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31.
Evidence is presented indicating that intact plants of Hordeum vulgare degrade [α- 14C]hordenine to 14CO 2. 相似文献
32.
33.
《植物学报(英文版)》2005,47(7)
The Dai medicinal plant Winchia calophylla A. DC. (Apocynaceae) has efficacy as an anticough and anti-asthmatic medication. In order to investigate its relative bioactive components, we studied the chemical constituents of this plant. Using repeated column chromatography, 28 compounds, including loganin, six phenolic compounds, 17 indole alkaloids, three pyridine alkaloids, and a quinoline alkaloid,were isolated from the stem barks of W. calophylla. Loganin, paeonol, N (4)-methyl akuammicine, and cantleyine exhibited a moderate relaxation effect on isolated smooth muscles of guinea-pig tracheal spirals and lung strips and may be the bioactive components responsible for the bronchodilation produced by W. calophylla. 相似文献
34.
The 1H NMR spectra of three pyrrolizidine alkaloids of the macrocyclic diester type, retrorsine, seneciphylline and senecionine, plus their three N-oxides have been assigned. Previous 1H NMR studies of these pyrrolizidine alkaloids have stressed the difficulties of spectral intrepretation. The results reported here will provide a useful resource for analysis of tertiary structure in these and related compounds. 相似文献
35.
Ayaaki Ishizaki Hiroshiro Shibai Yoshio Hirose Teruo Shiro 《Bioscience, biotechnology, and biochemistry》2013,77(1):107-113
In inosine fermentation, the yield of the product was closely related to the partial pressure of carbon dioxide in the culture system rather than the bicarbonate ion concentration in the culture liquid. The inhibitory effect of carbon dioxide was restored by the methods of reducing the partial pressure of carbon dioxide lower than a certain level. Both ventilation and chemical absorption were applicable for the restoration of the carbon dioxide inhibition, but ventilation had great advantages over the other method from an industrial view-point. In the estimation of aeration-agitation conditions for the scale-up of submerged fermentation in which carbon dioxide was inhibitory, the rate of aeration was to be established to make sufficient ventilation and overcome this inhibition. A scheme for the procedure for the estimation of aeration-agitation conditions under the consideration of influences of carbon dioxide on submerged fermentation was proposed in this paper. 相似文献
36.
Quantification of Anti‐Addictive Alkaloids Ibogaine and Voacangine in In Vivo‐ and In Vitro‐Grown Plants of Two Mexican Tabernaemontana Species
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Felix Krengel Josefina Herrera Santoyo Teresa de Jesús Olivera Flores Víctor M. Chávez Ávila Francisco J. Pérez Flores Ricardo Reyes Chilpa 《化学与生物多样性》2016,13(12):1730-1737
Tabernaemontana alba and Tabernaemontana arborea are Apocynaceae species used in Mexican traditional medicine for which little phytochemical information exists. In this study, preliminary gas chromatography/mass spectrometry analyses of different organs obtained from wild plants of both species identified a total of 10 monoterpenoid indole alkaloids (MIAs) and one simple indole alkaloid, nine of which were reported for the first time in these species. Furthermore, callus cultures were established from T. alba leaf explants and regeneration of whole plants was accomplished via somatic embryogenesis. The anti‐addictive MIAs ibogaine and voacangine were then quantified by gas chromatography with flame ionization detection in wild plants of both species, as well as greenhouse‐grown plants, in vitro‐grown plantlets and embryogenic callus of T. alba. Ibogaine and voacangine were present in most samples taken from the whole plants of both species, with stem and root barks showing the highest concentrations. No alkaloids were detected in callus samples. It was concluded that T. alba and T. arborea are potentially viable sources of ibogaine and voacangine, and that these MIAs can be produced through somatic embryogenesis and whole plant regeneration of T. alba. Approaches to increase MIA yields in whole plants and to achieve alkaloid production directly in cell cultures are discussed. 相似文献
37.
