Microencapsulation of astaxanthin in alginate using modified emulsion technology: Preparation, characterization, and cytostatic activity

Abstract In the present study, astaxanthin was microencapsulated in a biodegradable material, calcium alginate, using a modified emulsion technology developed at our laboratory. The modified emulsion method involves the reaction between a sodium alginate emulsion and a calcium chloride emulsion. After mixing these emulsions, Ca 2+ penetrates two oil‐water layers to combine −COO ‐ , and microparticles are formed with narrow size distribution and good dispersion due to the mild reaction speed. The microencapsulated astaxanthin showed much higher storage stability and antioxidant activity than the non‐encapsulated astaxanthin. Cytostatic activity was preliminarily evaluated on adipose‐derived stem cells, the microencapsulated astaxanthin showed significant cytostatic activity due to the improved solubility of astaxanthin caused by the good biocompatibility of calcium alginate. Characterization confirmed the existence of microparticles with high encapsulation efficiency (more than 85 %), uniform size distribution (1.61 µm), and sustained astaxanthin release, suggesting the prepared microparticles by the modified emulsion method have great potential in pharmaceutical, food, and cosmetic industries.