Research Topic: Developing starch nanoparticles from waxy rice starch by advanced green chemistry techniques for bioactive compound encapsulation
Abstract: ** Lecture will be given in English**
Starch nanoparticles (SNP) can be used as biodegradable materials for the encapsulation and delivery of bioactive compounds. However, their sustainable production remains a significant challenge, as traditional methods are hindered by low yields, poor scalability, and use of high concentrations of acid. In this study, an enzymatic method was developed to produce SNP from waxy rice starch, offering high efficiency and potential for large-scale production, suitable for encapsulation and protection of bioactive compounds.
The research includes a detailed characterization waxy rice starch from eight Japonica waxy rice cultivars, linking amylopectin fine structure to functional properties. Using this insight, starch from three cultivars with different structures were selectively modified with α-amylases from different sources (porcine pancreas, Bacillus amyloliquefaciens, and Aspergillus oryzae), demonstrating how α-amylase from various sources differ in their action on waxy rice starch with different structures.
An efficient SNP synthesis method was established using α-amylase pretreatment, pullulanase debranching, and nanoprecipitation, producing compact SNP as revealed by Cryo-EM. To overcome the hydrophobicity limitation for encapsulating hydrophobic compounds, SNP were modified with citric acid and successfully loaded with hesperetin, a hydrophobic flavonoid. In vitro digestion showed that this encapsulation significantly increased the retention of antioxidant and anti-diabetic activity of hesperetin. Finally, hesperetin-loaded SNP were incorporated into starch-based edible films, which extended blueberry shelf-life by increasing the barrier properties of starch-based films.
Overall, by integrating insights on waxy rice starch amylopectin structure, source-specific enzyme selection, and hydrophobic modification, this work offers a route to produce new bioactive-loaded SNP, with potential for further applications.
