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Статті в журналах з теми "Y-Cyclodextrine"
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Sparr, H. J. "Cyclodextrine." Der Anaesthesist 51, no. 11 (November 1, 2002): 929–30. http://dx.doi.org/10.1007/s00101-002-0401-y.
Повний текст джерела
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ZHEKOVA, BORIANA Y., and VESELIN S. STANCHEV. "Reaction Conditions for Maximal Cyclodextrin Production by Cyclodextrin Glucanotransferase from Bacillus megaterium." Polish Journal of Microbiology 60, no. 2 (2011): 113–18. http://dx.doi.org/10.33073/pjm-2011-015.
Повний текст джерелаАнотація:
The effect of the reaction conditions (substrate concentration, enzyme dosage, and pH) on cyclodextrin production by cyclodextrin glucanotransferase from Bacillus megaterium was investigated by applying mathematical modeling methods. Adequate models were developed and they were used for determination of the optimal conditions for maximal formation of beta-cyclodextrins at minimal concentrations of a- and gamma-cydclodextrins. The main factor affecting the ratio of the products was pH of the reaction mixture. At pH 9 the enzyme formed mainly beta- and y-cyclodextrins and the ratio a:beta:gamma was 2.6:83.5:13.9; at pH 5 the ratio changed to 8.6:84.6:6.8. Mathematical models were used for determination of the conditions for maximal conversion of the substrate into cyclodextrins. 45.88% conversion of starch was achieved at 5% substrate concentration, 3.5 U/g enzyme dosage, and pH 7.4.
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IBRAKOVA, Nurgiza F., Galiya G. KUTLUGILDINA та Yuriy S. ZIMIN. "COMPLEXATION OF PRAZIQUANTEL WITH α-, β- AND y-CYCLODEXTRINS IN AQUEOUS-ALCOHOLIC SOLUTIONS". Periódico Tchê Química 17, № 36 (20 грудня 2020): 302–14. http://dx.doi.org/10.52571/ptq.v17.n36.2020.317_periodico36_pgs_302_314.pdf.
Повний текст джерелаАнотація:
Currently, the percentage of infections with invasive (parasitic) diseases is quite large; therefore, the treatment of helminthiases is an urgent problem in veterinary medicine. Parasitic worms inflict significant damage on animal husbandry, leading to the death of animals, shortage of meat, dairy products, and wool. The most common active ingredient in antihelmintics is praziquantel, which is well known as an effective broad-spectrum anthelmintic. At the same time, praziquantel has low solubility in water and a pronounced bitter taste, which represents a significant obstacle in developing liquid forms of drugs that are convenient for administration to animals. One way to solve these problems is the complexation of medicinal substances with various (natural and synthetic) compounds. In this regard, this paper aims to study the complexation of praziquantel with α-, β-, and -cyclodextrins in aqueous-alcoholic solutions. The studies were carried out by the method of ultraviolet spectroscopy. It was found that the addition of cyclodextrins to aqueous-alcoholic solutions of praziquantel leads to spectral changes indicating the presence of intermolecular interactions and complexation. The isomolar series method showed that in dilute solutions, praziquantel forms complex compounds with cyclodextrins 1:1, that is, one molecule of praziquantel falls on one molecule of α-, β- or y-cyclodextrin. The stability constants of the resulting complexes were calculated using the molar ratio method. It is shown that in the range of 296-316 K, the composition of complex compounds remains unchanged (1:1), and their stability decreases with increasing temperature. The study of the temperature dependences of the stability constants made it possible to determine the standard values of changes in the Gibbs energy, enthalpy, and complexation entropy.
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Viola, Luis, and Rita H. de Rossi. "Effect of cyclodextrin on elimination reactions." Canadian Journal of Chemistry 77, no. 5-6 (June 1, 1999): 860–67. http://dx.doi.org/10.1139/v99-085.
