed by TLC, HPLC, and gas chromatography--mass spectrometry. The reactions of hypochlorite with cholesterol result in the same reaction products in all treated systems. Eighteen fractions were isolated from the reaction mixture by normal-phase HPLC in hexane--isopropanol (95:5 v/v); these were then examined by gas chromatography--mass spectrometry. Six products less polar than cholesterol were isolated from the reaction mixture; two of them were identified as 4,6-cholesten-3-one and 4-cholesten-3,6-dione. Among the oxidation products more polar than cholesterol, nine compounds were identified; they are 5,7-cholestadien-3beta-ol, 3,5-cholestadien-7-one, 4-cholesten-3beta,6beta-diol, 5-cholesten-3beta,7beta-diol, cholestan-3beta,5alpha,6beta-triol, 5alpha-cholestan-3beta-ol-6-one, 5-cholesten-3beta-ol-7-one, 5alpha,6alpha-epoxycholestan-3beta-ol, and 5alpha-cholesten-3,6-dione.

KEY WORDS: cholesterol, sodium hypochlorite, oxidation, HPLC, gas chromatography--mass spectrometry, phospholipids.

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