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Leather production for human protection has been an essential industrial activity since the start of civilization, yet classical leavering methods induce pollution of ecosystems by dyes, chromium-containing wastewater, and solid waste. Here, we review sustainable leather production using polysaccharides and modified polysaccharides, which are cheap, easy to obtain, and non-toxic. Polysaccharides include starch, chitosan, cellulose, and cyclodextrins. We discuss application for leather tanning, prevention of leather mildew, leather finishing and dyeing, and wastewater treatment. The leather properties meet the requirements of garment leathers, with tear strength higher than 18 N per mm and tensile strength higher than 6.5 MPa. [ABSTRACT FROM AUTHOR]

Paclitaxel (PCTX) is one of the most prevalently used chemotherapeutic agents. However, its use is currently beset with a host of problems: solubility issue, microplastic leaching, and drug resistance. Since drug discovery is challenging, we decided to focus on repurposing the drug itself by remedying its drawbacks and making it more effective. In this study, we have harnessed the aqueous solubility of sugars, and the high affinity of cancer cells for them, to entrap the hydrophobic PCTX within the hydrophilic shell of the carbohydrate β -cyclodextrin. We have characterized this novel drug formulation by testing its various physical and chemical parameters. Importantly, in all our in vitro assays, the conjugate performed better than the drug alone. We find that the conjugate is internalized by the cancer cells (A549) via caveolin 1-mediated endocytosis. Thereafter, it triggers apoptosis by inducing the formation of reactive oxygen species. Based on experiments on zebrafish larvae, the formulation displays lower toxicity compared to PCTX alone. Thus, our "Trojan Horse" approach, relying on minimal components and relatively faster formulation, enhances the anti-tumor potential of PCTX, while simultaneously making it more innocuous toward non-cancerous cells. The findings of this study have implications in the quest for the most cost-effective chemotherapeutic molecule. [ABSTRACT FROM AUTHOR]

Hemin, a heme-like compound with significant biological activity, shows promise as an iron supplement for humans. Nonetheless, its poor solubility in water greatly impedes its absorption and utilization. To surmount this obstacle, researchers have chosen various cyclodextrins with distinct cavity sizes and derivative groups to act as hosts, forming inclusion complexes with hemin chloride. Among these, γ-cyclodextrin has been identified as the optimal carrier, based on a thorough evaluation of its encapsulation efficiency, solubility, and molecular docking. Multiple characterization techniques further confirmed the formation of these inclusion complexes. Results from IEC-6 cell experiments indicated that the cytotoxicity of the inclusion complexes was lower than that of FeSO4. Static and dynamic gastrointestinal simulation digestion systems were established, and the results showed that the bioavailability of the inclusion complex was significantly higher than that of raw hemin. Additionally, only about 0.29% of hemin chloride is digested by gastric enzymes, whereas 9.52% is digested by pancreatic enzymes in the static gastrointestinal simulation digestion system, with similar outcomes observed in the dynamic system. These findings suggest that targeted digestion in the intestine significantly enhances the bioavailability of hemin chloride by forming inclusion complexes in vitro. [ABSTRACT FROM AUTHOR]

The regioselective radical CH trifluoromethylation of aromatic compounds have been shown to proceed in good yield and high regioselectivity when cyclodextrin (CD) is present. Yet, the reaction mechanism and the role of CD during the reaction have remained obscure. To this end, here we performed density functional theory (DFT) calculations to the conformations obtained by semiempirical quantum mechanical molecular dynamics calculations to reveal the reaction mechanism and the role of CD in controlling regioselectivity. The results show that metal salt increases the yield but do not affect the regioselectivity, which we further confirmed by an experiment. In contrast, multiple CD‐substrate complex conformations and reaction pathways were obtained, and CD was shown to contribute to improving the regioselectivity by stabilizing the intermediate state via encapsulation. The present study indicates that CDs can increase the regioselectivity by stabilizing the intermediate and product states while only marginally affecting the transition state. [ABSTRACT FROM AUTHOR]

Desolvation processes, though common in self‐assembled biological structures, are rarely evidenced and utilized in the design of crystalline architectures. In this study, we introduce a novel approach using the [Mo8S8O8(OH)8(guest)]2− complex, formed by the self‐condensation of four [MoV2O2S2]2− fragments around a guest unit (MoVIO6H4 or oxalate), as a chaotropic scaffold for crystallizing hybrid organic‐inorganic systems with natural cyclodextrins. Our findings reveal that β‐cyclodextrin (β‐CD) facilitates the formation of host‐guest complexes, while α‐cyclodextrin (α‐CD) induces the formation of a Kagome‐type structure with significant voids. These new compounds were thoroughly characterized using X‐ray diffraction (both powder and single‐crystal), N2 adsorption, elemental and thermogravimetric analysis. Additionally, solution studies using 1H NMR titration and small‐angle X‐ray scattering (SAXS) demonstrated pre‐association of the building units in solution. These results enhance our understanding of the design principles for supramolecular structures composed of inorganic polyanions and cyclodextrins. [ABSTRACT FROM AUTHOR]

