Mountain ash (Sorbus aucuparia L.) is a valuable medicinal and food plant that is widely used in practical medicine and in amateur horticulture. The purpose of this study was to determine the content of ascorbic acid, organic acids, tanning substances and flavonoids in the fruits of some representatives of the Sorbus genus of the collection of the South-Ural Botanical Garden-Institute and to identify the most promising taxa. For analysis, fruits were collected in the full ripening phase and dried to air-dry state. Phytochemical studies were carried out according to conventional methods. The object of comparison was the official pharmacopoeia species – Sorbus aucuparia. Analysis of the obtained data found that the fruits × Sorbocotoneaster pozdnijkovii and Sorbus sibirica outperformed the natural form (Sorbus aucuparia) in terms of ascorbic acid content by 11.54 and 43.27%; Organic acids by 24.11 and 60.84%; Tanning substances by 3.49 and 43.23%; Flavonoids by 44.19 and 12.79%, respectively. The obtained results allow to recommend these taxa as promising sources of raw materials for production of biologically active substances in production of natural food products and food additives.

The purpose of this study was to determine the content of carotenoids in the fruits of some representatives of Sorbus genus from the collection of the South Ural Botanical Garden-Institute. For the quantitative analysis, the fruits of the rowan trees were collected in the phase of full ripening and dried to an air-dry state. Sorbus aucuparia L. was used as an object of comparison as the official pharmacopoeias species. Qualitative detection of carotenoids was performed by thin layer chromatography, quantitative determination - spectrophotometrically.It was found that the highest content of carotenoids is characterized by a sort of hybrid origin × Crataegosorbus miczurinii “Garnet” – 46.41 mg/% and a natural hybrid Sorbocotoneaster pozdnijkovii – 42.64 mg /%. The minimum content of this group of substances is noted in the raw material of Sorbus frutescens (0.86 mg/%) with white fruits. This fact is confirmed by the presence of plant pigments – carotenoids, in fruits that have a yellow-orange-red color. The local Sorbus aucuparia had a low carotenoid content (11.24 mg/%).The study, with a certain degree of reliability, suggests the presence of carotenoids in the fruits of the rowan trees studied and allows us to recommend them as a promising source of raw materials for the production of vitamin-active drugs and food additives. The studied taxons × Crataegosorbus miczurinii and × Sorbocotoneaster pozdnijkovii are characterized by high introduction resistance under the conditions of the Bashkir Cis-Urals. In the future, it is intended to continue the study of other members of the Sorbus genus for the presence of pharmacopoeias properties.