The secondary metabolites of higher plants include diverse chemicals, such as alkaloids, isoprenoids and phenolic compounds (phenylpropanoids and flavonoids). Although these compounds are widely used in human health and nutrition, at present they are mainly obtained by extraction from plants and extraction yields are low because most of these metabolites accumulate at low levels in plant cells....

Isoquinoline alkaloids are a major group of pharmacologically important compounds. The universal precursor to the majority of this alkaloid class is (S)-reticuline. The biosynthesis of this important intermediate starting from the primary metabolite, Ltyrosine, has been completely solved at the enzyme level. One of the most diverse structures in the class of isoquinoline alkaloids are the benzo...

Opium poppy (Papaver somniferum) produces a diverse array of bioactive benzylisoquinoline alkaloids, including the narcotic analgesic morphine and the antimicrobial agent sanguinarine. In contrast to the plant, cell cultures of opium poppy do not accumulate alkaloids constitutively but produce sanguinarine in response to treatment with certain fungal-derived elicitors. The induction of sanguina...

Morphine biosynthesis was genetically engineered in an industrial elite line of the opium poppy (Papaver somniferum L.), to modify the production of alkaloids in plants. The cytochrome P-450-dependent monooxygenase (S)-N-methylcoclaurine 3'-hydroxylase (CYP80B3) lies on the pathway to the benzylisoquinoline alkaloid branch point intermediate (S)-reticuline. Overexpression of cyp80b3 cDNA result...

A quantitative analytical method for five aporphine alkaloids, nuciferine (1), nornuciferine (2), N-methylasimilobine (3), asimilobine (4), and pronuciferine (5), and five benzylisoquinoline alkaloids, armepavine (6), norarmepavine (7), N-methylcoclaurine (8), coclaurine (9), and norjuziphine (10), identified as the constituents responsible for the melanogenesis inhibitory activity of the extra...

Six new bisbenzylisoquinoline alkaloids (1-6) and seven known compounds (8-14) were isolated from the tubers of Stephania epigaea, in addition to the major alkaloid, cepharanthine (7). The structures of 1-6 were elucidated by combined spectroscopic data analysis and chemical methods, with their configurations determined from their optical rotation values and confirmed using circular dichroism. ...

The incorporation rates of labelled tyrosine, D O P A , tyramine, and dopamine have been inves­ tigated during the in vivo formation of the protoberberine alkaloid, jatrorrhizine, in callus cul­ tures o f Berberis canadensis. W hile tyrosine was equally well incorporated into both the isoquinoline (54% ) and benzyl (46% ) portions o f the alkaloid. D O PA was almost exclusively (91%) transforme...

Two aphorpine alkaloids, (+)-lirinine 1 and (+)-lirioferine 2 and two bezylisoquinoline alkaloids (+)reticuline 3 and (-)-N-Methylisococlaurine 4 were isolated from bark of Cryptocarya crassinervia. The structures were elucidated by spectral analysis, including 1D-NMR (H, C, DEPT), 2D-NMR (COSY, HMQC, HMBC), UV, IR, and MS and comparison with the published data.