Повний текст джерелаАнотація:
The reaction of 1-bromo-2-X-2-(Y-phenyl) ethane derivatives (1: X = Y = H; 2: X = Ph, Y = H; 3: X = H, Y = 4-Ac; 4: X = H, Y = 3-NO2; 5: X = H, Y = 4-NO2; 6: X = H, Y = 3-Me; 7: X = H, Y = 4-Me) in basic solution was studied, and in most cases, only the elimination product is formed. Only (2-bromo-1-phenylethyl)benzene, 2, yielded significant substitution product, and this yield decreased with the concentration of HO-. Addition of cyclodextrin (β-CD) diminished (about half for 0.02 M cyclodextrin concentration) the reaction rate of all substrates but 4 and 5. In the latter two cases, the rate rises. The observed rate-constant value at 0.5 M NaOH is 6.78 × 10-4 s-1 (at 40°C) and 1.80 × 10-3 s-1 (at 25°C) for 4 and 5, respectively. Under the same reaction conditions but with 0.01 M β-CD, the corresponding rates were 7.70 × 10-4 s-1 and 5.20 × 10-3 s-1. The elimination yield for 2 increased from 64 to 98% when the β-CD changed from zero to 0.02 M at 0.5 M NaHO. Also, there was an increase in the relative elimination products of 20-40% for compounds 6 and 7. The Hammet ρ values were 1.3 and 2.3 for the reaction in pure solvent and in the presence of β-cyclodextrin, indicating an increase in the negative character of the transition state for the reactions in the latter conditions. The results are interpreted in terms of the formation of an inclusion complex whose structure depends on the substrate.Key words: cyclodextrin, elimination reactions, inhibition, catalysis.
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Ngo, Huy T., Philip Clements, Christopher J. Easton, Duc-Truc Pham та Stephen F. Lincoln. "Supramolecular Chemistry of Pyronines B and Y, β-Cyclodextrin and Linked β-Cyclodextrin Dimers". Australian Journal of Chemistry 63, № 4 (2010): 687. http://dx.doi.org/10.1071/ch09467.
Повний текст джерелаАнотація:
The complexation of cationic pyronine B (PB+) and pyronine Y (PY+) by β-cyclodextrin (βCD) and two linked βCD dimers, N,N′-bis((2AS,3AS)-3A-deoxy-β-cyclodextrin-3A-yl)succinamide, 33βCD2suc, and N,N′-bis(6A-deoxy-β-cyclodextrin-6A-yl)succinamide, 66βCD2suc, in aqueous solution has been studied by UV-vis, fluorescence, and 1H NMR spectroscopy. The complexation constants for the 1:1 complexes: βCD.PB+, 33βCD2suc.PB+, 66βCD2suc.PB+, and the analogous PY+ complexes are reported as are the dimerization constants for PB+ and PY+. The modes of complexation, dimerization, and fluorescence quenching are discussed.
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Delrivo, Alicia, Gladys Granero та Marcela Longhi. "Studies of ternary systems of sulfadiazine with β-cyclodextrin and aminoacids". Ars Pharmaceutica (Internet) 57, № 4 (20 грудня 2016): 167–76. http://dx.doi.org/10.30827/ars.v57i4.5561.
Повний текст джерелаАнотація:
Introduction: Cyclodextrins (CD), are known to form inclusion complexes with a variety of guest molecules both in solution and in the solid state. This can lead to the alteration of properties of guest molecules. Unfortunately, the complexation efficiency of CD is rather low, and can be enhanced by formation of ternary complexes using aminoacids (AA). Sulfadiazine (SDZ) is an antibiotic with extremely low water solubility which limits its therapeutic applications and bioavailability. Objetives: The aim of this work was to increase the aqueous solubility of SDZ by preparing ternary complexes of this drug with β-cyclodextrin (βCD) and an AA as a third auxiliary substance. Materials y Methods: Complex formation was studied by phase solubility analysis (PSA), nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), thermogravimetric analysis (TG) and scanning electron microscopy (SEM). Results: The apparent stability constants (KC) of the multicomponent complexes were calculated from the solubility diagrams. By the analysis of the NMR spectra, it could be said that the shifts of some protons evidenced the important role of the AA in the formation of multicomponent complexes. Among the AA, Arginine (ARG) proved to have better solubilizing properties for SDZ, reaching an improvement up to 70 times. The use of DSC, TG and SEM suggested the formation of new solid phases between SDZ:βCD:AA. Conclusions: As a result of this research, it was determined that ternary products were more effective in improving drug solubility than the corresponding SDZ:βCD binary system.
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Duan, Zhengyang, Mingyao Song, Tianguo Li, Shuli Liu, Xiaojun Xu, Ronggao Qin, Changhua He, Yao Wang, Longqian Xu та Mengjiao Zhang. "Characterization and adsorption properties of cross-linked yeast/β-cyclodextrin polymers for Pb(ii) and Cd(ii) adsorption". RSC Advances 8, № 55 (2018): 31542–54. http://dx.doi.org/10.1039/c8ra06171h.
