Nanoparticles based on biopolymers improved antioxidant activity of phenolic compounds from jambolan (Syzygium cumini (L.) skeels)

Abstract

Jambolan (Syzygium cumini L.) is an underutilized fruit rich in bioactive phenolic compounds, specially anthocyanins, but the low stability of these substances and interaction with other compounds in the food matrix limit their application as food additives; nanoencapsulation is the best strategy to overcome these limitations. This study aimed to nanoencapsulate a phenolic-rich jambolan extract using whey proteins and pectin by nanoprecipitation in different antisolvent compositions. Two formulations were synthesized (7.33 % extract, 1.67 % pectin, and 5 % concentrated or isolated whey protein) precipitated in different acetone concentrations (50, 70, and 100 % v/v). SEM showed particles with spherical shape and smooth surface. DLS pointed diameters between 82 nm and 116 nm. FTIR indicated chemical interactions between the materials. Encapsulation efficiency showed high phenolic compounds entrapment in all systems [73.81–84.65 %, p > 0.05]. However, particles precipitated in 50 and 100 % acetone (v/v) showed greater anthocyanins retention [56.89–35.24 %, p < 0.05]. Nanoencapsulation potentiated the antioxidant activity up to 110 % more than the crude extract (p < 0.05). These results show the potential of nanoprecipitation as an effective encapsulation process and the biopolymers combination to produce nanoparticles containing jambolan phenolic compounds to promote their application in foods and health products.

Keywords

• Anthocyanins
• Ultrasound assisted extraction
• High-Performance liquid chromatography
• Nanoprecipitation
• Whey protein. pectin