Valorization of rambutan (Nephelium lappaceum L.) peel: chemical composition, biological activity, and optimized recovery of anthocyanins

Chemical constituents and bioactive properties of rambutan (Nephelium lappaceum L.) peel were characterized and heat-/ultrasound-assisted extractions (HAE/UAE) of anthocyanins were optimized by response surface methodology. Five organic acids, the alpha-, gamma-, and delta-tocopherol isoforms, and twenty-five fatty acids (36.8 % oleic acid) were identified, as well as a phenolic profile composed of ellagitannin derivatives, geraniin isomers, ellagic acid, and delphinidin-O derivatives. The extract showed antioxidant activity via lipid peroxidation (IC50 = 2.79 +/- 0.03 mu g/mL) and oxidative hemolysis (IC50 = 72 +/- 2 mu g/mL) inhibition, and displayed antibacterial and antifungal properties (MIC <= 1 mg/mL). On the other hand, no cytotoxicity was observed in tumor and non -tumor cell lines up to 400 mu g/mL. The recovery of anthocyanins was more effective using HAE than UAE, allowing greater yields (16.2 mg/g extract) in just 3 min and using lower ethanol proportions. Overall, rambutan peel could be upcycled into bioactive ingredients and natural colorants for industrial applications.

URI

http://hdl.handle.net/10198/18538

Citation

Albuquerque, Bianca R.; Pinela, José; Dias, Maria Inês; Pereira, Carla; Petrović, Jovana; Soković, Marina; Calhelha, Ricardo C.; Oliveira, M. Beatriz P. P.; Ferreira, Isabel C.F.R.; Barros, Lillian (2023). Valorization of rambutan (Nephelium lappaceum L.) peel: chemical composition, biological activity, and optimized recovery of anthocyanins. Food Research International. eISSN 1873-7145. 165, p. 1-10