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Benkovics, Gábor, Damien Afonso, András Darcsi, Szabolcs Béni, Sabrina Conoci, Éva Fenyvesi, Lajos Szente, Milo Malanga та Salvatore Sortino. "Novel β-cyclodextrin–eosin conjugates". Beilstein Journal of Organic Chemistry 13 (15 березня 2017): 543–51. http://dx.doi.org/10.3762/bjoc.13.52.
Повний текст джерелаАнотація:
Eosin B (EoB) and eosin Y (EoY), two xanthene dye derivatives with photosensitizing ability were prepared in high purity through an improved synthetic route. The dyes were grafted to a 6-monoamino-β-cyclodextrin scaffold under mild reaction conditions through a stable amide linkage using the coupling agent 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride. The molecular conjugates, well soluble in aqueous medium, were extensively characterized by 1D and 2D NMR spectroscopy and mass spectrometry. Preliminary spectroscopic investigations showed that the β-cyclodextrin–EoY conjugate retains both the fluorescence properties and the capability to photogenerate singlet oxygen of the unbound chromophore. In contrast, the corresponding β-cyclodextrin–EoB conjugate did not show either relevant emission or photosensitizing activity probably due to aggregation in aqueous medium, which precludes any response to light excitation.
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Wang, Yan, Yuyang Liu, Jianghu Liang, and Minhao Zou. "A cyclodextrin-core star copolymer with Y-shaped ABC miktoarms and its unimolecular micelles." RSC Advances 7, no. 19 (2017): 11691–700. http://dx.doi.org/10.1039/c6ra28456f.
Повний текст джерелаАнотація:
A β-cyclodextrin-core star copolymer with Y-shaped ABC miktoarms was designed which exhibits unimolecular micelles in aqueous solution. It is a good platform for unimolecular container encapsulating hydrophobic molecules with release of the payload exhibiting pH-sensitivity.
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Chekroud, Hassina, Fayçal Djazi, Bouhadiba Abd alaziz, Karima Horchani-Naifer, Zeghdoudi Rachida та Remache Malika. "Modeling and Optimisation of Comlexity by the β-Cyclodextrin of an Organic Pollutant Model: m-Methyl Red". Chemistry & Chemical Technology 16, № 2 (15 червня 2022): 195–202. http://dx.doi.org/10.23939/chcht16.02.195.
Повний текст джерелаАнотація:
Studies of cyclodextrin chemistry using quantum chemical methods are mainly adopted to investigate the formation of the inclusion complex causing changes in the physicochemical properties of the cyclodextrin guest. In this paper, we conducted a computational modeling study of the inclusion complexes of β-cyclodextrin (β-CD) with m-Methyl Red (m-MR) by using parametric method 6 (PM6), the semi empirical molecular orbital calculations and the natural bond orbital method (NBO). The inclusion process is carried out by maintaining the coordinates of the β-CD fixed and by displacing the guest molecule. The different relative positions between m-MR and β-CD are measured with respect to the distance between the reference atom (N) in the guest molecule and the origin of the coordinates from the equatorial plane of β-CD. The m-MR/β-CD (B) inclusion complex has a lower negative value of ΔG compared to another m-MR/β-CD (A) complex, highlighting the spontaneous behavior of the inclusion process. In addition, during the process of inclusion, the complexation energy is negative, which allows us to affirm that the complexation of m-MR in the β-CD is thermodynamically favorable. Among two directions A and B, the minimum energy generated from the PM6 was obtained in the orientation B and the guest molecule is partially encapsulated in the cavity of β-CD. In the NBO analysis, the stabilization energy is also usually used to characterize the hydrogen bond interaction between a lone pair (LP(Y)) of an atom Y and an anti-bonding orbital (BD٭(X-H)).
Дисертації з теми "Y-Cyclodextrine"
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Riquel-Loizelet, Noelline. "Assemblages supramoleculaires de type (pseudo)polyrotaxane : vers la synthèse de modèles biocompatibles de cellules musculaires." Electronic Thesis or Diss., université Paris-Saclay, 2025. http://www.theses.fr/2025UPASF004.
