Phytochemical Screening, Antioxidant and Anti-inflammatory Activities of Polyphenolic Extracts of Strawberry-tree Fruits (Arbutus unedo L)

Arbutus unedo L., is an evergreen plant belonging to the Ericaceae family, an endemic species of the Mediterranean flora. The aim of this study was to characterize the polyphenolic extract of A. unedo fruits with phytochemical analysis followed by evaluation of antioxidant and anti-inflammatory activities. Antioxidant activity was determined using the scavenging activity of DPPH free radical and ferric-reducing antioxidant power assay. Then, the anti-inflammatory potential of A. unedo extracts was evaluated using Human Red Blood Cells (HRBC) membrane stabilization, and egg albumin denaturation assays. The highest total phenolic, flavonoid, and tannin content was recorded in the methanolic extract with 61.96 ± 5.33 mg GAE/g, 51.16 ± 0.57 mg QE/g, and 2.40 ± 0.14 mg CE/g, respectively. On the other hand, the best radical scavenging activity (IC50 = 0.459 ± 0.022 mg/ml) and the highest reducing power activity (EC50 = 0.471 ± 0.022 mg/ml) were exhibited by the methanolic extract A. unedo. Whereas regarding the anti-inflammatory activities, A. unedo aqueous extract exerted the highest HRBC stabilization of 70.86 ± 0.61% and Egg albumin denaturation inhibition of 70.06 ± 0.68%. Overall, the results suggest that aqueous and methanolic extracts of A. unedo fruits can be used as future ethnomedicinal antioxidants and anti-inflammatories due to their rich content of bioactive molecules.