In?Rubrivivax gelatinosus?[1] and?Thiocapsa roseopersicina?[2] both products are formed, whereas?Rhodobacter capsulatus?[1] only gives 1-hydroxy-1,2-dihydrolycopene. Also acts on neurosporene giving 1-hydroxy-1,2-dihydroneurosporene with both organisms but 1,1′-dihydroxy-1,1′,2,2′-tetrahydroneurosporene only with?Rubrivivax gelatinosus.