Повний текст джерелаАнотація:
En s'inspirant du vivant, le biomimétisme invite à développer de nouvelles familles de matériaux, pour des applications variées. Dans ce contexte, des assemblages supramoléculaires de type (pseudo)polyrotaxanes, semblables à des colliers de perles, pourraient permettre d'obtenir des matériaux innovants stimulables, par exemple des matériaux capables de mimer le mouvement d'un muscle sous l'effet d'un stimulus. L'objectif de cette thèse a été de synthétiser des (pseudo)polyrotaxanes biocompatibles et thermostimulables, à partir de γ-cyclodextrine (γ-CD) et de copolymères à blocs, constitués de poly(N-isopropylacrylamide) (PNIPAM) et de poly(oxyde d'éthylène) (POE), afin d'obtenir des matériaux dont les propriétés mécaniques pourraient être modifiées de manière réversible en réponse à un stimulus extérieur. Le PNIPAM a été choisi pour son caractère thermosensible, tandis que le POE, a lui été choisi pour son affinité particulière avec les cyclodextrines, facilitant ainsi leur enfilage. Au cours de ces travaux de thèse, la formation d'assemblages supramoléculaires avec des CDs a d'abord été étudiée en présence d'homopolymères de PNIPAM et de POE (de longueurs variables et d'extrémités variables), puis avec des copolymères diblocs, puis triblocs (ABA ou BAB), synthétisés selon différentes voies (couplage, ATRP, RAFT). La caractérisation des édifices a été réalisée en mobilisant diverses techniques d'analyse : RMN 1H, MALDI-TOF, DRX, CES et TGA. Les résultats ont montré que les γ-CDs s'enfilaient majoritairement sur le bloc de POE qu'il soit situé au centre ou aux extrémités des différents copolymères avec un nombre de CDs que l'on peut contrôler, en fonction de la stœchiométrie (γ-CDs) : (polymère) adoptée avant la complexation, la longueur des chaines, la température. Plusieurs architectures ont été proposées pour ces assemblagesInspired by the living world, biomimicry encourages the development of new families of materials for a wide range of applications. In this context, (pseudo)polyrotaxane-type supramolecular assemblies, like strings of pearls, could make it possible to obtain innovative stimulable materials, for example materials capable of mimicking the movement of a muscle under the effect of a stimulus. The aim of this thesis was to synthesize biocompatible, thermostimulable (pseudo)polyrotaxanes from γ-cyclodextrin (γ-CD) and block copolymers, consisting of poly(N-isopropylacrylamide) (PNIPAM) and poly(ethylene oxide) (POE), in order to obtain materials whose mechanical properties could be reversibly modified in response to an external stimulus. PNIPAM was chosen for its thermosensitive properties, while POE was chosen for its particular affinity with cyclodextrins, making them easier to thread. During this thesis work, the formation of supramolecular assemblies with CDs was first studied in the presence of homopolymers of PNIPAM and POE (of variable lengths and variable ends), then with diblock, then triblock copolymers (ABA or BAB), synthesized by different routes (coupling, ATRP, RAFT). Characterization of the edifices was carried out by mobilizing various analytical techniques: 1H NMR, MALDI-TOF, DRX, CES and TGA. The results showed that γ-CDs threaded predominantly onto the POE block whether located in the center or at the ends of the various copolymers with a number of CDs that could be controlled, depending on the (γ-CDs):(polymer) stoichiometry adopted prior to complexation, chain length, temperature. Several architectures have been proposed for these assemblies
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Wong, Ka Hong. "Development of halofuginone, artesunate liposomes and crocetin y-cyclodextrin inclusion complex." HKBU Institutional Repository, 2020. https://repository.hkbu.edu.hk/etd_oa/889.
