In Vitro Protection by Crataegus microphylla Extracts Against Oxidative Damage and Enzyme Inhibition Effects

Crataegus species have been used as food and also in folk medicine for the treatment of various diseases. The present study aimed to make investigations on the biologic properties of different extracts prepared from Crataegus microphylla C. Koch, which was collected from Turkey.

Dried leaf, stem bark, and fresh fruit samples of C. microphylla were separated and ethanol extract, acidified (0.5% HCl, pH: 2.5) ethanol extract, ethanol:water (1:1) extract, methanol extract, acidified (0.5% HCl, pH: 2.5) methanol extract, methanol:water (1:1) extract, water extract, and acidified (0.5% HCl, pH: 2.5) water extract were prepared for each. Various biologic effects such as the prevention of oxidative DNA damage, acetylcholinesterase, tyrosinase, α-glucosidase inhibition, and antioxidant effects with 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, PRAP, and FRAP assays of these extracts at different concentrations were studied.

Acidified methanol extract of stem barks exhibited the highest acetylcholinesterase and tyrosinase inhibitions among the other extracts with IC₅₀ values of 204.02±0.95 μg/mL and 37.30±0.27 μg/mL, respectively. Acidified ethanol extract of leaves was the most efficient extract against α-glucosidase, giving an IC₅₀ of 15.78±0.14 μg/mL. The IC₅₀ value of the acidified ethanol extract for DPPH was 9.89±0.09 µg/mL. Methanol extracts of leaves and stem barks at the dose of 125 µg/mL exhibited significant protective activity against DNA strand scission by hydroxyl radicals (.OH) on supercoiled pBR322 DNA.

Acidified methanol or ethanol extracts prepared with stem bark and leaf from C. microphylla have potential antioxidant, hypoglycemic, and neuroprotective effects.