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

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.