Повний текст джерелаАнотація:
The water solubility of drug molecules plays an important role in consideration of formulation development to treat a wide range of diseases. In this project, two kinds of drug delivery systems, cyclodextrins and liposomes, were developed for insoluble drug delivery to treat Alzheimer's disease (AD) and colorectal cancer (CRC), respectively. AD is an irreversible neurodegenerative disorder associated with the accumulation of amyloid-beta (A??) fibrils. Approximately 10% of people aged 65 and above have AD. Crocetin (CRT) is an active compound isolated from the fruits of gardenia (Gardenia jasminoides Ellis) and the stigmas of saffron (Crocus sativus L.). It has been reported to show various neuroprotective activities. However, poor water solubility and bioavailability are the major obstacles in developing pharmaceutical formulations of CRT. To address the issues, CRT liposomal formulations and CRT-cyclodextrin inclusion complexes were developed and evaluated. CRT-cyclodextrin inclusion complexes significantly increased the water solubility of CRT from the range ??g/mL to mg/mL. The CRT-??-cyclodextrin inclusion complex (1:3 molar ratio of CRT/??-cyclodextrin) was chosen for further studies as it showed the highest encapsulation efficiency (94.73 ?? 0.86%). The formulation had no toxicity to neuronal cells nor AD model cells within the experimental concentration range (0.625 to 100 ??M of CRT). It could downregulate the expression of C-terminus fragments and decrease both intracellular and extracellular levels of A??, which are hallmarks of AD. It also showed dose-dependent neuroprotective and antioxidant effects against H2O2-induced cell death. Pharmacokinetics and biodistribution studies showed that this CRT-??-cyclodextrin inclusion complex was suitable for intravenous administration. The formulation significantly increased the bioavailability of CRT and facilitated CRT crossing the blood-brain barrier to enter the brain. Similar to AD, CRC is increasingly prevalent with aging populations. Approximately 60% of CRC patients are aged 70 and above. Halofuginone (HF) is an active pharmaceutical ingredient (API) originated from Chinese quinine (Dichroa febrifuga Lour.) and artesunate (ART) is a semi-synthetic derivative of artemisinin (ATS) extracted from annual wormwood (Artemisia annua L.). Both APIs show anticancer activities by inhibiting the growth of CRC. However, low aqueous stability limits their applications. Liposome formulation with surface functionalization by CPP2 cell-penetrating peptide was developed to deliver HF and ART for targeted CRC therapy. CPP2 is a peptide that can selectively penetrate colon cancer cells. The liposomal drug formulations had uniform particle size (about 100 nm), high encapsulation efficiency (over 80%) and good stability upon 14 days of storage. In cellular uptake study, CPP2-modified liposome showed stronger permeability and selectivity to colon cancer lines without inducing lysosomal degradation. CPP2 surface-modified liposomal drugs demonstrated greater anticancer activities than free form of drugs or conventional liposomal drugs. Combinations of HF and ART formulations notably decreased cancer cell viability as compared to single formulation alone, which indicated that HF and ART formulations exhibited synergistic anticancer effects at specific ratios. To conclude, the drug delivery systems, cyclodextrins and peptide-modified liposomes, which were developed for AD and CRC treatment, successfully improved the aqueous solubility of insoluble APIs extracted from Chinese medicinal plants.
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Rodríguez, Bonilla María Pilar. "Molecular nanoencapsulation of stilbenes by cyclodextrins : study of biochemical, chromatographic and antioxidant applications= Nanoencapsulación molecular de estilbenos por ciclodextrinas: aplicaciones bioquímicas, cromatográficas y antioxidantes." Doctoral thesis, Universidad de Murcia, 2015. http://hdl.handle.net/10803/363919.
Повний текст джерелаАнотація:
INTRODUCCIÓN Y OBJETIVOS En los últimos años ha cobrado gran fuerza la aparición de los alimentos funcionales, entendiéndose como tales aquellos que le confieren al consumidor un beneficio para la salud más allá de sus propiedades puramente nutritivas. Uno de los grupos de alimentos funcionales que más cuota de mercado está obteniendo es el de los enriquecidos en sustancias bioactivas con un alto valor biológico. En esta tesis doctoral se propone la investigación necesaria para el diseño de alimentos funcionales enriquecidos en diversos tipos de estilbenos, moléculas que han demostrado poseer propiedades beneficiosas para la salud. El estudio de los estilbenos favorecerá, además, su uso en las industrias farmacéutica y cosmética. El hecho de que, por una parte, los miembros de esta familia de compuestos muestren un alto grado de inestabilidad y que, por otra, la gran mayoría de ellos presenten un carácter poco