The effect of oil base on the stability of dissolved microbiological carotene

Abstract

[3-Carotene is one of the important nutritional elements (provitamin A). Recent years have been marked by its growing application in different fields of practical medicine. A new burst of interest has been raised by recent studies suggesting that it may be used as a prophylactic medication against oncological afflictions, in particular, those induced by radiation [ 1 3]. It was suggested that 13-carotene performs as a bioantioxidant in lipid components of biological membranes by accepting free radicals and the singlet oxygen [4]. Thus, carotene controls the peroxide oxidation of lipids in normal and pathological conditions in a way similar to the action of other antioxidants, in particular, tocopherols [5]. The molecule of 13-carotene is characterized by an extended system of conjugated double bonds. This explains the high activity of this compound in reactions with free radicals. Because of the same reason, carotene is extremely unstable in the atmosphere of oxygen [6]. The oxidation of polyenes has been extensively studied for retinol acetate and its analogs, sea buckthorn (Hippophae) carotinoids, and dog rose (Rosa canina) carotinoids because these substances are used in the manufacture of pharmaceutical preparations and feedstock with high vitamin A activity [7 9]. Methods were proposed to evaluate the stability of vegetable oils by the rate of their oxidation under definite conditions; a kinetic method of evaluation of the content of natural and synthetic antioxidants in complex multicomponent systems (e.g., natural lipids) was also elaborated [I0]. Vegetable oil solutions of microbiological carotene are the most common carotene-containing preparations [11, 12]. Fatty-acid components of vegetable oil triglycerides show a marked tendency to oxidation; as a result, hydroperoxides (which are a source of free radicals) accumulate and the content of tocopherols concomitantly decreases. Therefore, it is