Isomerization of β-carotene by titanium tetrachloride catalyst

IIsomerization of all-trans-β-carotene occurs during shaking with 0,5% of titanium tetrachloride catalyst in methylene chloride at room temperature. In the present study we compared two types of columns C18 and C30 and various solvent systems for the separation of β-carotene and its cis isomers by high performance liquid chromatography (HPLC). Results showed that β-carotene isomers were resolved by employing a C30 column with a mobile phase of methanol (100%) (A) and methylene chloride (100%) (B) under a gradient elution condition. A total of eleven cis isomers and one all-trans-β-carotene isomer were resolved within 50 min at a flow rate of 1 ml/min and detection wave-length of 470 nm.