Improvement stability of phycocyanin from Spirulina platensis encapsulated by water soluble chitosan nanoparticles

Abstract

Spirulina platensis is a microalga containing protein and other nutrients, also pigments which has several advantages in food and pharmaceuticals. Phycocyanin is a blue pigment from Spirulina sp. composed by α and β polypeptide with phycocyanobilin. Phycocyanin can be extracted by ultra-sonication method. However, this pigment can be easily degraded because of its instability caused by pH, temperature, and light. One of methods for maintaining the stability is encapsulation by coating material. Water soluble chitosan (WSC) is known as a low-molecular weight and low toxic coating material dissolve in water. The purposes of this study were to determine phycocyanin extraction with different time and evaluate the stability of phycocyanin in WSC nanoparticles. Phycocyanin-WSC nanoparticles were prepared with three different ratio of WSC to phycocyanin i.e 1:1, 1:0.75, 1:0.5 (w/w). Extraction phycocyanin using ultrasonicator for 15 min showed the highest concentration (1.28 mg/mL) and yield (2.56%). The smallest size and narrow polydispersities of phycocyanin-WSC nanoparticles was achieved with ratio of WSC to phycocyanin of 1:0.75 (w/w). Encapsulation of phycocyanin in WSC nanoparticle enhanced the stability at 50°C for 90 min. Encapsulation can be used for any supplement application.