antioxidants Article LC-MS Profile, Gastrointestinal and Gut Microbiota Stability and Antioxidant Activity of Rhodiola rosea Herb Metabolites: A Comparative Study with Subterranean Organs Daniil N. Olennikov 1,* , Nadezhda K. Chirikova 2, Aina G. Vasilieva 2 and Innokentii A. Fedorov 3 1 Laboratory of Medical and Biological Research, Institute of General and Experimental Biology, Siberian Division, Russian Academy of Science, 6 Sakh’yanovoy Street, Ulan-Ude 670047, Russia 2 Department of Biology, Institute of Natural Sciences, North-Eastern Federal University, 58 Belinsky Street, Yakutsk 677027, Russia;
[email protected] (N.K.C.);
[email protected] (A.G.V.) 3 Institute for Biological Problems of Cryolithozone, Siberian Division, Russian Academy of Science, 41 Lenina Street, Yakutsk 677000, Russia;
[email protected] * Correspondence:
[email protected]; Tel.: +7-9021-600-627 Received: 26 May 2020; Accepted: 14 June 2020; Published: 16 June 2020 Abstract: Golden root (Rhodiola rosea L., Crassulaceae) is a famous medical plant with a one-sided history of scientific interest in the roots and rhizomes as sources of bioactive compounds, unlike the herb, which has not been studied extensively. To address this deficiency, we used high-performance liquid chromatography with diode array and electrospray triple quadrupole mass detection for comparative qualitative and quantitative analysis of the metabolic profiles of Rhodiola rosea organs before and after gastrointestinal digestion in simulated conditions together with various biochemical assays to determine antioxidant properties of the extracts and selected compounds. R. rosea organs showed 146 compounds, including galloyl O-glucosides, catechins, procyanidins, simple phenolics, phenethyl alcohol derivatives, (hydroxy)cinnamates, hydroxynitrile glucosides, monoterpene O-glucosides, and flavonol O-glycosides, most of them for the first time in the species.