Biological effects and chemical characterization of Iris schachtii Markgr. extracts: A new source of bioactive constituents

This study gathers information about the effects of different extracts (methanol and water) from rhizomes and aerial parts of Iris schachtii on selected enzymes (cholinesterases, alpha-amylase and alpha-glucosidase, tyrosinase and lipase) as well as of their antioxidant capacities and antimutagenic properties in relation with their phenolic composition. The chemical composition was assessed by determining total phenolic and flavonoid content as well as individual phenolic compounds by HPLC-DAD. Moreover, antioxidant abilities of the investigated extracts were tested by using different assays including free radical scavenging (DPPH and ABTS), reducing power (CUPRAC and FRAP), phosphomolybdenum and metal chelating, overall rhizomes being indicated as a superior source of antioxidant compounds. HPLC analysis revealed the abundance of some phenolics including apigenin (2584 μg/g extract) and luteolin (2510 μg/g extract) in aerial parts extracts while rhizomes were rich in apigenin (4734 μg/g extract) and kaempferol (4214 μg/g extract). The methanolic extracts exhibited a high anti-lipase activity while all extracts presented a relatively high inhibition on α-glucosidase. Furthermore, interactions between dominant compounds from extracts and selected enzymes were investigated by molecular modeling studies in order to explain at a molecular level the interactions between selected compounds and active sites of the enzyme/s.