Fuente: WIPO "tomato" The invention relates to recombinant host cells that expresses one or more genes encoding a cytochrome P450 enzyme capable of N-demethylating and/ O-demethylating reticuline and/or derivatives thereof, and also methods of producing a N-demethylated and/or O-demethylated reticuline and/or derivatives thereof, comprising cultivating the recombinant host of the invention in a culture medium under conditions in which the one or more genes encoding the cytochrome P450 enzymes is/are expressed. The reticuline and derivatives thereof are useful for providing access to naturally unavailable and chemically difficult-to-produce starting materials for opioids.