Bioconversion of lutein to form aroma compounds by Pantoea dispersa

To investigate the conversion of lutein, a carotenoid, to aroma compounds by Pantoea dispersa Y08, a lutein-degrading bacterium isolated from marigold flower residue. Bioconversion conditions, including substrate concentration, applied co-solvent and reaction time, were optimized.

A maximum biodegradation yield of 80 % for lutein at 10 g/l was achieved. The intermediate, 3-hydroxy-β-ionone, and final β-ionone products were revealed by GC-MS. A bioconversion pathway of lutein is proposed to involve cleavage at the 9-10 double bond position, followed by de-hydroxylation at the 3-hydroxy position.

This is the first report of the ability of a bacterium, P. dispersa, to sequentially convert lutein to 3-hydroxy-β-ionone and then β-ionone.