hidrofílico, dificulta el enriquecimiento de productos con estas moléculas por lo que se hace necesario el diseño de nuevas estrategias para que puedan ser empleados, como es el caso de la encapsulación molecular. Por ello, el objetivo general de la presente tesis es la nanoencapsulación de diferentes estilbenos mediante ciclodextrinas con el fin de incrementar, por un lado, su estabilidad frente a diversos agentes físico-químicos y, por otro, la solubilidad de los derivados más hidrofóbicos. METODOLOGÍA La metodología utilizada se ha basado en ensayos fluorimétricos, espectrofotométricos y cromatográficos para caracterización de la formación de distintos complejos de inclusión de los estilbenos con diferentes tipos de ciclodextrinas naturales y modificadas. También se han utilizado diferentes métodos (ORAC, ABTS y FRAP) para evaluar la capacidad antioxidante de estilbenos, en ausencia y presencia de ciclodextrinas. Por último se han empleado técnicas de docking molecular. CONCLUSIONES La conclusión principal de esta Tesis Doctoral es que se ha conseguido encapsular diferentes estilbenos (oxyresveratrol, resveratrol, pinosilvina y pterostilbeno) mediante distintos tipos de ciclodextrinas, lo que abre la oportunidad al uso de estos importantes compuestos bioactivos en la industria alimentaria, farmacéutica y cosmética. Además sea demostrado la utilidad de los nanocomplejos ciclodextrina/estíbenos en áreas como la cromatografía, la enzimología o la actividad antioxidante.INTRODUCTION AND OBJECTIVES In recent years the growth of the functional foods industry has increased research into new compounds with high added value for use in the fortification of traditional products. One of the most promising functional food groups are those enriched in antioxidant compounds of a lipophilic nature. As a result, in this thesis are required for the design of functional foods rich in various types of stilbenes, molecules that have been shown to have large beneficial properties for health research is proposed. In spite of the numerous advantages reported for such antioxidant molecules, they may also have disadvantages that impede their use in functional foods, although these problems may well avoided by the use of encapsulant agents such as cyclodextrins. Therefore, the overall objective of this thesis is the nanoencapsulation of different stilbenes by cyclodextrins in order to increase firstly, its stability against various physical and chemical agents and, secondly, the solubility of the more hydrophobic derivatives. MATERIAL AND METHODS The methodology is based on fluorimetric and chromatographic assays for characterization of the formation of inclusion complexes of various stilbene (oxyresveratrol, resveratrol pterostilbene and pinosylvin) with different types of natural and modified cyclodextrins. Have also been used different methods, ORAC, ABTS and FRAP, to evaluate the antioxidant capacity of stilbenes, in the absence and presence of cyclodextrins. Finally, we have used a molecular docking. CONCLUSIONS The main conclusion of this thesis is have been encapsulated different stilbene (oxyresveratrol, resveratrol and pterostilbene pinosylvin) through different types of cyclodextrins, which opens the opportunity to use these important bioactive compounds in food, pharmaceutical and cosmetic. In addition we have demonstrated the utility of nanocomplex stilbene/cyclodextrin in areas such as chromatography, enzymology or antioxidant activity.
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Ramírez, Estrada Karla. "Cultivos celulares de Taxus spp., una eficaz herramienta biotecnológica para la producción de taxanos y el desarrollo de estudios básicos sobre su biosíntesis." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/300431.
Повний текст джерелаАнотація:
Los cultivos de células vegetales pueden constituir plataformas biotecnológicas ecológicas para la producción de metabolitos secundarios de plantas con actividad farmacológica, así como un excelente sistema para ampliar el conocimiento del metabolismo secundario. El taxol y taxanos relacionados son metabolitos secundarios vegetales con una notable actividad anticancerígena. A pesar de la importancia de estos compuestos, su producción biotecnológica todavía necesita ser optimizada y aún se desconocen algunos aspectos de su biosíntesis. En este trabajo hemos estudiado la respuesta a la acción de la beta-metil-ciclodextrina (CD) y coronatina (CORO) de dos cultivos celulares de Taxus (T. media y T. globosa) con el fin de encontrar alternativas para la producción de taxanos; también hemos caracterizado el gen TB768, que previamente fue seleccionado a partir de un estudio de cDNA-AFLP, como candidato a codificar para una enzima implicada en la biosíntesis de taxol. La producción de taxanos, fue mayor en las líneas celulares de T. media que en T. globosa e incrementó significativamente por la adición simultánea de los elicitores CD y CORO, correlacionando con la expresión de los