The iron‐armored chain horse is a military strategy in ancient China to enhance the combat force of the entire army, especially when individual fighters are vulnerable to being picked off one by one. Herein, this strategy is adopted to generate highly efficient metal‐free blue room temperature phosphorescence (RTP) using the world's largest production of dicarboxylate acid. By encapsulating the commercially available chemical disodium terephthalate (DTPA) within the iron armor of α‐cyclodextrin (α‐CD), and subsequently linking the iron‐armored DTPA@α‐CD horses into a crystalline array mediated by hydrogen bonds and Na+ coordination, a highly confined and segregated arrangement of DTPA is achieved, leading to heavy atom‐free deep‐blue phosphorescence with a maximum efficiency of 83.3%. Since the crystalline array of the iron‐armored chain horse DTPA@α‐CD can be facilely obtained through water evaporation, the current phosphorescent material allows for rapid, high‐throughput solution processing of deep‐blue afterglow display, offering an economic and environmentally benign approach for deep‐blue RTP materials and facilitating their application. [ABSTRACT FROM AUTHOR]

Folic acid (FA) and its structural analog, anticancer medicine methotrexate (MTX), are known to form host/guest complexes with native cyclodextrins, of which the most stable are formed with the medium-sized β-cyclodextrin. Based on our research, proving that simple sugars (D-glucose, D-galactose, and D-mannose) can form adducts with folic acid, we envisioned that combining these two types of molecular receptors (cyclodextrin and simple carbohydrates) into one may be beneficial for the complexation of FA and MTX. We designed and obtained host/guest inclusion complexes of FA and MTX with two monoderivatives of β-cyclodextrin—substituted at position 6 with monosaccharide (glucose, G-β-CD) and disaccharide (maltose, Ma-β-CD). The complexation was proved by experimental (NMR, UV-vis, IR, TG, DSC) and theoretical methods. We proved that derivatization of β-cyclodextrin with glucose and maltose has a significant impact on the complexation with FA and MTX, as the addition of one glucose subunit to the structure of the receptor significantly increases the value of association constant for both FA/G-β-CD and MTX/G-β-CD, while further extending a pendant chain (incorporation of maltose subunit) results in no additional changes. [ABSTRACT FROM AUTHOR]

KLEPTOSE® CRYSMEB methylated cyclodextrin derivative displays less methylated group substitution than randomly methylated cyclodextrin. It has demonstrated an impact on atherosclerosis and neurological diseases, linked in part to cholesterol complexation and immune response, however, its impact on inflammatory cascade pathways is not clear. Thus, the impact of KLEPTOSE® CRYSMEB on various pharmacological targets was assessed using human umbilical vein endothelial cells under physiological and inflammatory conditions, followed by screening against twelve human primary cell-based systems designed to model complex human tissue and disease biology of the vasculature, skin, lung, and inflammatory tissues using the BioMAP® Diversity PLUS® panel. Finally, its anti-inflammatory mechanism was investigated on peripheral blood mononuclear cells to evaluate anti-inflammatory or pro-resolving properties. The results showed that KLEPTOSE® CRYSMEB can modulate the immune system in vitro and potentially manage vascular issues by stimulating the expression of molecules involved in the crosstalk between immune cells and other cell types. It showed anti-inflammatory effects that were driven by the inhibition of pro-inflammatory cytokine secretion and could have different impacts on different tissue types. Moreover, this cyclodextrin showed no clear impact on pro-resolving lipid mediators. Additionally, it appeared that the mechanism of action of KLEPTOSE® CRYSMEB seems to not be shared by other well-known anti-inflammatory molecules. Finally, KLEPTOSE® CRYSMEB may have an anti-inflammatory impact, which could be due to its effect on receptors such as TLR or direct complexation with LPS or PGE2, and conversely, this methylated cyclodextrin could stimulate a pro-inflammatory response involving lipid mediators and on proteins involved in communication with immune cells, probably via interaction with membrane cholesterol. [ABSTRACT FROM AUTHOR]

Anemia is a global health problem that affects both adults and children, but treatment is hampered by serious side effects, primarily associated with the gastrointestinal tract with oral administration of drugs. In this study, we aimed to develop an oral form of iron compounds using polymethylsilsesquioxane hydrogels. To boost loading efficiency and prolong release, the iron compounds (FeCl3 and ferrous D-Gluconate) are incorporated into a guest–host complex with 2-hydroxypropyl-beta-cyclodextrin. We used PRXD, SEM, EDX mapping, and FTIR to investigate the complex formation, as well as the incorporation of such complexes into hydrogels. The optimal system underlines a combination of ferrous D-Gluconate and HPCD in a 1:1 molar ratio, embedded into a hydrogel with a modest quantity of silicate crosslinks. We demonstrated the slowing of iron release in a gastric media. Mathematical investigation revealed that the Higuchi mechanism releases iron from the hydrogel. [ABSTRACT FROM AUTHOR]

Inclusion compounds of diclofenac sodium, a non-steroidal anti-inflammatory drug, with native α-, β- and γ-cyclodextrins at varying levels of hydration were prepared by co-grinding in a ball mill. Using TG/DSC analysis, powder X-ray diffraction and solid-state IR spectroscopy, it was shown that when equimolar mixtures of native cyclodextrin and diclofenac are milled, complete inclusion of this pharmaceutical ingredient occurs, regardless of cyclodextrin hydration. The absence of water-guest competition in the solid-state inclusion process is explained by high affinity of diclofenac sodium to cyclodextrins. The prepared complexes have a significantly lower thermal stability than the separate native cyclodextrins and diclofenac sodium. [ABSTRACT FROM AUTHOR]

