SPECTROPHOTOMETRIC DETERMINATION OF OILS WITH RADICALS OF CONJUGATED OCTADECATRIENOIC ACIDS

At chromatographic separation of substances with different chromophores using spectrophotometric detection, instead of preliminary calibration of the detector response to inaccessible (or hardly accessible) standard samples, an approach specific for triacylglycerines (TAG) is proposed. According to this approach, a wavelength similar to the isosbestic point (278 nm) was found for the TAG containing radicals of three types of isomeric conjugated octadecatrienoic acids (COA), which can be used to determine the ratio of the amounts of TAG with isomeric radicals without introducing correction factors for sensitivity of each substance. The procedure of mathematical processing of UV spectra of TAG containing COA radicals which allows detecting these points is proposed. The specificity of the TAG composition allows us to abandon the detection or use of highly labile individual compounds. The method is developed on the example of the seed oil of centranthus (“red valerian”, Centranthus DC.), the TAG of which are formed by two isomeric COA (a- and b-eleostearic) and pomegranate seed oil (Punica granatum L.) with radicals of another pair of COA (punicic and a-eleostearic).

масло семян, триацилглицерины, Centranthus, Punica granatum, Momordica charantia, УФ спектр, высокоэффективная жидкостная хроматография, a-элеостеариновая кислота, b-элеостеариновая кислота, пуниковая кислота, аналоги изобестических точек, seed oils, triacylglycerols, Centranthus, Punica granatum, Momordica charantia, UV spectrum, HPLC, a-eleostearic acid, b-eleostearic acid, punicic acid, isosbestic point analogue

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