Evaluation of Biological Activity and Phenolic Compounds of Cardaria draba (L.) Extracts

Abstract

"The antibacterial, antioxidant, anti-inflammatory and scolicidal activities, as well as phenolic compounds from various leaf and seed extracts of Cardaria draba (L.) Desv. (whitetop) were examined. The antibacterial activity against two Grampositive bacteria (Staphylococcus aureus and Bacillus subtilis) and two Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli) was evaluated by the agar well diffusion method. Antioxidant activity was assayed by using the seed and leaf extracts on synthetic DPPH free radicals and assessing their capacity to inhibit the peroxidation of linoleic acid. Anti-inflammatory activity was investigated by protein denaturation. The viability of Echinococcus granulosus protoscolices was investigated by evaluating their motility under a light microscope. Phenolic compounds in leaf and seed extracts were analyzed by HPLC. Our result showed that the MICs of various C. draba extracts against bacterial strains ranged from 3 to 134 μg/mL. The maximum and minimum MIC values for S. aureus were 3 μg/mL for the ethanolic leaf extract (ELE) and 86 μg/mL for the aqueous seed extract (ASE), respectively. Results of antioxidant assays showed that the ethanolic seed extract (ESE) had a significantly higher antioxidant capacity than ELE, and that both extracts had significantly lower antioxidant capacity than BHA and ascorbic acid. Results of the anti-inflammatory assay showed that as the concentration of extracts and control increased, there was a concomitant increase in the percentage inhibition of protein denaturation. ELE (500 μg/mL) and ESE (100 μg/mL) showed maximum and minimum percentage inhibition of protein denaturation (90% and 48%, respectively). Scolicidal activity and percentage mortality increased with exposure time, but the level depended on the extract concentration. In total, 16 compounds were identified from both extracts. Isorhamnetin (13.85%), quercetin (12.9%), and kaempferol (11.5%) were most abundant compounds in ELE, while the most abundant compounds in ESE were caffeic acid (13.3%), p-coumaric acid (7.9%), sinapic acid (7.9%), and ellagic acid (7.9%). These results support the therapeutic potential of C. draba."