genes conocidos de la biosíntesis de taxol. El análisis funcional del gen TB768 demostró, confirmando las predicciones in silico, que este gen codifica para una acil-CoA ligasa citoplasmática, capaz de convertir la β-fenilalanina en su éster de CoA, un precursor de la cadena lateral del taxol. De esta forma la nueva proteína caracterizada, beta-fenilalalina CoA ligasa (TBPCCL), estaría implicada en una de las últimas etapas de la ruta biosintética de taxanos. Estos estudios contribuyen a la creación de nuevos y mejores sistemas de producción sostenible de taxol y taxanos relacionados; mediante sistemas de elicitación o de ingeniería metabólica.Plant cell cultures constitute eco-friendly biotechnological platforms for the production of plant secondary metabolites with pharmacological activities, as well as a suitable system for extending our knowledge of secondary metabolism. Taxol and related taxanes are plant secondary metabolites with a remarkable anticancer activity. Despite the importance of these phytochemicals, their biotechnological production still requires optimization and several aspects of their biosynthesis remain unknown. In this work, we studied the response of two Taxus cell cultures (T. media and T. globosa) to the addition of β-methyl cyclodextrin (CD) and coronatine (CORO) with the aim of finding alternative systems for taxane production; we also characterized the TB768 gene, which a previous cDNA-AFLP analysis revealed to be a putative candidate for encoding a taxol biosynthetic enzyme. Taxane production was higher in the T. media than the T. globosa cell line, and was significantly enhanced by the simultaneous addition of both elicitors (CD and CORO); the expression of known taxol biosynthetic genes was correlated with the improved taxane production. Confirming in silico predictions, functional analysis of the TB768 gene showed that it encodes a cytoplasmic acyl-CoA ligase able to convert β-phenylalanine into its respective CoA ester derivative, a precursor of the taxol lateral chain. Therefore, this newly characterized enzyme, β-phenylalanine CoA ligase (TBPCCL), must be involved in one of the last steps of the taxane biosynthetic pathway. These studies are a contribution to the establishment of sustainable taxol production systems by elicitation or metabolic engineering approaches.
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Busche, Bradley James. "Compatibilization of polystyrene/poly(dimethylsiloxane) using star polymers containing a y-cyclodextrin core and polystyrene arms." 2009. http://www.lib.ncsu.edu/theses/available/etd-06202009-092653/unrestricted/etd.pdf.
Повний текст джерелаЧастини книг з теми "Y-Cyclodextrine"
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Schiller, Robert L., Stephen F. Lincoln, and John H. Coates. "The Inclusion of Pyronine B and Pyronine Y by Beta- and Gamma- Cyclodextrins. A Kinetic and Equilibrium Study." In Inclusion Phenomena in Inorganic, Organic, and Organometallic Hosts, 59–63. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3987-5_6.
Повний текст джерела
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Atwood, Jerry L., and J. Eric D. Davies. "Erratum to: The Inclusion of Pyronine B and Pyronine Y by Beta- and Gamma- Cyclodextrins. A Kinetic and Equilibrium Study." In Inclusion Phenomena in Inorganic, Organic, and Organometallic Hosts, 443. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3987-5_72.
Повний текст джерелаТези доповідей конференцій з теми "Y-Cyclodextrine"
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Tarun, E. I., P. A. Vinogradov, D. A. Karabun, T. M. Halavach, and R. V. Romanovich. "ANTIOXIDANT ACTIVITY OF WHEY AND COLOSTRUM HYDROLYZATES COMPLEXES with y-CYCLODEXTRIN." In SAKHAROV READINGS 2022: ENVIRONMENTAL PROBLEMS OF THE XXI CENTURY. International Sakharov Environmental Institute of Belarusian State University, 2022. http://dx.doi.org/10.46646/sakh-2022-2-10-14.
Повний текст джерелаАнотація:
The comparative study of the antioxidant activity of whey protein concentrate, native colostrum, their ultrafiltered hydrolysates, as well as complexes of ultrafiltered hydrolysates with Y-cyclodextrin was carried out. The dependences of the fluorescence intensity of fluorescein on the logarithm of the concentration of all samples were obtained, from which the IC50 values were graphically determined, which were in the range of 7,2-103,4 gg/ml. Complexes of ultrafiltrate hydrolysates with Y-cyclodextrin restored fluorescein fluorescence to 88-96 % at a sample concentration of 0,68-0,75 mg/ml.
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Novo, Mercedes, Belén Reija, Wajih Al-Soufi, and José Vazquez Tato. "Study of the Complexation of Pyronines Y and B with Beta-Cyclodextrin by Fluorescence Spectroscopy." In The 8th International Electronic Conference on Synthetic Organic Chemistry. Basel, Switzerland: MDPI, 2004. http://dx.doi.org/10.3390/ecsoc-8-01997.
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