Bioactive Compounds from Jambolan (Syzygium cumini (L.)) Extract Concentrated by Ultra- and Nanofiltration: a Potential Natural Antioxidant for Food.

Jambolan is an unexplored fruit rich in bioactive compounds like anthocyanins, catechin, and gallic acid. Thus, the extraction of bioactive compounds allows adding value to the fruit. In this context, the present study reports the recovery and concentration of jambolan fruit extract by ultra and nanofiltration for the first time. Acidified water was used to extract polyphenols from the pulp and peel of jambolan. The extracts were concentrated using ultrafiltration and nanofiltration membranes with nominal molecular weight cut-off ranging from 180 to 4000 g mol-1. Total monomeric anthocyanin, total phenolic compounds, and antioxidant capacity were analyzed. Phenolic compounds were quantified, and anthocyanins were identified by high-performance liquid chromatography coupled to diode-array detection and mass spectrometry (HPLC-DAD-MS). Concentration factors higher than 4.0 were obtained for anthocyanins, gallic acid, and catechin after nanofiltration of the extracts. Other compounds such as epicatechin, p-Coumaric acid, and ferulic acid were quantified in the concentrated extract, and the main anthocyanins identified were 3,5-diglucoside: petunidin, malvidin, and delphinidin. Therefore, jambolan extract showed a high potential to be used as a natural dye and antioxidant in food products.

Impact of the use of saccharides in the encapsulation of Ilex paraguariensis extract.

The yerba mate (Ilex paraguariensis A.St.-Hil.) is abundant on phenolic compounds and their preservation by encapsulation can promote increased stability. The objective was to produce mate extract with a high concentration of bioactive compounds, microencapsulate and characterize them. A commercial yerba mate was used to produce the extracts and select the best extraction solvent (ethanol, water, and ethanol:water (1:1). The ethanol:water extract was encapsulated at 1:1 (w/w) by fructooligosaccharide (FOS) and gum arabic (GA), in different combinations: FOS, GA:FOS (1:3), GA:FOS (1:1), GA:FOS (3:1) and GA. The encapsulation of chlorogenic acids was around 80%, considering the major phenolic compounds by HPLC. Thermal stability, by DSC, increased at treatments FOS, GA:FOS (1:3), and GA:FOS (1:1) compare to the unencapsulated extract, and changes were noticed in ATR-FTIR bands and antioxidant activity. The encapsulated phenolic compounds from I. paraguariensis can be stable in food under heat processing.