Mikroenkapsulasi Ekstrak Rimpang Temulawak (Curcuma xanthorriza. Roxb) Tersalut Gel Kitosan-Alginat

Abstract

Microencapsulation was done using the temulawak extract with curcumin as a target material. The aims of this research were to study (1) the transport properties of curcumin passing through the chitosan-alginate membranes due to diffusion process, (2) the optimum condition of in vitro dissolution behavior, and (3) the effects of oxidation and hydrolysis to storage conditions of curcumin coated chitosan-alginate gel. The maceration process using ethanol yields 17.08% and the content of the curcumin in the extract detected by visible spectrophotometry λ 430 nm was 10.30%. Chitosan-alginate membranes were prepared by mixing 100 ml chitosan 2.50% (b/v); 16.7 ml alginate 0.62% (b/v); and 1.70 ml glutaraldehide 4.63% (v/v) solutions, were poured into mould. Membranes thickness was varied by changing chitosan solution volume. Then, the membranes were used in diffusion assay at 37 and 40oC. Two degrees of donor concentration (Cd) was used 4 and 8 g/l, whereas recipient compartment was filled with solvent. Aliquots were taken after 30, 60, 90, 120, 150, and 180 minutes. The Aliquots absorbance was measured at λ 430 nm. Based on linear regression method, it was found that the influence of T, Cd, and h on D, J (Fick), and D, Jo (Higuchi), were not significant. On the other hand, the influence of T, Cd, and h on D, J (Fick), and D, Jo (Higuchi) using response surface method yield model equations with R2 98.6% and 99.4%. Matrix formation of curcumin for sustained released which is coated by chitosan-alginate gel ware made in a form of a microencapsulation using spray dryer technique. Its optimum condition was obtained using response surface method at concentrations ratio of alginate 0.62% (b/v) and glutaraldehide 4.63% (v/v) respectively, while chitosan concentration was fixed (1.75% [b/v]). The dissolution assay was done at 37oC, at 100 rpm of stirring rate in 8 hours. Aliquots were taken at 15, 30, 45, 60, 90, 120, 150, 180, 240, 300, 360, 420, 480 minutes. Absorbance of the Aliquots was measured at λ 430 nm. The curcumin released has the best linear correlation to the first order reaction with released constant, k = 2.25.10-3 minute-1 while it’s half live is t1/2= 5.16 hours. Release curcumin was determined mainly by diffusion mechanism. The Higuchi model was better than Fick model for determined the dissolution process. The storage assay for the microencapsulation process of temulawak ethanol extract showed that the room temperature was the best condition for maintaining the curcumin release. In this case, the data was suitable with the third order reaction with released constant, k = 0.6193 10-3 week-1 while it’s half life was t1/2 = 29.90 week.