Affinity-mediated drug delivery utilizes electrostatic, hydrophobic, or other noncovalent interactions between molecules and a polymer to extend the timeframe of drug release. Cyclodextrin polymers exhibit affinity interaction, however, experimentally testing drug candidates for affinity is time-consuming, making computational predictions more effective. One option, docking programs, provide predictions of affinity, but lack reliability, as their accuracy with cyclodextrin remains unverified experimentally. Alternatively, quantitative structure-activity relationship models (QSARs), which analyze statistical relationships between molecular properties, appear more promising. Previously constructed QSARs for cyclodextrin are not publicly available, necessitating an openly accessible model. Around 600 experimental affinities between cyclodextrin and guest molecules were cleaned and imported from published research. The software PaDEL-Descriptor calculated over 1,000 chemical descriptors for each molecule, which were then analyzed with R to create several QSARs with different statistical methods. These QSARs proved highly time efficient, calculating in minutes what docking programs could accomplish in hours. Additionally, on test sets, QSARs reached R2 values of around 0.7--0.8. The speed, accuracy, and accessibility of these QSARs improve evaluation of individual drugs and facilitate screening of large datasets for potential candidates in cyclodextrin affinity-based delivery systems. An app was built to rapidly access model predictions for end users using the Shiny library. To demonstrate the usability for drug release planning, the QSAR predictions were coupled with a mechanistic model of diffusion within the app. Integrating new modules should provide an accessible approach to use other cheminformatic tools in the field of drug delivery. [ABSTRACT FROM AUTHOR]

The diversity of cyclodextrins and their derivatives is increasing with continuous research. In addition to monomolecular cyclodextrins with different branched chains, cyclodextrin-based polymers have emerged. The aim of this review is to summarize these innovations, with a special focus on the study of applications of cyclodextrins and their derivatives in nano-delivery systems. The areas covered include nanospheres, nano-sponges, nanogels, cyclodextrin metal–organic frameworks, liposomes, and emulsions, providing a comprehensive and in-depth understanding of the design and development of nano-delivery systems. [ABSTRACT FROM AUTHOR]

BACKGROUND: Allergic conjunctivitis is one of the most common eye disorders. Different drugs are used for its treatment. Hesperidin is an active substance isolated from Citrus sinensis L. (Rutaceae) fruit peels, with known anti‐inflammatory activity but low solubility. It was complexed with cyclodextrin and encapsulated in situ gel to extend its duration in the eye. RESULTS: The optimized formulation comprised 1% hesperidin, 1.5% hydroxyethyl cellulose, and 16% poloxamer 407. The viscosity at 25 °C was 492 ± 82 cP, and at 35 °C it was 8875 ± 248 cP, the pH was 7.01 ± 0.03, gelation temperature was 34 ± 1.3 °C, and gelation time was 33 ± 1.2 s. There was a 66% in vitro release in the initial 2 h, with a burst effect. A lipoxygenase (LOX) inhibition test determined that hesperidin was active at high doses on leukotyrens seen in the body in allergic diseases. In cell‐culture studies, the hesperidin cyclodextrin complex loaded in situ gel, BRN9‐CD (poloxamer 16%, hydroxy ethyl cellulose (HEC) 1.5%), enhanced cell viability in comparison with the hesperidin solution. It was determined that BRN9‐CD did not cause any irritation in the ocular tissues in the Draize test. CONCLUSION: The findings of this study demonstrate the potential of the in situ gel formulation of hesperidin in terms of ease of application and residence time on the ocular surface. Due to its notable LOX inhibition activity and positive outcomes in the in vivo Draize test, it appears promising for incorporation into pharmaceutical formulations. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Traditional separation membranes used for dye removal often suffer from a trade-off between separation efficiency and water permeability. Herein, we propose a facile approach to prepare cyclodextrin-based high-flux nanofiber membranes by electrospinning and vapor-driven crosslinking processes. The application of glutaraldehyde vapor for crosslinking hydroxypropyl-β-cyclodextrin (HP-β-CD)/polyvinyl alcohol (PVA)/laponite electrospun membranes can build interconnected structures and lead to the formation of a porous hierarchical layer. In addition, the incorporation of inorganic salt, laponite, can alter the crosslinking process, resulting in membranes with improved hydrophilicity and highly maintained electrospun nanofibrous morphology, which contributes to an ultrafast water flux of 1.0 × 105 Lh−1m−2bar−1. Due to the synergetic effect of strong host–guest interaction and electrostatic interaction, the membranes exhibit suitable rejection toward anionic dyes with a high removal efficiency of >99% within a short time and achieve accurate separation for cationic against anionic dyes, accompanied by suitable recyclability with >97% separation efficiency after at least four separation–regenerations. The prepared membranes with remarkable separation efficiency and ultrafast permeation properties might be a promising candidate for high-performance membranes in water treatment. [ABSTRACT FROM AUTHOR]

This study investigates the optimization of submerged culture conditions for the production of extracellular cyclodextrin glucanotransferase (CGTase) enzyme by Bacillus macerans ATCC 8244, employing Taguchi orthogonal array (OA) experimental design methodology. Five critical factors - starch, peptone, temperature, pH, and agitation speed - were examined at two levels using an OA layout of L8 for the experimental design. Analysis revealed a significant enhancement in CGTase yield, with the modified culture conditions resulting in a 21.2% increase from 513.416 U/ml to 622.5 U/ml. The successful application of Taguchi's design methodology underscores its efficacy in optimizing enzyme production processes. This study highlights Taguchi's design potential as a valuable tool for improving CGTase production efficiency while minimizing resource consumption. Additionally, the utilization of a packed bed bioreactor (PBR) facilitated continuous production of β-cyclodextrin (β-CD), demonstrating stability over 10 days with only a slight decrease in productivity. The K m,app value was determined to be 23.4 mg starch/ml, indicating a slight increase. [Display omitted] • Taguchi design optimizes enzyme production and Enhanced CGTase yield by 21.2%. • PBR enables continuous β-CD production and Thermal stability observed over 10 days. • The K m,app value was determined to be 23.4 mg starch/ml. [ABSTRACT FROM AUTHOR]

