An Assessment of Total Polyphenolic Content and Antioxidant Potential of Mauby Bark Extracts (Colubrina arborescens) Brewed for Different Lengths of Time

Mauby bark (Colubrina arborescens) is commonly used to make a beverage,“Mauby”, in the Caribbean and is believed to possess antiglycemic, antilipidemic, and anticarcinogenic properties. However, limited studies have been conducted to substantiate the compounds present that may confer these benefits. Therefore, the objectives of this research were to quantify the total polyphenolic content and evaluate the antioxidant capacity of Mauby bark extracts brewed in water at 30, 45, and 60 minutes. In the extracts, the Total Flavonoid Content (TFC) ranged from 1.93 - 3.17 mg CE/mL and the Total Phenolic Content (TPC) ranged from 2.10 mg ± 0.11 GAE/mL (45 minutes) - 2.36 mg ± 0.067 GAE/mL (30 minutes). Moreover, their antioxidant activity was assessed using the 2,2 Diphenyl 1-Picrylhydrazyl (DPPH) and  Ferric Reducing Antioxidant Power (FRAP) assays. The DPPH scavenging activity observed from Mauby extracts ranged from 75% ± 4.02 (30 minutes) to 83% ± 0.66 (60 minutes) and the FRAP values ranged from 6.29± 0.84 (30 minutes) to 6.90 ± 1.54 mM FeSO4 equivalents/ 0.2 mL Mauby extract (45 minutes). Although, polyphenolic content at 30 minutes was greater than 60 minutes of brewing for TFC (p < 0.001) and TPC (p = 0.002), the scavenging activity was greater at 60 minutes than 30 minutes (p = 0.014) while antioxidant power was not affected by brewing time (p = 0.736). In summary, brewing the bark at 60 minutes was observed to provide the highest antioxidant activity.