RESUMO
Structure-based molecular networking is useful as a dereplication strategy to identify known molecules, unknown close analogues, or compound families. On the other hand, the ligand fishing assay is a remarkable alternative to accelerate the screening process and to overcome the drawbacks of laborious experiments usually adopted in natural product research. The combination of these approaches contributes to high productivity in disclosing active metabolites and a decrease in lead time identification. To provide a valuable data base for the alkaloids of A. salzmannii bark herein we disclose thirty-one isoquinoline alkaloids including benzyltetrahydroisoquinolines, aporphines, proaporphines, and protoberberines. Among these, twenty-six have not been described for A. salzmannii including the unprecedented alkaloid N,O-dimethylcoclaurine N-oxide. In addition, norcoclaurine (1), norreticuline (13), N,O-dimethylcoclaurine N-oxide (15), and N-acetylasimilobine (24) are now reported for the first time as ligand for acetylcholinesterase.
Assuntos
Acetilcolinesterase/metabolismo , Alcaloides/análise , Annona/química , Cromatografia de Afinidade/métodos , Extratos Vegetais/química , Alcaloides/química , Alcaloides/metabolismo , Enzimas Imobilizadas/metabolismo , Isoquinolinas/análise , Isoquinolinas/química , Isoquinolinas/metabolismo , Espectrometria de Massas/métodos , Casca de Planta/químicaRESUMO
Annona crassiflora Mart. is a native tree from Brazilian savanna. Isoquinoline alkaloids are characteristic of species of Annonaceae. This work aimed to assess the magnitude of genetic diversity among different populations of A. crassiflora using AFLP markers, and verify the existence of any correlation between the AFLP data and previous reported alkaloid composition. A. crassiflora from eight populations in the states of São Paulo, Goiás, Minas Gerais, and Distrito Federal were analyzed. The data suggest a low, moderate, and high level of genetic diversity from different populations of A. crassiflora. Concentration of alkaloids was significantly correlated with AFLP data, suggesting interaction between chemical and molecular markers in A. crassiflora. The data of association between the chemical and genetic differentiation of A. crassiflora may be useful to establish cultivation areas allowing the definition of strategies to preserve their genetic diversity with an interest in specific chemotypes for genetic improvement programs focused on sustainable utilization of this specie.
Assuntos
Annona/química , Annona/genética , Isoquinolinas/análise , BrasilRESUMO
A protocol for the induction of a cell suspension culture of Argemone mexicana is described. This suspension has been kept for over 3 years producing sanguinarine, a benzophenanthridine-type alkaloid. Sanguinarine levels can be increased by exposing these cultures to yeast or fungal elicitation.
Assuntos
Argemone/citologia , Benzofenantridinas/análise , Técnicas de Cultura de Células , Isoquinolinas/análise , Células Vegetais/química , Suspensões/química , Argemone/químicaRESUMO
Four quaternary isoquinoline alkaloids, dehydrocorydalmine, jatrorrhizine, columbamine, and oxyberberine, have been isolated from the whole plant of Argemone mexicana Linn. (Papaveraceae) and their structures established by spectral evidence. This is the first report of these alkaloids (dehydrocorydalmine, jatrorrhizine, columbamine, and oxyberberine) from Argemone mexicana and the Argemone genus.
Assuntos
Alcaloides , Argemone/química , Isoquinolinas , Alcaloides/análise , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides de Berberina/análise , Alcaloides de Berberina/química , Alcaloides de Berberina/isolamento & purificação , Isoquinolinas/análise , Isoquinolinas/química , Isoquinolinas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Espectrofotometria Ultravioleta , Temperatura de TransiçãoRESUMO
Astrocytes were cultured from striatum and neocortex of fetal (embryonic day 90) monkeys (Cebus apella). The cultures grew well, and the cells retained viability after freeze-storage and thawing. The cells displayed depolarized membrane potentials (-19 and -33 mV, for striatal and cortical cells, respectively) and the vast majority of cells were dye-coupled to a mean of 7 (1-18) neighbouring cells. Cell coupling was blocked by octanol (0.25 and 0.5 mM) but was independent of high K+ (10 and 50 mM) and glutamate (500 microm). Thus, cultures of fetal primate astrocytic cells are established as a model system for studies on astroglial cell-cell coupling.