The basidial tree fungus Inonotus obliquus (chaga) of the order Hymenochaetales is widely used in world medicine, as it is characterised by anti-inflammatory and antioxidant effects, and is effective in oncological, infectious and invasive diseases, as well as in diabetes, obesity, fatigue, liver and kidney pathologies, etc. However, the toxicological properties of chaga, which grows in Ukraine, require scientific justification. The aim of this study was to establish the parameters of acute toxicity of the aqueous extract of the basidial tree fungus Inonotus obliquus, which was obtained in natural conditions in Ukraine. The study was conducted on white Wistar rats according to generally accepted methods for conducting preclinical studies of new drugs. It was established that the LD50 of the test substance for rats after intragastric administration is 8959 mg/kg according to the method of G. Kerber, 9,175.0 mg/kg according to the method of G. Pershin, and 9,175.0 mg/kg according to the method of B. Shtabsky – 8,890 (6,510.1 ÷ 11,269.9) mg/kg. According to the results obtained, it can be stated that the extract of the basidial wood fungus Inonotus obliquus, according to the classification of chemical substances by degree of danger (interstate standard 12.1.007-76), corresponds to class IV, and according to the classification of substances by toxicity – class V and the degree of toxicity “practically non-toxic substances”. The established pathoanatomical changes, such as acute catarrhal gastritis, catarrhal-hemorrhagic or hemorrhagic enteritis, acute venous hyperemia of internal organs, dilatation of the wall of the right ventricle of the heart, edema of the subcutaneous tissue and skeletal muscles in the area of the right part of the scapula, manifested themselves identically in the body of the dead rats of the experimental groups and correlated with the dose of the studied extract. Determination of acute toxicity parameters is a prerequisite for studying the pharmaco-toxicological properties of medicinal substances, therefore the obtained results are promising for further preclinical and clinical studies with the aim of scientifically substantiating the use of medicinal raw materials from Inonotus obliquus obtained in Ukraine in veterinary medicine
chaga, preclinical studies, laboratory animals, pathological changes, pharmacological effect
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