**2. Effect of** *Z***-isomerization of carotenoids on their bioavailabilities and functionalities**

The effects of *Z*-isomerization on the bioavailability and functionality of eight carotenoids have been investigated thus far, including: (1) the bioavailability and antioxidant activity of lycopene; (2) the antioxidant activity of α-carotene; (3) the bioavailability and antioxidant, antiatherogenenic, and antiatherosclerotic activities of β-carotene; (4) the bioavailability and antioxidant activity of astaxanthin; (5) the antioxidant and pro-apoptotic activities of canthaxanthin; (6) the antioxidant and anticancer activities of fucoxanthin; (7) the bioavailability and antioxidant activity of lutein; and (8) the antioxidant activity of zeaxanthin. The changes caused by *Z*-isomerization varied according to the parental carotenoid molecules tested and the evaluation method employed. The findings are described in detail below.
