Abstract
The great interest in the potential health benefits of tropical fruits is due to their high content of antioxidants and phytochemicals. Colombia ranks as the second country with the major biodiversity worldwide. B. guineensis (Arecaceae) is a palm that grows in Colombia and Central America. The purple-black fruits of this plant are rich in thermal-stable anthocyanins. M. indica L. (Anacardiaceae) is a great source of phenolic compounds. It has multiple functional properties including antioxidant, antimicrobial, antidiabetic and anticarcinogenic activities. In this work, high-pressure extraction techniques: supercritical fluid extraction (SFE) and enhanced solvent extraction (ESE), and two different fractionation techniques: i) cascade fractionation and ii) sequential fractionation were applied. Fractions were analyzed by means of their phenolic content, antioxidant activity, and antibacterial activity against different bacterial strains: E. coli, P. mirabilis, S. Aurerus, S. enteritidis, E. aerogenes and P. aeruginosa. The sequential fractionation of B. guineensis pulp consisted in three steps: 1) supercritical CO2, 2) CO2 + 50% ethanol, and 3) CO2/EtOH/H2O (50:25:25). A red fraction rich in phenolic compounds, high antioxidant and antibacterial capacity (inhibition zone ~ 10 mm) was obtained in the last step. A cascade fractionation of M. indica leaves using CO2 + 50% H2O and three separators (S1, S2 and S3) was evaluated. Fractions obtained in S1 and S2 presented antioxidant capacity and antibacterial activity against P. mirabilis, and S2 also against S. Aureus and Salmonella.