Enzyme-Assisted Extraction of Anthocyanin from Kokum (Garcinia indica Choisy) Rinds

Abstract

Background: The kokum rind consists of high amount of anthocyanin. The traditional methods are not capable to extract anthocyanin completely. Aims: The present study was focused on the optimization of enzyme pretreatment for extraction of anthocyanin from Kokum rind. Methodology: A central composite design was used to optimize the enzyme-assisted extraction of anthocyanin from the Kokum rinds. Kokum rinds was pretreated with food-grade pectinase and cellulase enzymes separately and then subjected to acidified ethanol extraction. The factors investigated included enzyme concentration (0 – 2%), Incubation time (1-5 h) and pretreatment temperature (15–55ºC). Results: Overall, 107.17- to 63.71 - fold increase in anthocyanin recovery when treated with pectinase and cellulase, respectively was observed compared to the untreated rinds. From a response surface analysis of the data, a second-degree polynomial equation was developed which provided the following optimal extraction conditions i.e. enzyme concentration 0.5%, Incubation time 2.0h and temperature 35ºC for pectinase pretreatment. Whereas, in case of cellulase the optimum conditions was enzyme concentration 1.42%, Incubation time 4.0h and temperature 32ºC. The obtained results strongly support the idea of using cell-wall degrading enzymes as an effective means for recovering anthocyanin from Kokum rinds.