September 09, 2025 | International Journal of Molecular Sciences |
The study conducted by Universidad San Francisco de Quito (USFQ) and Universidad Politécnica Salesiana, Ecuador, examined the potential of rambutan (Nephelium lappaceum) shell as a source of valuable bioactive compounds. Rambutan shell is an abundant agro-industrial by-product rich in phenolic acids and minor anthocyanins, but its direct application is limited due to instability and low bioavailability.
To address this, the researchers extracted phenolic-rich fractions and produced maltodextrin-based microcapsules using spray drying. FTIR, SEM, and XRD analyses confirmed successful encapsulation and the amorphous nature of the microcapsules. The encapsulated material showed high encapsulation efficiency and strong antioxidant activity. The microcapsules also demonstrated selective antibacterial effects, showing bactericidal activity against Pseudomonas aeruginosa and Burkholderia cepacia and inhibiting biofilm formation by Staphylococcus aureus and Listeria monocytogenes. Hemolysis tests indicated good biocompatibility, with less than 2% hemolysis across tested concentrations.
Moderate antitumor effects were observed, though with low selectivity, suggesting that further refinement of phenolic fractions or delivery strategies may be needed for therapeutic applications. Overall, the study highlights the potential of spray-dried rambutan shell microcapsules as stable, safe, and multifunctional ingredients for food and biomedical uses, while supporting the sustainable valorization of agricultural waste.