Two new phenanthrene alkaloids, beilschglabrines A (1) and B (2) were isolated from the stem bark of Beilschmiedia glabra, together with lupeol, taraxerol, and 24-methylenelanosta-7,9-diene-3β-15α-diol. The structures of the isolated compounds were elucidated by extensive spectroscopic data analysis and comparison with respective literature data. The compounds were tested for DPPH radical scavenging, acetylcholinesterase and lipoxygenase inhibitory activities. Compound 1 displayed considerable activity in the acetylcholinesterase (IC50 50.4 μM), the DPPH radical scavenging (IC50 115.9 μM) and the lipoxygenase (IC50 32.8 μM) assays. 相似文献
38.
Several plant isoquinoline alkaloids (PIAs) possess powerful pharmaceutical and biotechnological properties. Thus, PIA metabolism and its fascinating molecules, including morphine, colchicine and galanthamine, have attracted the attention of both the industry and researchers involved in plant science, biochemistry, chemical bioengineering and medicine. Currently, access and availability of high‐value PIAs [commercialized (e.g. galanthamine) or not (e.g. narciclasine)] is limited by low concentration in nature, lack of cultivation or geographic access, seasonal production and risk of overharvesting wild plant species. Nevertheless, most commercial PIAs are still extracted from plant sources. Efforts to improve the production of PIA have largely been impaired by the lack of knowledge on PIA metabolism. With the development and integration of next‐generation sequencing technologies, high‐throughput proteomics and metabolomics analyses and bioinformatics, systems biology was used to unravel metabolic pathways allowing the use of metabolic engineering and synthetic biology approaches to increase production of valuable PIAs. Metabolic engineering provides opportunity to overcome issues related to restricted availability, diversification and productivity of plant alkaloids. Engineered plant, plant cells and microbial cell cultures can act as biofactories by offering their metabolic machinery for the purpose of optimizing the conditions and increasing the productivity of a specific alkaloid. In this article, is presented an update on the production of PIA in engineered plant, plant cell cultures and heterologous micro‐organisms. 相似文献
39.
Phytochemical investigation of the leaves and twigs of Tabernaemontana bovina led to the isolation of 10 monoterpenoid indole alkaloids, including two new taberbovinines A (1) and B (2) along with eight known analogs: mehranine (3), 14α,15β-dihydroxy-N-methylaspidospermidine (4), (16S*)− 15-epi-E-isositsirikine (5), (16R*)− 15-epi-E-isositsirikine (6), 16 R*-19,20-E-isositsirikine acetate (7), hecubine (8), voafinidine (9), and voacangarine (10). Taberbovinine B (2) represents the first case of an unusual ring C/D cleavage among the natural Corynanthe-type alkaloids. Compounds 2 and 8 exhibited weak cytotoxicity against five human cancer cell lines, including SK-LU-1, HepG2, MCF-7, SK-Mel-2, and LNCaP, with IC50 values ranging from 42.9 to 66.3 μM, whereas compounds 4 − 6 and 9 were cytotoxic toward MCF-7, SK-LU-1 and LNCaP cells, with IC50 values in a range of 51.6–93.3 μM. 相似文献
40.
Three undescribed aporphine alkaloids dasymaroine A (1), 3-methoxyoxoputerine N-oxide (2), and dasymaroine B (3), along with nine known analogues (4–12) were isolated from the stems of Dasymaschalon rostratum Merr. The structures were elucidated using spectroscopic methods and by comparison with published NMR spectroscopic data. Compound 1 is a rarely reported nitro aporphine alkaloid and its absolute configuration was defined based on negative specific rotation and single-crystal X-ray diffraction. Compound 2 represents the first example of oxoaporphine alkaloid N-oxide. All compounds were evaluated for their activities of six pathogenic bacteria, 1 exhibited significant inhibition against Escherichia coli and Saphylococcus aureus with MIC values of 1.2 and 2.5 μM, respectively. As well as compounds 1–5, 7, 10, 12 were evaluated for their anti-HIV activities with EC50 ranged from 1.93 to 9.70 μM. 相似文献