[Display omitted] • The designed supramolecular colloidal carrier system can efficiently complex and stabilize indocyanine green (ICG). • ICG in carrier showed stable absorption and fluorescence in NIR range. • ICG in carrier specifically targeted tumor cells observed under NIR endoscopic imaging. • ICG in carrier enhanced permeation and accumulation in 3D tumor spheroids. Indocyanine green (ICG) is an FDA-approved medical diagnostic agent that is widely used as a near-infrared (NIR) fluorescent imaging molecular probe. However, ICG tends to aggregate to form dimers or H-aggregates in water and lacks physical and optical stability, which greatly decreases its absorbance and fluorescence intensity in various applications. Additionally, ICG has no tissue- or tumor-targeting properties, and its structure is not easy to modify, which has further limited its application in cancer diagnosis. In this study, we addressed these challenges by developing a supramolecular colloidal carrier system that targets tumor cells. To this end, we synthesized a water-soluble β-cyclodextrin (β-CD) polymer conjugated with folate (FA), denoted PCD-FA, which is capable of forming inclusion complexes with ICG in water through host–guest interactions between the β-CD moieties and ICG molecules. The inclusion complexes formed by PCD-FA and ICG, called ICG@PCD-FA, dispersed stably in solution as colloidal nanoparticles, greatly improving the physical and optical properties of ICG by preventing ICG dimer formation, where ICG appeared as monomers and even J-aggregates. This resulted in stronger and more stable absorption at a longer wavelength of 900 nm, which may allow for deeper tissue penetration and imaging with reduced interference from biological tissues' autofluorescence. Moreover, ICG@PCD-FA showed a targeting effect on folate receptor-positive (FR+) tumor cells, which specifically highlighted FR+ cells via NIR endoscopic imaging. Notably, ICG@PCD-FA further improved permeation and accumulation in FR+ 3D tumor spheroids. Therefore, this ICG@PCD-FA supramolecular colloidal system may have a great potential for use in tumor NIR imaging and diagnostic applications. [ABSTRACT FROM AUTHOR]

With the rapid expansion of the scale of nuclear energy, the proper treatment of radioactive waste generated by the nuclear industry has become one of the most important issues for the further development of nuclear energy. Cyclodextrin, as a kind of cyclic oligosaccharide composed of several glucopyranose units, has a good prospect of application in the field of radioactive ions adsorption and separation, because of its special molecular structure of internal hydrophobicity and external hydrophilicity. However, due to the presence of a large number of hydroxyl groups in the cyclodextrin molecules, they are easily soluble in water. Generally, the solidification of cyclodextrins to insoluble solids is always needed before being used as adsorption materials. Depending on the different methods of " solidification", cyclodextrin based adsorbent materials can be divided into three types: loaded cyclodextrin materials, cyclodextrin polymer materials, and cyclodextrin inclusion complex materials. The synthesis and application research advances of the three types of cyclodextrin adsorbent materials in radioactive ion adsorption and separation are summarized, the related adsorption mechanisms are discussed. Besides, the perspectives of the cyclodextrin based adsorbents in the field of radioactive ion adsorption are presented. [ABSTRACT FROM AUTHOR]

In this study, a synthetic approach is reported for generating hepta-branched β-cyclodextrins (CDs) bearing heterogeneous carbohydrate residues at their primary side via a one-pot process with a simultaneous click chemistry reaction. The reactions were performed by reacting two or three different species of 2-propynylated glycosides with a hepta-azide functional β-CD at various reaction molar ratios. 2-Propynylated glycosides acted as heterogeneous carbohydrate sources embedded into a hepta-azide functional β-CD. The simultaneous click chemistry reactions generated several desired β-CD derivatives with varying densities of the heterogeneous carbohydrates in a one-pot process. The article describes the effects of the combination of 2-propynylated glycosides and the reaction molar ratios in the click chemistry reactions. [ABSTRACT FROM AUTHOR]

AbstractAcute sun exposure could lead to erythema and inflammation. This Investigation aims to determine the efficacy of the complexation of peppermint oil (PO) with cyclodextrin in enhancing its physicochemical properties. Nano-organogels were prepared by direct hot melting method. Cyclodextrin (CD) PO was prepared by co-lyophilized method and included in F6. The particle size values were all below 150 nm. F6 polymeric showed high antioxidant activity, in vitro SPF, and stability. CD nano-organogel showed the least release and the highest skin deposition values. This high skin deposition is assured by confocal microscopy. Histology revealed its anti-inflammatory effect against acute UV irradiation. PO CD nano-organogel demonstrates a promising modality for anti-inflammatory therapy against UV irradiation. [ABSTRACT FROM AUTHOR]

