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71.
Binding affinity and in vitro cytotoxicity of harmaline targeting different motifs of nucleic acids: An ultimate drug designing approach
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Paromita Bhattacharjee Tapas Ghosh Sarita Sarkar Prateek Pandya Kakali Bhadra 《Journal of molecular recognition : JMR》2018,31(4)
The work focuses towards interaction of harmaline, with nucleic acids of different motifs by multispectroscopic and calorimetric techniques. Findings of this study suggest that binding constant varied in the order single‐stranded (ss) poly(A) > double‐stranded calf thymus (CT) DNA > double‐stranded poly(G)·poly(C) > clover leaf tRNAPhe. Prominent structural changes of ss poly(A), CT DNA, and poly(G)· poly(C) with concomitant induction of optical activity in the bound achiral alkaloid molecule was observed, while with tRNAPhe, very weak induced circular dichroism perturbation was seen. The interaction was predominantly exothermic, enthalpy driven, and entropy favored with CT DNA and poly(G)·poly(C), while it was entropy driven with poly(A) and tRNAPhe. Intercalated state of harmaline inside poly(A), CT DNA, and poly(G)·poly(C) was shown by viscometry, ferrocyanide quenching, and molecular docking. All these findings unequivocally pointed out preference of harmaline towards ss poly(A) inducing self‐structure formation. Furthermore, harmaline administration caused a significant decrease in proliferation of HeLa and HepG2 cells with GI50 of 28μM and 11.2μM, respectively. Nucleic acid fragmentation, cellular ultramorphological changes, decreased mitochondrial membrane potential, upregulation of p53 and caspase 3, generation of reactive oxygen species, and a significant increase in the G2/M population made HepG2 more prone to apoptosis than are HeLa cells. 相似文献
72.
A. Giri S. Banerjee P. S. Ahuja C. C. Giri 《In vitro cellular & developmental biology. Plant》1997,33(4):280-284
Summary A method for the production of hairy roots of Aconitum heterophyllum wall. is reported for the first time. Embryogenic callus cultures were successfully transformed using Agrobacterium rhizogenes strains viz. LBA 9402, LBA 9360, and A4 for the induction of hairy roots. The transgenic nature of hairy roots was confirmed
by mannopine assay using paper electrophoresis. Best growth of transformed roots was obtained on 1/4 MS (Murashige and Skoog,
1962) medium with 3% sucrose. Total alkaloid (aconites) content of transformed roots was 2.96%, which was 3.75 times higher
compared to 0.79% in the nontransformed (control) roots. Thin layer chromatography (TLC) analysis of the components of aconites
in the transformed roots revealed the presence of heteratisine, atisine, and hetidine. 相似文献
73.
A new alkaloid, scholaricine, has been isolated to which structure 2 (demethylscholarine) has been assigned. 相似文献
74.
Ammodendrine, together with seven other known lupin alkaloids, was isolated from Thermopsis lupinoides. (+)-Lupanine (+)-17-oxolupanine occurred together with (?)anagyrine, (?)-baptifoline, (?)-cytisine, (?)-N-methylcytisine (?)N-formylcytisine. These alkaloids have the opposite stereochemistry to that of (+)-lupanine and (+)-17-oxolupanine. The distribution of alkaloids in fresh flowers, leaves, stems roots of this plant was also examined. 相似文献
75.
76.
Five compounds were isolated from Buxus microphylla Sieb. et Zucc. Based on the physico-chemical constants and spectral analysis (IR, MS, 1H-NMR and 13C-NMR), they were identified as cycloprotobuxinamine ( Ⅰ ), buxmicrophylline A ( Ⅱ ), buxtauine M ( Ⅲ ), isoscopoletin (Ⅳ) and epi-lupeol ( Ⅴ ). ( Ⅰ ) and ( Ⅱ ) were new compounds. The structure of buxmicrophylline ( Ⅱ ) was confirmed by X-ray crystallographic analysis. 相似文献
77.
Ryo Nakabayashi Noriko Takeda-Kamiya Yutaka Yamada Tetsuya Mori Mai Uzaki Takashi Nirasawa Kiminori Toyooka Kazuki Saito 《Plant Biotechnology》2021,38(3):305
Plants release specialized (secondary) metabolites from their roots to communicate with other organisms, including soil microorganisms. The spatial behavior of such metabolites around these roots can help us understand roles for the communication; however, currently, they are unclear because soil-based studies are complex. Here, we established a multimodal metabolomics approach using imaging mass spectrometry (IMS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) to spatially assign metabolites under laboratory conditions using agar. In a case study using Catharanthus roseus, we showed that 58 nitrogen (N)-containing metabolites are released from the roots into the agar. For the metabolite assignment, we used 15N-labeled and non-labeled LC-MS/MS data, previously reported. Four metabolite ions were identified using authentic standard compounds as derived from monoterpene indole alkaloids (MIAs) such as ajmalicine, catharanthine, serpentine, and yohimbine. An alkaloid network analysis using dot products and spinglass methods characterized five clusters to which the 58 ions belong. The analysis clustered ions from the indolic skeleton-type MIAs to a cluster, suggesting that other communities may represent distinct metabolite groups. For future chemical assignments of the serpentine community, key fragmentation patterns were characterized using the 15N-labeled and non-labeled MS/MS spectra. 相似文献
78.
Ozawa M Honda K Nakai I Kishida A Ohsaki A 《Bioorganic & medicinal chemistry letters》2008,18(14):3992-3994
An indole alkaloid (hypaphorine (1)) was isolated from Brazilian medicinal plant, Erythrina velutina (Leguminosae). This compound was investigated for sleep promoting effects in mice, and the results showed that it significantly increased non-rapid eye movement (NREM) sleep time during the first hour after its administration. The NREM sleep time was enhanced by 33% in the experimental mice when compared to that of the controls. This study therefore confirmed its sleep promoting property. 相似文献
79.
从中国南海棕色扁海绵Phakellia fusca Schimidt的乙醇浸提物中,分离得到3个吡咯生物碱,结合理化性质,波谱分析,文献检索,确定其结构分别为4,5-二溴-1H-吡咯-2-甲酸甲酯(1)、4,5-二溴-3-氰-1H-吡咯-2-甲酸甲酯(2)、4,5-二溴-1H-吡咯-2-甲酰氨(3)。其中化合物(2)未见文献报道。 相似文献
80.
中坝鹅掌叶附子中的生物碱成分 总被引:6,自引:0,他引:6
从中坝鹅掌叶附子(Aconitum carmichaeli Debx.)的块根中分离得到6个二萜生物碱,根据波谱方法分别鉴定为:songoramine(1)、次乌头碱(hypaconitine,2)、karakanine(3)、宋果灵(songorine,4)、尼奥宁(neoline,5)、附子灵(fuzline,6)。其中化合物3为首次从该植物的块根中分离鉴定。 相似文献