Microencapsulation of Curcuminoids by Spray Drying Techniques

Abstract

Curcuminoids were extracted from Curcuma Longa L. Its active constituents, curcumin, desmethoxycurcumin, and bisdesmethoxycurcumin, have been known to possess various pharmaceutical and cosmetic benefits, including anti-oxidation, inti-inflammation, anti-microbial, anti-cancer, etc. Curcuminoids are unstable when exposed to al-alkaline condition. In this study, the curcuminoids microcapsules were prepared by spray-drying technique in order to increase the stability of curcuminoids by employing of three different polymers; polymethacrylate (PM), polyvinyl acetate (PVA), and ethylcellulose(EC), and three different plasticizers; propylene glycol (PG), PEG-400, and glycerol triacetate (GTA) as the wall materials. The curcuminoid: polymer ratios were 1:1, 1:2, and 1:3 and percentage of solid content of the feed formulation were 1% and 2%. The spray-drying conditions were set as followed; inlet temperature of 120 °C, aspirator (air-flow volume) of 28 m³/h, and feed rate of 5 ml/min. The resulting curcuminoid microcapsules formulations with superior percent curcuminoids content and entrapment efficiency were selected. The selected formulations were PM-coated microcapsules plasticized with PG with percent curcuminoids content of 37.27% and percent entrapment of 74.54%, PM-coated microcapsules plasticized with PG/PEG400 with percent curcuminoids content of 27.30% and percent entrapment of 54.60%, EC-coated microcapsules plasticized with PG/GTA with percent curcuminoids content of 41.90% and percent entrapment of 83.80%, EC-coated microcapsules plasticized with PG with percent curcuminoids content of 53.60% and percent entrapment of 107.20%, and EC-coated microcapsules plasticized with PG/PEG400 with percent curcuminoids content of 48.11% and percent entrapment of 96.22%. Among these formulations of microencapsulated curcuminoids, PM-coated microcapsules plasticized with PG/PEG400 was found to be more stable and had remarkably higher percent retention of curcuminoids than other formulations. After the incorporation of selected microencapsulated curcuminoids and curcuminoid extract into cleansing gel pH 5 for 4 weeks, PM- and EC-coated microcapsules plasticized with PG were found to increase the curcuminoid stability in cleansing gel pH 5 and their percent retention of curcuminoids were markedly higher than those of other microcapsule formulations. However, it was not remarkedly different percent retention of curcuminoids from differently-coated microcapsules.