β-胡萝卜素催化异构化及9-顺式β-胡萝卜素制备工艺研究

Catalytic Isomerization of β-Carotene and Preparation of 9-Cis β-Carotene

摘要:

β-胡萝卜素异构体中，9-顺式异构体具有更高的生理活性。通过碘掺杂二氧化钛纳米催化剂在乙酸乙酯中非均相催化全反式β-胡萝卜素异构化，制备高顺式构型占比的β-胡萝卜素。经液相－离子阱质谱联用仪分析，证实催化产物主要为15-顺式、13-顺式、9，13-双顺式、全反式和9-顺式等5种β-胡萝卜素异构体。以9-顺式β-胡萝卜素相对含量为评价指标，在单因素试验基础上，采用正交试验设计优选出制备高9-顺式β-胡萝卜素异构体的最优条件为：温度75 ℃，时间90 min，底物质量浓度1 mg/mL，催化剂添加量1.2 mg/mg（基于β-胡萝卜素），此时，9-顺式β-胡萝卜素异构体质量分数达到25.02%，总顺式异构体的质量分数为47.41 %。反应过程中β-胡萝卜素的降解率为12.6%。结论：碘掺杂二氧化钛纳米催化剂催化全反式β-胡萝卜素异构化适用于高9-顺式β-胡萝卜素的制备，此制备工艺简单且成本较低。

Abstract:

Among all β-carotene isomers，9-cis-β-carotene may be the most active one. The study first catalyzed the isomerization of β-carotene using the iodine doped Tio2 nano catalyst in an ethyl acetate system. HPLC-APCI-MS analysis showed the products contained 15-cis-，13-cis-，9，13-cis-，all-trans- and 9-cis-β-carotenes. On the basis of single factor and orthogonal experiments，the optimal parameters to produce 9-cis-β-carotene were determined to be reaction temperature 75 ℃，time 90 min，β-carotene concentration 1 mg/mL and catalyst dosage 1.2 mg/mg β-carotene，which resulted in a concentration of 25.02% for 9-cis-β-carotene and a concentration of 47.41% for all cis-isomers with a β-carotene degradation rate of 12.6%. Therefore，catalyzing the β-carotene isomerization with the iodine doped Tio2 nano catalyst was a simple and low cost method for the production of a high content of 9-cis-β-carotene.