| Summary: | 碩士 === 國立中興大學 === 化學工程學系所 === 102 === Curcumin is a major bioactive constituent of turmeric rhizome root, which is widely used in Chinese herbal medicine. It possesses anti-inflammatory, anti-oxidative and anti-tumor activity. Recent studies found curcumin is good at degrading alcohol. In this study, supercritical anti-solvent (SAS) crystallization of curcumin was carried out at 373K, 12 MPa, 15L/min of CO2 flow rate to produce nano-sized particulates with high dissolution rate in an aqueous solution. Feed concentration ranged from 5mg/mL to 10mg/mL, feed flow rate ranged from 0.3ml/min to 0.5ml/min, and feed solution of acetone or ethyl acetate were examined in the SAS crystallization process. A simulated intestinal solution at pH7.4 and a citrate-sodium di-hydrogen phosphate buffer at pH4.0 were used in dissolution rate tests of the SAS precipitates in aqueous solution adding with twenty comprising polysorbate 20 (Tween 20) or polysorbate 80 (Tween 80), respectively. Our experimental results showed that the SAS precipitates from the CO2 + ethyl acetate (SAS-C-EA) present high dissolution rate than those of raw curcumin (Raw-C) and the SAS precipitates from CO2 + acetone (SAS-C-A). The
dissolution rate of the SAS-C-EA precipitates in the intestinal fluid added with 5mg/mL Tween 20 attained 96% in a period of 10 minutes, while in the citrate-sodium di-hydrogen phosphate fluid added with 5mg/mL Tween 20, it
reached 93% within 10 minutes. A micro-sized co-precipitate of curcumin with sucrose ester (SAS-C-EA+SE) was also generated at the same operation condition of the SAS crystallization process. Dissolution rates of the co-precipitate in the intestinal and citrate-sodium di-hydrogen phosphate fluids added with 5mg/mL Tween 20 achieved 95% and 97%, respectively in a period of 10 minutes. Comparison among dissolution rates of those SAS precipitates and raw-curcumin indicated that the SAS precipitates from the CO2+ethyl acetate solution and the co-precipitate of curcumin with sucrose eater display a suitable solubility in the aqueous solutions added with the Tween 20 emulsifier.
This work demonstrated that supercritical anti-solvent crystallization of curcumin is a green process to produce nano-sized particulates and/or co-precipitate with sucrose ester having a fast dissolution rate in an aqueous
solution.
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