Variation in phenolic compounds of Ugni molinae populations and their potential use as antioxidant supplement

In the present work we carried out a comparative study of total phenolic contents and antioxidant capacity of aqueous leaf extracts of Ugni molinae Turcz., Myrtaceae (infusion and Soxhlet extracted) prepared from continent and Juan Fernandez Island samples. The results revealed that total phenol content (TPC), tannins (TTC) and flavonoids (TFC) for U. molinae extracts (infusion and Soxhlet extracts) from island leaves were 38.5, 56.7 and 37.5% higher than those obtained with leaves from the continent, respectively. Also, HPLC profiles showed important differences between U. molinae populations. In vitro antioxidant capacity (scavenging of DPPH radical) for 1% infusion and aqueous extract (Soxhlet method) of U. molinae from island samples, was 15% greater than from continent samples. Further, in vivo impact of U. molinae intake (1% infusion) was studied in plasma samples obtained from healthy volunteers. Participants that consumed tea prepared with leaves from island population showed higher TBARS reduction and plasma antioxidant capacity (TEAC-CUPRAC) than those who consumed tea prepared with leaves from continental population. The conditions of the territory in which U. molinae populations growth could explain the differences in their composition and activity. According to results, island U. molinae populations could be an important source of study for the development of an antioxidant supplement, and thereby contribute to the use of this species that has becoming an ecological problem in the island.