Tyramine (TRM) is a biogenic catecholamine neurotransmitter, which can trigger migraines and hypertension. TRM accumulated in foods is reduced and detected using additive cyclodextrins (CDs) while their association characteristics remain unclear. Here, single-crystal X-ray diffraction and density functional theory (DFT) calculation have been performed, demonstrating the elusive pseudopolymorphs in β-CD inclusion complexes with TRM base/HCl, β-CD·0.5TRM·7.6H2O (1) and β-CD·TRM HCl·4H2O (2) and the rare α-CD·0.5(TRM HCl)·10H2O (3) exclusion complex. Both 1 and 2 share the common inclusion mode with similar TRM structures in the round and elliptical β-CD cavities, belong to the monoclinic space group P21, and have similar herringbone packing structures. Furthermore, 3 differs from 2, as the smaller twofold symmetry-related, round α-CD prefers an exclusion complex with the twofold disordered TRM–H+ sites. In the orthorhombic P21212 lattice, α-CDs are packed in a channel-type structure, where the column-like cavity is occupied by disordered water sites. DFT results indicate that β-CD remains elliptical to suitably accommodate TRM, yielding an energetically favorable inclusion complex, which is significantly contributed by the β-CD deformation, and the inclusion complex of α-CD with the TRM aminoethyl side chain is also energetically favorable compared to the exclusion mode. This study suggests the CD implications for food safety and drug/bioactive formulation and delivery. [ABSTRACT FROM AUTHOR]

There is an urgent need to develop safer and more effective modalities for the treatment of numerous pathologies due to the increasing rates of drug resistance, undesired side effects, poor clinical outcomes, etc. Over the past decades, cyclodextrins (CDs) have gathered great attention as potential drug carriers due to their ability to enhance their bioactivities and properties. Likewise, selenium (Se) and tellurium (Te) have been extensively studied during the last decades due to their possible therapeutical applications. Although there is limited research on the relationship between Se and Te and CDs, herein, we highlight different representative examples of the advances related to this topic as well as give our view on the future directions of this emerging area of research. This review encompasses three different aspects of this relationship: (1) modification of the structure of the different CDs; (2) formation of host–guest interaction complexes of naïve CDs with Se and Te derivatives in order to overcome specific limitations of the latter; and (3) the use of CDs as catalysts to achieve novel Se and Te compounds. [ABSTRACT FROM AUTHOR]

Background: Curcumin is a compound that occurs in the rhizomes of the turmeric plant (Curcuma longa) and has shown potential for the treatment of illnesses including certain neurodegenerative diseases. The bioavailability of curcumin is hindered by its extremely poor aqueous solubility. Results: This study aimed to apply formulation strategies such as inclusion complex formation with hydroxypropyl-β-cyclodextrin (HPβCD), as well as amorphous solid dispersion (ASD) formation with poly(vinylpyrrolidone-co-vinyl acetate) (PVP VA64) and hydroxypropyl methylcellulose (HPMC) to increase curcumin's solubility and thereby its nasal epithelial membrane permeation. The curcumin formulations were evaluated by means of DSC, TGA, FT-IR, XRPD, microscopic imaging, aqueous solubility and membrane permeation across nasal respiratory and olfactory epithelial membranes. The solubility of curcumin was substantially increased by the formulations from 8.4 µg/ml for the curcumin raw material to 79.0 µg/ml for the HPβCD inclusion complex, 256.4 µg/ml for the HPMC ASD and 314.9 µg/ml for the PVP VA64 ASD. The HPMC ASD only slightly changed the membrane permeation of curcumin, while the PVP VA64 ASD decreased the membrane permeation of curcumin. The HPβCD inclusion complex enhanced the nasal epithelial membrane permeation of curcumin statistically significantly across the olfactory epithelial tissue and extensively across the respiratory epithelial tissue. Conclusion: Complexation of curcumin with HPβCD enhanced the solubility of curcumin and thereby also increased its permeation across excised nasal respiratory and olfactory epithelial tissue. This indicated high potential of the curcumin-HPβCD complex for nose-to-brain delivery of curcumin for treatment of neurodegenerative diseases by means of intranasal administration. [ABSTRACT FROM AUTHOR]

Phosphorothioate (PS) oligonucleotides have drawn more and more attention lately due to their great therapeutic potential. The presence of one (or several) phosphorothioate moiety (ies) improves pharmacokinetic properties but at the same time creates an additional chiral center for each phosphorothioate linkage, and thus diastereomers. It is therefore important to develop analytical strategies to monitor individual species to enable more in-depth investigations. In this study, a PVA coated capillary with a background electrolyte made of 100 mM phosphoric acid adjusted to pH 3.0 with triethanolamine was used. A design of experimental approach provides the optimal conditions for the separation of the eight isobaric diastereomers bearing one phosphorothioate linkage (Mix 1), and the separation of the 12 isobaric diastereomers of a mixture made of oligonucleotides with two phosphorothioate linkages (Mix 2). Remarkably, full separation in Mix 1 could be achieved using a combination of a cationic cyclodextrin (2-hydroxy-3-N,N,N-trimethylamino) propyl-γ-CD chloride, and an anionic cyclodextrin (carboxymethyl-β-cyclodextrin sodium salt), while a second cationic cyclodextrin (2-hydroxy-3-N,N,N-trimethylamino) propyl- β-CD chloride) was required for Mix 2, providing additional selectivity. [ABSTRACT FROM AUTHOR]

