Qualitative and Quantitative Analysis of Ukrainian Iris Species: A Fresh Look on Their Antioxidant Content and Biological Activities

Abstract

The major groups of antioxidant compounds (isoflavonoids, xanthones, hydroxycinnamic acids) in the rhizome methanol extracts of four Ukrainian Iris sp. (Iris pallida, Iris hungarica, Iris sibirica, and Iris variegata) were qualitatively and quantitatively analyzed using HPLC-DAD and UPLC-MS/MS. Gallic acid, caffeic acid, mangiferin, tectoridin, irigenin, iristectorigenin B, irisolidone, 5,6-dihydroxy-7,8,3′,5′-tetramethoxyisoflavone, irisolidone-7-O-β-d-glucopyranoside, germanaism B, and nigricin were recognized by comparing their UV/MS spectra, chromatographic retention time (tR) with those of standard reference compounds. I. hungarica and I. variegata showed the highest total amount of phenolic compounds. Germanaism B was the most abundant component in the rhizomes of I. variegata (7.089 ± 0.032 mg/g) and I. hungarica (6.285 ± 0.030 mg/g). The compound analyses showed good calibration curve linearity (r2 > 0.999) and low detection and quantifications limit. These results validated the method for its use in the simultaneous quantitative evaluation of phenolic compounds in the studied Iris sp. I. hungarica and I. variegata rhizomes exhibited antioxidant activity, as demonstrated by the HPLC-ABTS system and NRF2 expression assay and anti-inflammatory activity on respiratory burst in human neutrophils. Moreover, the extracts showed anti-allergic and cytotoxic effects against cancer cells. Anti-coronavirus 229E and lipid formation activities were also evaluated. In summary, potent antioxidant marker compounds were identified in the examined Iris sp.

The Comparative Analysis of Carboxylic Acid Composition of Four Iris Species from Ukraine

“…Malic, citric, tartaric, oxalic acids take part in the metabolism of carbohydrates and amino acids and the maintenance of acid‐base balance in the human body. These effects are mainly due to the antioxidant action, i. e., inhibition of lipid peroxidation and inhibition of free radical stages of prostaglandin synthesis [10] …”

“…Flora of Ukraine is composed of 16 species [9] . According to our previous studies, extracts of Ukrainian Iris species exhibit antioxidant, [10] antibacterial, antitumor, [11] antiexcudative, [12] and anticancer activities [13] . Individual compounds and extracts from Iris spp.…”

“…Rhizomes of irises are rich sources of secondary metabolites such as flavonoids, [16,17] isoflavonoids and their glycosides, [9,10,14,15] xanthones, [15,16,18] quinones, [19] triterpenoids, [20,21] carboxylic acids, [22–24] and stilbene glycosides [16] . Recent studies confirmed presence of various secondary metabolites in leaves of species of this genus: xanthones, hydroxycinnamic acids, isoflavonoids, [16,17] flavonoids, [15,16,25] fatty acids, [11] quinones, tannins, saponins and terpenoids [21,26] .…”

Phytochemical research and anti-inflammatory activity of the dry extracts from northern highbush blueberry leaves

“…Superoxide is a major radical produced by neutrophils while elastase belongs to major components of azurophilic granules [34] and their uncontrolled amount contributes to several acute and chronic diseases, including sepsis, ARDS, lung injury, arthritis or psoriasis [36]. These markers of neutrophilic inflammation were shown to be affected by several plant extracts [31].…”

“…Elastase release representing the degranulation from azurophilic granules was evaluated as described before [30]. Experimental conditions have been described in detail earlier [31].…”