Extraction And Purification Of Capsaicinoids And Capsaicin

A process for extracting and purifying capsaicinoids and capsaicin from capsicum oleoresin was studied in this paper.The process includes extracting coarse capsaicinoids by solvent, purifying capsaicinoids by macroporous resin and crystalliz-ation,and preparating capsaicin by reversed-phase preparative liquid chromatog-raphy.In the experiments of extraction of coarse capsaicinoids by solvent, the optimal operation conditions were obtained by studying the effects of saponification and extraction on the purity and recovery. Firstly, capsicum oleoresin was saponified by a sodium hydroxide solution of 5% content, and the recovery was 98.74% while purity of capsaicinoids was improved from 34.89% to 65.20%. Secondly, the pH of saponified solution was conditioned to 9.57 and extracted with ether two times to increase the purity to 90.49% with a recovery of 98.75%. Thirdly, a 2% sodium hydroxide solution extracted the above ether raffinate three times and the purity was improved to 94.52 % with a recovery of 91.14%. Through the three processes, the capsaicinoids of 94.52% could prepared from capsicum oleoresin with the total recovery of 88.87%.In the experiments of purifying capsaicinoids, the methods of macroporous resin and crystallization were studied.In the method of macroporous resin,the effects of the concention,flow rate,pH value of capsaicinoids on the adsorption and the concention,flow rate on the desorption were studied.The optimal operations conditions were obtained:loading flow rate:1.91BV/h;loading sample pH:12.3 0; eluant:firstly 20% acidic ethanol solution, then 70% ethanol solution;eluating flow rate: 1.35BV/h .The purity and the recovery of product were 99.91% and 69. 41% respectively. In the method of crystallization, pH 12.02～12.21and 10℃ were the optimal conditions.The purity of the product was 98.73% with the recovery 88.77 % .Through these experiments,high purity product can be obtained by the two methods. The purity of the product prepareded by the mothod of macroporous resin islitterly higher than the product by crystallization,but the recovery is lower.The method of crystallization can be operated more simply .In the experiments of capsaicin by reversed-phase preparative liquid chromatog-raphy, the effects of mobile phase composition and flow rate, feed concentration and volume on the purity, productivity, recovery and mobile phase consumption were studied. With two ODS column(l00mm×20mm id), the optimal operation conditions are mobile phase with methanol/water(75/25,V/V), sample concentration with 180mg/ml, sample volume with 2.08ml and flow rate with 4ml/min.Under such conditions, capsaicin with purity of 95.23% could be obtained, and the productivity, recovery and mobile phase consumption were 4.38g/L, 93.27% and 0.087L/g, respectively. The result shows that the method proposed is simple and high efficient. It was provided a new method for the preparative of capsaicin.In this paper,the analytical method for capsaicinoids and capsaicin was HPLC.