Precision‐engineered light‐triggered hydrogels are important for a diversity of applications. However, fields such as biomaterials require wavelength outside the harsh UV regime to prevent photodamage, typically requiring chromophores with extended π‐conjugation that suffer from poor water solubility. Herein, we demonstrate how cyclodextrins can be used as auxiliary agents to not only solubilize such chromophores, but even to preorganize them in a 2 : 2 host‐guest inclusion complex to facilitate photodimerization. We apply our concept to styrylpyrene‐end‐functionalized star‐shaped polyethylene glycols (sPEGs). We initially unravel details of the host‐guest inclusion complex using spectroscopy and mass spectrometry to give clear evidence of a 2 : 2 complex formation. Subsequently, we show that the resultant supramolecularly linked hydrogels conform to theories of supramolecular quasi‐ideal model networks, and derive details on their association dynamics using in‐depth rheological measurements and kinetic models. By comparing sPEGs of different arm length, we further elucidate the model network topology and the accessible mechanical property space. The photo‐mediated dimerization proceeds smoothly, allowing to transform the supramolecular model networks into covalent ones. We submit that our strategy opens avenues for executing hydrophobic photochemistry in aqueous environments with enhanced control over reactivity, hydrogel topology or programmable mechanical properties. [ABSTRACT FROM AUTHOR]

This study aimed to extract apigenin and luteolin from celery seeds using 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) based ultrasonic-assisted technique. Optimal extraction conditions were determined through the integration of support vector regression combined with various optimization algorithms, including Genetic Algorithm, Particle Swarm Optimization, Gray Wolf Optimizer, Bat Algorithm, Firefly Algorithm, and Cuckoo Search Algorithm. The identified optimal conditions included an extraction time of 52 min, an HP-β-CD concentration of 24 mg/mL, and a solvent-to-solid ratio of 24 mL/g. Under these conditions, the predicted apigenin and luteolin content in the extract were 0.156 and 0.814 mg/g, respectively, closely aligning with the actual values of 0.158 ± 0.005 mg/g and 0.807 ± 0.008 mg/g. Notably, the HP-β-CD/water extract exhibited significantly higher concentrations of active ingredients and antioxidant activity compared to the water extract, with the content of apigenin and luteolin in the water extract being only 25 and 45%, respectively, compared to the HP-β-CD/water extract. Regarding the antioxidant effect, the water extract displayed a 50% scavenging capacity (SC50) of 331.29 ± 20.5 g/mL, whereas the SC50 for the HP-β-CD/water extract was 89.04 ± 4.70 g/mL. Molecular modeling and IR spectra analysis also suggested the formation of inclusion complexes between HP-β-CD and apigenin/luteolin. These findings suggested that HP-β-CD could be a preferable alternative to conventional solvents due to its advantages, such as easier control, safety, and cost-effectiveness. In addition, the use of support vector regression and nature-inspired optimization algorithms could be promising alternatives to traditional response surface methodology. [ABSTRACT FROM AUTHOR]

Cyclodextrins (CDs) are cyclic oligosaccharides able to form noncovalent water-soluble complexes useful in many different applications for the solubilization, delivery, and greater bioavailability of hydrophobic drugs. The complexation of 5-fluorouracil (5-FU) with natural or synthetic cyclodextrins permits the solubilization of this poorly soluble anticancer drug. In this theoretical work, the complexes between β-CD and 5-FU are investigated using molecular mechanics (MM) and molecular dynamics (MD) simulations in water. The inclusion complexes are formed thanks to the favorable intermolecular interactions between β-CD and 5-FU. Both 1:1 and 1:2 β-CD/5-FU stoichiometries are investigated, providing insight into their interaction geometries and stability over time in water. In the 1:2 β-CD/5-FU complexes, the intermolecular interactions affect the drug's mobility, suggesting a two-step release mechanism: a fast release for the more exposed and hydrated drug molecule, with greater freedom of movement near the β-CD rims, and a slow one for the less-hydrated and well-encapsulated and confined drug. MD simulations study the intermolecular interactions between drugs and specific carriers at the atomistic level, suggesting a possible release mechanism and highlighting the role of the impact of the drug concentration on the kinetics process in water. A comparison with experimental data in the literature provides further insights. [ABSTRACT FROM AUTHOR]

The basic hydrolysis of Malachite Green (MG) in the presence of β-Cyclodextrin (β-CD) has been studied using UV-Vis spectroscopic techniques and at 20 °C. β-CD was found to catalyze the basic hydrolysis. Indeed, this basic hydrolysis is catalyzed by the interaction cyclodextrin hydroxyl group, in its deprotonated form with the carbocation in the host-guest complex. The proposed model has been successfully applied to a reaction catalyzed by CD. It considers two simultaneous pathways in the aqueous medium involving free hydroxyl ions and the substrate-CD complex. The model allows us to obtain the kinetic parameters including the bimolecular rate constant between MG and HO− in bulk water (kw = 1.47 ± 0.01 mol−1s−1), the rate constant between MG and the deprotonated hydroxyl group of β-CD inside the host-guest complex (kCD = 0.25 ± 0.03 s−1) and the binding constant of MG inside the β-CD (KS = 2500 ± 50). This behavior is like the hydrolysis of Cristal Violet (CV) in the same reaction media. [ABSTRACT FROM AUTHOR]

Numerous strategies exist to design a suitable bone graft made from polyurethane (PU) nanofibers. However, using PU nanofibers is impractical owing to their hydrophobicity. This work transforms the hydrophobicity of PU nanofibers using β‐cyclodextrin (β‐CD) and zinc oxide (ZnO) nanoparticles (NPs). Transmission and scanning electron microscopy (SEM) indicated the size of ~100 to 200 nm for ZnO NPs, and these NPs could finely harmonize inside nanofibers. The phenolphthalein absorbance test confirmed the inclusion of ZnO and β‐CD. Fourier transform infrared, X‐ray diffraction, and photoelectron spectroscopy showed that synthesized composites have intermolecular hydrogen interactions between the PU, β‐CD, and ZnO NPs. These embellishments improved the hydrophilicity from a contact angle of 60.2 ± 0.2° to 0°. The tensile strength of modified fibers increased from 2.16 ± 0.14 to 6.65 ± 6.0 MPa. The incorporation of ZnO NPs caused the mineralization of the nanofibers and the maximum number of hydroxyapatite NPs in the composite, which had the highest concentration of ZnO NPs. These nanofiber mats boosted the proliferation of Human Embryonic Kidney 293 T cells till 6 days of culture for the nanofiber with 5% β‐CD and 75 mg ZnO NPs combination. Cell fixation studies indicated the successful attachment of cells onto nanofibers. Consequently, our multifunctional scaffolds could be osteoproductive and osteoinductive biomaterials for future bone tissue engineering. [ABSTRACT FROM AUTHOR]

