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Crocins are important natural products predominantly obtained from the stigma of saffron, and that can be utilized as a medicinal compound, spice, and colorant with significant promise in the pharmaceutical, food, and cosmetic industries. Carotenoid cleavage dioxygenase 2 (<i>Cs</i>CCD2) is a crucial limiting enzyme that has been reported to be responsible for the cleavage of zeaxanthin in the crocin biosynthetic pathway. However, the catalytic activity of <i>Cs</i>CCD2 on β-carotene/lycopene remains elusive, and the soluble expression of <i>Cs</i>CCD2 remains a big challenge. In this study, we reported the functional characteristics of <i>Cs</i>CCD2, that can catalyze not only zeaxanthin cleavage but also β-carotene and lycopene cleavage. The molecular basis of the divergent functionality of <i>Cs</i>CCD2 was elucidated using bioinformatic analysis and truncation studies. The protein expression optimization results demonstrated that the use of a maltose-binding protein (MBP) tag and the optimization of the induction conditions resulted in the production of more soluble protein. Correspondingly, the catalytic efficiency of soluble <i>Cs</i>CCD2 was higher than that of the insoluble one, and the results further validated its functional verification. This study not only broadened the substrate profile of <i>Cs</i>CCD2, but also achieved the soluble expression of <i>Cs</i>CCD2. It provides a firm platform for <i>Cs</i>CCD2 crystal structure resolution and facilitates the synthesis of crocetin and crocins.