Kinetics modelling of bioactive compounds extraction from rambutan (Nephelium lappaceum l.) by-products and their antioxidant activities

Abstract

Rambutan (Nephelium lappaceum) and its by-products have great potential in the agricultural, pharmaceutical, and food industries due to its antimicrobial, antioxidant, anti-diabetic, and anticancer properties. This study aimed to obtain rambutan extract rich in phenolic compounds with possible antioxidant properties by using extraction parameters such as temperature, solvent, and liquid to solid ratio. Once total phenolic compounds (TPC) from rambutan peel and seed were extracted, antioxidant assays such as 2, 2-diphenyl-1-picrylhydrazyl (DPPH•), 2, 2ˊ-azinobis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS•), and ferric reducing antioxidant power (FRAP) were investigated and optimization was performed by means of Second-order, Power, Peleg and Page’s law models. The results show that rambutan extract possesses scavenging effects on DPPH• radical and ABTS• radical cation, as well as FRAP capacity. The antioxidant profile and phenolic content of rambutan extract was noted to be altered by temperature and extraction time with the highest extraction efficiency achieved after 120 min at 45 °C. Furthermore, Peleg model with R2 > 0.89 was found to be the best model to describe the generated extraction data. The outcome of this study showed that the solid-liquid extraction could be an efficient extraction technique to obtain rambutan extract rich in phenolic compounds with high antioxidant properties.