In this study, it was intended to enhance the water and oil repellency properties of TencelTM fibres that are in naturally hydrophilic character to expand their usage possibilities. For this aim, Tencel™ fabrics were treated by floroalkyloligosiloxan (Dynasylan F 8815), cyclodextrin, crosslinking agent and catalyst. By preparing seven different treatment recipes, fabric application processes were carried out in one or in two stages. Then, the properties of the samples like water and oil repellency values, durability of the treatments after washing, bursting strength, stiffness and yellowness were determined and compared. Moreover, the microscopic images of the samples were evaluated and chemical structure of the fabric surfaces were characterized. The most withstanding outcome was obtained by the two stages application of floroalkyloligosiloxan, cyclodextrin, crosslinking agent and catalyst altogether to Tencel™ fabric surfaces. [ABSTRACT FROM AUTHOR]

Silver-cobalt nanoparticles were synthesised using a chemical reduction technique. Olanzapine-cyclodextrin inclusion complex containing Ag and Ag/Co nanoparticles was examined using UV-Visible, fluorescence, computational method, FT-IR, differential scanning colorimeter, X-RD, FE-SEM, and TEM methods. A blue-shifted absorption maximum was seen in the presence of the OP/CD inclusion complex with silver and silver/cobalt nanoparticles. Multiple emission was noted in the α-CD and β-CD. TEM images conformed the formation of nanorods in Ag/OP/CD and Ag/Co/OP/CD. The pure isolated OP drug or Ag/OP/CD and Ag/Co/OP/CD do not exhibit any antibacterial activity. [ABSTRACT FROM AUTHOR]

Among different substance classes, New Psychoactive Substances (NPS) comprise chiral amphetamines for stimulant and empathic effects. There is little knowledge in terms of clinical studies about possibly different effects of the two enantiomers of novel amphetamine derivatives. For this reason, there is a big demand for enantioseparation method development of this new substance class. Regarding gas chromatography, cyclodextrins proved to be effective for enantioseparation of NPS. In our attempt, an Astec® Chiraldex™ G‐PN column containing 2,6‐di‐O‐pentyl‐3‐propionyl‐γ‐cyclodextrin and a Lipodex™ D column containing heptakis‐(2,6‐di‐O‐pentyl‐O‐acetyl)‐β‐cyclodextrin as chiral selector served as stationary phases in a Shimadzu GCMS‐QP2010 SE system. Because of the special coating, maximum temperature is limited to 200 °C isothermal or 220 °C in programmed mode. To ensure detection, trifluoroacetic anhydride (TFAA) was used to increase sample volatility.1 As a result, 35 amphetamines were tested as their TFAA‐derivatives. A screening method with a temperature gradient from 140 °C to 200 °C at a heating ramp of 1 °C per minute and final time of 5 min, showed baseline separation for seven and partial separations for 16 trifluoro acetylated amphetamines using the Chiraldex™ G‐PN column. Six baseline and nine partial separations were observed with the Lipodex™ D column, respectively. [ABSTRACT FROM AUTHOR]

Vinblastine was investigated in the presence of cyclodextrin derivatives on different cancer cells and it was established that the anticancer activity was unchanged. This was the first step of a long procedure resulting in the dosage of vinblastine together with cyclodextrin or its derivatives to improve the adverse effects. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (AuNPs) are good candidates for donor material in energy transfer systems and can easily be functionalized with various ligands on the surface with Au–S bonding. Cyclodextrin (CD) forms inclusion complexes with fluorophores due to its unique structure for host–guest interaction. In this study, we fabricated βCD-functionalized AuNPs using different lengths of thiol ligands and recognized cholesterol to confirm the energy-transfer-based turn-on fluorescence mechanism. AuNP–βCD conjugated with various thiol ligands and quenched the fluorescein (Fl) dye, forming βCD-Fl inclusion complexes. As the distance between AuNPs and βCD decreased, the quenching efficiency became higher. The quenched fluorescence was recovered when the cholesterol replaced the Fl because of the stronger binding affinity of the cholesterol with βCD. The efficiency of cholesterol recognition was also affected by the energy transfer effect because the shorter βCD ligand had a higher fluorescence recovery. Furthermore, we fabricated a liposome with cholesterol embedded in the lipid bilayer membrane to mimic the cholesterol coexisting with lipids in human serum. These cellular cholesterols accelerated the replacement of the Fl molecules, resulting in a fluorescence recovery higher than that of pure lipid. These discoveries are expected to give guidance towards cholesterol sensors or energy-transfer-based biosensors using AuNPs. [ABSTRACT FROM AUTHOR]

