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紫荆花红色素开发利用的研究 总被引:9,自引:0,他引:9
首次报道紫荆花红色素的提取纯化方法及红色素的理化性质,并与玫瑰茄红色素作对比研究,证实同属于花青甙类化合物,又经急性毒性试验证明其毒性极低,故紫荆花天然红色素具有开发利用的价值。 相似文献
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Atoumane Ndiaye Alle Dioum Corneliu I. Oprea Anca Dumbrava Jeanina Lungu Adrian Georgescu Florin Moscalu Mihai A. Gîru Aboubaker Chedikh Beye Issakha Youm 《Molecules (Basel, Switzerland)》2021,26(1)
The theoretical study of chrysanthemin (cyanidin 3-glucoside) as a pigment for TiO2-based dye-sensitized solar cells (DSSCs) was performed with the GAUSSSIAN 09 simulation. The electronic spectra of neutral and anionic chrysanthemin molecules were calculated by density functional theory with B3LYP functional and DGDZVP basis set. A better energy level alignment was found for partially deprotonated molecules of chrysanthemin, with the excited photoelectron having enough energy in order to be transferred to the conduction band of TiO2 semiconductor in DSSCs. In addition, we used the raw aqueous extracts of roselle (Hibiscus sabdariffa) calyces as the source of chrysanthemin and the extracts with various pH values were tested in DSSCs. The extracts and photosensitized semiconductor layers were characterized by UV-Vis spectroscopy, and DSSCs based on raw extracts were characterized by current density-voltage measurements. 相似文献
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A recently described plant cell wall dissolution system has been modified to use perdeuterated solvents to allow direct in-NMR-tube dissolution and high-resolution solution-state NMR of the whole cell wall without derivatization. Finely ground cell wall material dissolves in a solvent system containing dimethylsulfoxide-d(6) and 1-methylimidazole-d(6) in a ratio of 4:1 (v/v), keeping wood component structures mainly intact in their near-native state. Two-dimensional NMR experiments, using gradient-HSQC (heteronuclear single quantum coherence) 1-bond (13)C--(1)H correlation spectroscopy, on nonderivatized cell wall material from a representative gymnosperm pinus taeda (loblolly pine), an angiosperm Populus tremuloides (quaking aspen), and a herbaceous plant Hibiscus cannabinus (kenaf) demonstrate the efficacy of the system. We describe a method to synthesize 1-methylimidazole-d(6) with a high degree of perdeuteration, thus allowing cell wall dissolution and NMR characterization of nonderivatized plant cell wall structures. 相似文献
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The use of new food grade polysaccharides (mucilage) obtained from Hibiscus esculentus and Trigonella foenum graceum,commonly called Okra and Fenugreek,respectively,as flocculants was described.These polysaccharides were used for removal of solids (suspended solids (SS) and total dissolved solids (TDS)) and dyes from real textile effluents and aqueous solutions of different class of synthetic dyes.Influences of varying polysaccharide concentration,contact time and pH on removal of pollutant from the textile wastewater were investigated.Results showed that polysaccharides (mucilage) obtained from Okra and Fenugreek were capable of removing 90%-94% of SS,30%-44% of TDS and 30%-35% of dye using a very low concentration of polysaccharide.X-ray diffraction (XRD) patterns of solid waste material obtained before and after the treatment with polysaccharides were used as a supportive evidence to explain the mechanism of flocculation. 相似文献
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Li L Huang X Sattler I Fu H Grabley S Lin W 《Magnetic resonance in chemistry : MRC》2006,44(6):624-628
From the stem and bark of the mangrove plant Hibiscus tiliaceus, a new friedelane-type triterpene named 27-oic-3-oxo-28-friedelanoic acid (1) together with eight known triterpenoids involving five friedelane-type derivatives was isolated. The structure of 1 was determined by extensive 2D NMR (DQF-COSY, HMQC, HMBC, and NOESY) data analyses. All the compounds were obtained from mangrove plants for the first time. 相似文献
