oxidoreductase activity, acting on the CH-CH group of donors, quinone or related compound as acceptor 9,9'-di-cis-zeta-carotene desaturase activity https://github.com/geneontology/go-ontology/issues/25964 Catalysis of the reaction: 9,9'-di-cis-zeta-carotene + 2 a quinone = 7,7',9,9'-tetra-cis-lycopene + 2 a quinol. carotene 7,8-desaturase activity molecular_function carotene,hydrogen-donor:oxygen oxidoreductase activity zeta-carotene desaturase activity RHEA:30955 GO:0016719 MetaCyc:RXN-12242 EC:1.3.5.6