Spray-dried polymeric microparticles fabrication for improvement of Homnil rice extract stability

Abstract

Background and objectives: Homnil rice is a hybrid rice between Khao-Khaow-Dokmali 105 and Chinese black glutinous rice. It is a pigmented rice which is the rich source of anthocyanins that provides more health benefits than white rice. This research aimed to fabricate polymeric microparticles loaded Homnil rice extract to improve the stability of anthocyanins. Findings: Homnil rice was extracted with various solvents and determined for antioxidant activity. The best extract was selected to develop into polymeric microparticles using spray-drying method. The 50% ethanolic extract (50SE) showed the highest antioxidant activity which is related to its high total anthocyanin content. The best polymeric microparticles consisted of 0.05% w/w xanthan gum, 0.2% w/w carboxymethyl cellulose, and 0.3% w/w hydroxyethyl cellulose. Homnil rice extract-loaded polymeric microparticles (HELPM) showed a spherical morphology with porous surface measured by SEM and presented a high entrapment efficiency. It could partially protect the degradation of anthocyanins. The antioxidant activity and total anthocyanin content of HELPM were significantly improved when compared with crude extract after stability study. Conclusions: Our study provided alternative formulation for enhancing the stability of anthocyanins in Homnil rice extract. Significance and novelty: The HELPM was a promising edible and inexpensive active ingredient which is easily prepared by spray-drying technique that can be commercially scale-up. In addition, the HELPM powder possessed a potential to prevent the degradation of anthocyanins that could be further used in as an active ingredient in functional food, nutraceutical, and cosmeceutical industries.