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José A. Murillo Pulgarín Luisa F. García Bermejo Armando Carrasquero Durán 《Analytical letters》2017,50(1):186-196
This study reports a simple and rapid method for the determination of the antioxidant activity of the phenolics present in plants of the Hibiscus genus. The protocol is based on the ability of the phenolic compounds to inhibit luminol chemiluminescence through the inactivation of free radicals in a flow injection system. Using the optimized operational conditions, the antioxidant activities of several phenolics were measured. The results were explained on the basis of structure–reactivity relationships. The antioxidant activities of dried flowers of Hibiscus rosa-sinensis and Hibiscus sabdariffa were evaluated. The protocol was validated by the 2,2-diphenyl-1-picrylhydrazyl-hydrate free radical assay. The differences in the antiradical activities were explained based on the concentrations of total polyphenol and flavonoid concentrations determined by spectrophotometric methods. It was concluded that the chemiluminescence method was complementary for the evaluation of hydrophilic antioxidants in plants. 相似文献
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Duanyang Wang Maki Nagata Masako Matsumoto Yhiya Amen Dongmei Wang Kuniyoshi Shimizu 《Molecules (Basel, Switzerland)》2022,27(18)
Hibiscus sabdariffa L. (HS) has a long history of edible and medicinal uses. In this study, the biological activities of the extracts, chromatographic fractions, and hibiscus acid obtained from HS were evaluated for their potential bioactivities. Their ability to promote extracellular matrix synthesis in skin fibroblasts was evaluated by enzyme-linked immunosorbent assays. Their anti-inflammatory activity was evaluated in a nitric oxide (NO)–Griess inflammatory experiment. Furthermore, hibiscus acid was found to have a strong anti-oxidative stress effect through the establishment of an oxidative stress model induced by hydrogen peroxide. Several assays indicated that hibiscus acid treatment can effectively reduce extracellular adenosine triphosphate (ATP) secretion and carbonyl protein production, as well as maintain a high level of reduced/oxidized glutathione (GSH/GSSG) in skin cells, thus providing a possible mechanism by which hibiscus acid can counter antioxidative stress. The present study is the first to explore the reversing skin aging potential and the contributory component of HS. 相似文献
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E. A. Pshenichnov E. M. Sultanova O. N. Veshkurova M. V. Ionov B. A. Salakhutdinov Sh. I. Salikhov 《Chemistry of Natural Compounds》2004,40(1):63-65
The fungitoxicity of a biocidal peptide from kenaf Hibiscus cannabinus L. seeds was investigated. Its influence on the distribution of calcium ions in mycelial cells of the fungus Verticilluim dahliae Kleb. was examined. 相似文献
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Dong‐Li Li Xiao‐Ming Li Tie‐Gang Li Hong‐Yue Dang Bin‐Gui Wang 《Helvetica chimica acta》2008,91(10):1888-1893
Cultivation of the fungal strain Eurotium rubrum, an endophytic fungus that was isolated from the inner tissue of stems of the mangrove plant Hibiscus tiliaceus, resulted in the isolation of two new dioxopiperazine derivatives, namely, dehydrovariecolorin L ( 1 ) and dehydroechinulin ( 2 ), together with eight known dioxopiperazine compounds including variecolorin L ( 3 ), echinulin ( 4 ), isoechinulin A ( 5 ), dihydroxyisoechinulin A ( 6 ), preechinulin ( 7 ), neoechinulin A ( 8 ), neoechinulin E ( 9 ), and cryptoechinuline D ( 10 ). The structures of the isolated compounds were determined by extensive analysis of their spectroscopic data as well as by comparison with literature. Compounds 1, 2, 9 , and 10 were investigated for their α,α‐diphenyl‐β‐picrylhydrazyl (DPPH) radical‐scavenging activity. In addition, the new compounds, 1 and 2 , were evaluated for their cytotoxic activity against the P‐388, HL‐60, and A549 cell lines. 相似文献