Possibilities of the biochemiluminiscence method with a model environment from blood serum in assessing the antioxidant activity of plant materials

Antioxidant activity (AOA) is an important indicator of the evaluation of plant raw materials (RM), which are widely used in medicine to obtain various medicines. The use of RM at the present stage of the pharmaceutical industry development allows avoiding large-scale production of synthetic medicines, accompanied by a negative impact on the environment. For an objective assessment of AOA, it is necessary to apply methods that allow determining not only the content of the active substance, but also generally characterizing the functional activity of RM. The article presents data on the AOA of aqueous extracts from the leaves and fruits of Hippophae rhamnoides L., Aronia melanocarpa L. The determination of antioxidant activity was performed by biochemiluminiscence (BСHL) using serum from white mongrel rats as a model environment (MЕ). The evaluation criteria were the maximum intensity (Imax) and the light sum of the glow (S). The results obtained were compared with the data of the analysis of BCHL without ME, as well as with the data of alternative methods for quantifying the antioxidant potential of RM (coulometric titration, direct titration, spectrophotometry). According to the criteria for assessing the intensity of free radical oxidation (Imax) using the BCHL method without ME, it was found that aqueous extracts from the leaves and fruits of A. melanocarpa, as well as H. rhamnoides leaves, have a high antioxidant potential (343, 274 and 268 mV, respectively), and from H. rhamnoides fruits – more short. BCHL results showed that the amount of radicals in blood serum decreased upon contact with extracts from vegetable raw materials. Among the studied samples, extracts from the fruits of A. melanocarpa were characterized by the highest AOA (S=2006±137 mV·s). At the same time, according to alternative methods, they occupy an intermediate position in terms of the quantitative content of biologically active substances (BAS) with antioxidant properties. Based on the weak correlation between the data of the BСHL method and alternative methods for determining AOA, it is concluded that it is necessary to take into account the possibility of an indirect relationship between the content of BAS in RM and the effect manifested in conditions as close as possible to biological systems. The measurement of AOA by the BСHL method is actually an assessment of the function, as well as the effectiveness of BAS, and complements quantitative methods for assessing the antioxidant activity of ME.