Wild Andean blackberry (Rubus glaucus Benth) and Andean blueberry (Vaccinium floribundum Kunth) from the Highlands of Ecuador: Nutritional composition and protective effect on human dermal fibroblasts against cytotoxic oxidative damage

BACKGROUND: Andean blackberries (Rubus glaucus Benth) and Andean blueberries (Vaccinium floribundum Kunth) are wild berries consumed and commercialised by the indigenous people of the Andean regions of Ecuador. OBJECTIVE: This study aims to determine the chemical composition and the ability of A. blackberries and A. blueberries to protect human dermal fibroblast (HDFa) against cytotoxic oxidative damage. METHODS: Total phenolic, flavonoid, anthocyanins and tannins content were determined spectrophotometrically, while vitamin C and carotenes were determined by HPLC. Total antioxidant capacity was determined by the Ferric Reducing Antioxidant Power (FRAP) assay, the hydrogen peroxide scavenging activity and the DPPH and superoxide radical scavenging capacity. HDFa was pre-treated with A. blackberries or A. blueberries crude extract, subjected to a model of oxidative stress using the stressor 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and the markers of cell cytotoxic damage (intracellular ROS levels, catalase, superoxide dismutase and glutathione activities, lipid peroxidation, protein oxidation and ATP and nitrite levels) were determined. RESULTS: A. blueberries showed significantly high values of total phenolic, flavonoid, anthocyanin, lutein tannin content, whilst A. blackberries showed the highest values of vitamin C and beta-carotene. After HDFa was pre-incubated with crude extracts of A. blackberries and A. blueberries, the markers of oxidative damage were significantly improved compared with the stressed cells group. In all cases, crude extract of A. blueberries showed a higher protective effect compared to A. blackberries. CONCLUSION: A. blackberry and A. blueberry attenuated the oxidative damage in HDFa showing that both fruits may represent a relevant source of bioactive compounds with promising benefits for human health.