Preparation of arrowroot starch nanoparticles by butanol-complex precipitation, and its application as bioactive encapsulation matrix

Arrowroot starch is one of Indonesia’s local native starches derived from the Maranta arundinaceae tubers. This starch has high amylose content, increasing its potential to produce nano-sized V-amylose starch by butanol-complexed precipitation. One of starch pretreatments is lintnerization to produce crystalline and low DP starch. The aim of this research was to find out the characteristics of arrowroot starch nanoparticles produced by butanol-complex precipitation of lintnerized starch and its application as an encapsulation matrix for herb extract. Treatments involved lintnerized starch concentration of 5 and 10%, resulted from 2 and 24 hours of lintnerization process, and then each starch was precipitated by n-butanol. Preparation of starch nanoparticles by butanol precipitation following lintnerization of arrowroot starch produced nanosize particles ranged from 78.6 nm to more than 538.7 nm (average 261.4 nm), showing non-granular morphologies, and consisting of high porosities, as well as changing its crystalline pattern and thermal properties. The amylose content and solubility increased but enzymatic digestibility decreased to below than 60%. The lower particle size and enzymatic digestibility with high porosity made aroowroot starch nanoparticles suitable as controlled release matrix for bioactive compound. Application of starch nanoparticles as an encapsulation matrix for andrographolide extract showed smooth and sphere morphology with the average size about 200 nm. The FTIR spectra showed carbonyl strecthing band at 1727cm-1 from and rographolide.