Inhibition of Digestive Enzymes and Antioxidant Activity of Extracts from Fruits of <i>Cornus alba</i>, <i>Cornus sanguinea</i> subsp. <i>hungarica</i> and <i>Cornus florida</i>–A Comparative Study

• Main Authors: Joanna Truba, Iwona Stanisławska, Marta Walasek, Wioleta Wieczorkowska, Konrad Woliński, Tina Buchholz, Matthias F. Melzig, Monika E. Czerwińska
• Format: Article
• Language: English
• Published: MDPI AG 2020-01-01
• Series: Plants
• Subjects: siberian dogwood; polyphenols; digestive enzymes; diabetes; obesity
• Online Access: https://www.mdpi.com/2223-7747/9/1/122

The fruits of some <i>Cornus</i> species (dogwoods) are used in traditional medicine and considered potential anti-diabetic and hypolipemic agents. The aim of the study was to determine the ability of extracts from <i>Cornus alba</i> (CA), <i>Cornus florida</i> (CF), and <i>Cornus sanguinea</i> (CS) to inhibit digestive enzymes namely <i>&#945;</i>-amylase, pancreatic lipase, and <i>&#945;</i>-glucosidase, as well as isolation of compounds from plant material with the strongest effect. In addition, the phytochemical profile and antioxidant activity of extracts from three dogwoods were compared with HPLC-DAD-MS/MS and DPPH scavenging assay, respectively. Among the aqueous-ethanolic extracts, the activity of <i>&#945;</i>-amylase was the most strongly inhibited by the fruit extract of CA (IC₅₀ = 115.20 &#177; 14.31 &#956;g/mL) and the activity of <i>&#945;</i>-glucosidase by the fruit of CF (IC₅₀ = 38.87 &#177; 2.65 &#956;g/mL). Some constituents of CA fruit extract, such as coumaroylquinic acid, kaempferol, and hydroxytyrosol derivatives, were isolated. Among the three species of dogwood studied, the greatest biological potential was demonstrated by CA extracts, which are sources of phenolic acids and flavonoid compounds. In contrast, iridoid compounds or flavonoid glycosides found in fruits of CF or CS extracts do not play a significant role in inhibiting digestive enzymes but exert antioxidant activity.