ANALYSIS OF CHANGES IN THE PARAMETERS OF THE NON-ENZYMATIC ANTIOXIDANT SYSTEM OF HIGHER PLANTS UNDER THE INFLUENCE OF POLYCHLORINATED BIPHENYLS

Osinkina Tatyana Vladimirovna

The article presents the results of a model experiment to assess the impact of PCBs: Sovol solution (a mixture of tetra-, penta- and hexa-PCBs) in concentrations of 0.0005; 0.001; 0.0012 mg/l on plants of the species annual sunflower (Heliánthus ánnuus) and shepherd's purse (Capsella bursa-pastoris (L.) Medik). The material for the study was sprouts, leaves and flowers of the studied plants of different ages. The content of pigments and hydroxycinnamic acids was determined in the samples by the spectrophotometric method, for lycopene and β-carotene against n-hexane, for chlorogenic and caffeic acids against ethyl alcohol. The aim of the work was to analyze the effect of PCBs on the indices of the non-enzymatic antioxidant system of annual sunflower (Heliánthus ánnuus) and shepherd's purse (Capsella bursa-pastoris (L.) Medik) in a model experiment. For sunflower, by the flowering period, the amount of chlorogenic acid increased by 62 times, caffeic acid by 13.5 times. The increase in the content of β-carotene and lycopene was also characterized by positive dynamics: for β-carotene, the values varied within 0.0077-1.987 mg/l, for lycopene 0.0037-1.943 mg/l. By the time of flowering, the content of β-carotene increased by 25.8 times, lycopene by 22.3 times. The content indicators for hydroxycinnamic acids in shepherd's purse (Capsella bursa-pastoris (L.) Medik) increased from the seedling stage to flowering: for chlorogenic acid within 0.005-0.07%, for coffee acid 0.005-0.089%. Based on the excess of lycopene in comparison with β-carotene, it follows that lycopene slowly cyclizes into β-carotene and, therefore, acts in the plant, apparently, together with antioxidant enzymes and hydroxycinnamic acids under the influence of elevated concentrations of PCBs - 0.001 mg / l and 0.0012 mg / l. It has been shown that PCBs affect the amount of β-carotene and lycopene even in the case of low concentrations of PCBs during their initial entry into the plant.

Keywords:lycopene, β-carotene, chlorogenic acid, caffeic acid, polychlorinated biphenyls, toxicants, shepherd's purse, sunflower