Abstract
Objective
The present study aimed to quantify and identify the bioactive compounds of the Arbutus unedo L. leaves in order to evaluate both their antioxidant properties and litholytic activities against calcium oxalate stones.
Methods
This survey was carried out using hydroalcoholic extract (E.FA) and infusion (I.FA) of A. unedo leaves. The quantification of phenolic compounds, flavonoids, flavonols
and anthocyanins was done by spectrophotometric methods and
identification of chemical components was performed by ultra-performance
liquid chromatography with photodiode array and electrospray ionization
tandem mass spectrometry. Antioxidant activity was measured using the
1,1-diphenyl-2-picrylhydrazyl (DPPH) method and by the ferric
reducing/antioxidant power (FRAP) assay. Litholytic activity of E.FA and
I.FA was studied using a special model that resembles circuitry of the
urinary system.
Results
E.FA showed greater antioxidant efficacy than I.FA (P < 0.05).
Its higher efficiency was shown via the values of median inhibitory
concentration, which was close to (76.14 ± 0.91) μg/mL for E.FA versus
(202.64 ± 5.77) μg/mL for I.FA using the DPPH method, and (53.77 ± 0.81)
μg/mL for E.FA versus (236.86 ± 31.90) μg/mL for I.FA, using FRAP
method. I.FA exhibited significantly higher litholytic activity compared
to E.FA (P < 0.05), with dissolution values of 31.03% ± 0.63% versus 14.55% ± 0.65%, respectively.
Conclusion
Overall, the results suggest that the A. unedo is rich in bioactive compounds, and possesses antioxidant and litholitic abilities that are worthy of further study.