SUMMARY The distribution of berberine and sanguinarine was analyzed in roots, stems and leaves of mature Argemone mexicana plants, along with that of transcripts corresponding to selected genes involved in both early biosynthetic reactions, which are common to both alkaloids, and in the late specific reactions conducting to the formation of each of them. Roots were the main sites of alkaloid accumulation, though they showed the lowest accumulation of the analyzed transcripts. Results are discussed in terms of the operation of a possible transport mechanism of alkaloids between the aerial tissues and the roots, or the occurrence of different biosynthetic alternative reactions in both parts, aerial and underground tissues, involving different gene products, yet with similar catalytic capacities.

RESUMEN La distribución de berberina y sanguinarina se analizó en raíces, tallos y hojas de plantas adultas de Argemone mexicana, junto con la de los transcritos correspondientes a genes seleccionados involucrados tanto en las reacciones biosintéticas iniciales, que son comunes para ambos alcaloides, como en las reacciones específicas finales que conducen a la formación de cada uno de ellos. Las raíces fueron los sitios de mayor acumulación de alcaloides a pesar de que mostraron la menor acumulación de los transcritos analizados. Estos resultados se discuten en función de la operación de un posible mecanismo de transporte de alcaloides entre los tejidos aéreos y las raíces o bien, de la ocurrencia de alternativas biosintéticas diferentes en tejidos de ambas partes, aéreos y subterráneos, con productos génicos diferentes, pero con similares capacidades catalíticas.

A sensitive, simple, rapid and reliable HPLC-DAD method for the analysis of the benzylisoquinoline alkaloids (BIA's) content in Argemone mexicana (Papaveraceae) is presented. This method allows the simultaneous separation and quantitation of berberine (Bn), chelerythrine (C) and sanguinarine (S) in extracts from A. mexicana tissues, reducing time of analysis in comparison to previous reports. Alkaloids were separated on a C18 Hypersil Gold column using an acetonitrile gradient (20 to 70%) in 1% acetic acid in water. Alkaloids were identified based on retention times and UV spectra and quantified at 254 nm. Linearity between 0.5-20 µg mL-1 was observed for Bn, C and S, with limits of detection (LOD) and quantitation (LOQ) of 0.11 and 0.33 for Bn, 0.10 and 0.30 for C and 0.05 and 0.15 for S, respectively. Maximal intra- and inter-day variation values were < 0.49% in all cases, with alkaloids' recoveries higher than 95%. System suitability tests (SST), including resolution (Rs), retention factor (K'), selectivity (α), tailing factor and number of theoretical plates were performed according to the United States Pharmacopeia (USP), fulfilling recommended values. The method proved to be efficient and reproducible when analyzing different tissues of field-collected A. mexicana plants.

Cyclolignan (+)-lyoniresinol (1), veratric acid (2), vanillic acid (3), lupeol, oleanolic acid, 3β-hydroxy-urs-11-en-28,13β-lactone (4), the mixture of α- and β-amyrin, trans-polyisoprene, and β-sitosterol were isolated from the leaves of Maytenus phyllanthoides. The structures of the isolated compounds were established based on spectroscopic data, mainly ¹H and 13C nuclear magnetic resonance (NMR). Compound 1, its acetate analog 1a, and compounds 2, 3, and 4 were tested against Trichomonas vaginalis. (+)-Lyoniresinol showed activity corresponding to IC50 17.57 µM. This is the first report on the occurrence of 3β-hydroxy-urs-11-en-28,13β-lactone (4) in the Celastraceous family and lyoniresinol in the Maytenus genus, and on the antitrichomonal activity of lyoniresinol.