Summary: Objective: This study sought to systematically compare the efficacy and mechanism of cyclodextrins as drug interventions in lipid metabolism diseases, potentially providing ideas for subsequent research directions and clinical applications. Methods: We used the bibliometric method for feature mining, applied VOSviewer software for clustering analysis, and applied content analysis for objective descriptions and accurate analysis. Results: (1) We collected more than 50 studies, which is the basic database of this study. (2) The academic bubble map showed that this research area was popular in the United States. (3) Cluster analysis showed that the intensively studied diseases in this field were Niemann–Pick type C (NPC), atherosclerosis (AS), and obesity. The hot‐spot cyclodextrin types were HP‐β‐CD. (4) Literature measurement revealed the involvement of 15 types of lipid metabolism diseases. Among them, NPC, diabetes, and obesity were studied in clinical trials. Dyslipidemia and AS have been reported relatively more frequently in animal experiments. The studies of cellular experiments provide insight into the molecular mechanisms that intervene in lipid metabolism diseases from multiple perspectives. The exploration of the molecular mechanisms by which cyclodextrins exert their pharmacological effects mainly revolves around lipid metabolism. Conclusion: It is worthwhile to investigate the role and mechanism of cyclodextrins in other lipid metabolism diseases. The potential efficacy evaluation of cyclodextrins as pharmaceutical drugs for oral or injectable formulations is less studied and may become a new focus in the future. [ABSTRACT FROM AUTHOR]

Type 2 diabetes mellitus is a metabolic dreadful disease caused by an uncontrolled glucose level in the bloodstream, particularly high after a meal. Inhibitors of glucosidases, involved in the digestion of carbohydrates, can regulate this post‐prandial increase in glucose concentration. The traditional drugs act as competitive inhibitors of both pancreatic α‐amylase and α‐glucosidases and this unselective inhibition is behind severe gastrointestinal side effects related to the concomitant inhibition of α‐amylase. We described herein some perglycosylated cyclodextrins as efficient and selective inhibitors of α‐glucosidase with low micromolar IC50 (3.64‐7.98 μM) compared to the acarbose (IC50 212 μM), clinically used for patients suffering from type 2 diabetes. On the other hand, they do not inhibit α‐amylase (IC50>500 μM). Structure/activity relationship rationalization suggests multiple interactions between the described inhibitors and α‐glucosidase, which support the existence of both active site and allosteric interactions. [ABSTRACT FROM AUTHOR]

The ability of β-CD to form inclusion complexes with ibuprofen (IBU) and at the same time to make a two-phase system with citric acid was explored in the present study for achieving improved solubility and dissolution rate of IBU. Mechanical milling as well as mechanical milling combined with thermal annealing of the powder mixtures were applied as synthetic methods. Solubility and dissolution kinetics of the complexes were studied in compliance with European Pharmacopoeia (ICH Q4B). β-CD and citric acid (CA) molecules were shown to interact by both ball milling (BM), thermal annealing, as well as BM with subsequent annealing. Complexes were also formed by milling the three compounds (β-CD, CA and IBU) simultaneously, as well as by a consecutive first including IBU into β-CD and then binding the formed β-CD/IBU inclusion complex with CA. As a result, ternary β-CD/IBU/CA complex formed by initial incorporation of ibuprofen into β-CD, followed by successive formation of a two-phase mixture with CA, exhibited notably improved dissolution kinetics compared to the pure ibuprofen and slightly better compared to the binary β-CD/IBU system. Although the addition of CA to β-CD/IBU does not significantly increase the solubility rate of IBU, it must be considered that the amount of β-CD is significantly less in the ternary complex compared to the binary β-CD/IBU. [ABSTRACT FROM AUTHOR]

Our modern study is going to inspect new inclusion phenomena between the 1-butyl-2,3-dimethylimidazolium tetrafluoroborate [Bdmim]BF4 ionic liquid (IL) and the host α-Cyclodextrin (α-CD) by a 1:1 ratio and newly formed inclusion complex was further explored by the 1H-NMR, FT-IR, UV–vis spectroscopy, PXRD, DSC, and SEM analysis. Molecular docking was also performed to investigate the encapsulation of the inclusion complex in which orientation and it have been seen that the IL [Bdmim]BF4 enters into the α-CD cavity with a 1:1 ratio was further established with the help of Job's plot. Furthermore, the antibacterial activity of [Bdmim]BF4 IL and its inclusion complex was verified against some Gram-positive and Gram-negative bacterial strains. [ABSTRACT FROM AUTHOR]

The development of environment‐friendly bacteriostats in humid atmosphere is designated as a crucial step pointing to sustainable antibiotic‐free alterative. Thanks to the excellent biosafety and intrinsic bacteriostatic attributes, bioactive phytochemical formulations become a fascinating substitute for traditional antibiotics; yet, it remains a challenge to deliver them toward moisture‐activated bacteriostatic application due to the unclear release mechanism and bacteriostatic behavior. Benefitting from "green" metal–organic frameworks (MOFs) evolved from natural γ‐cyclodextrin (γ‐CD) and potassium ion (K+), an intelligent moisture‐activated phytochemical formulation is developed, which is featured by grafting bacteriostatic vanillin (a specific phytochemical extracted from Rutaceae vanilla bean) into microporous structure of MOFs via ligand implantation mechanism. According to the molecular simulation docking, the dominant pattern of host–guest structure is characteristic for H‐bond with a length of 1.9 Å, beneficial for the sterling adsorption capacity. Nevertheless, under moisture exposure, the intermolecular H‐bond is disrupted for vanillin release to destroy bacterial membrane structure, accelerate protein decomposition, and especially inhibit virulence gene transcription of cfa gene in Escherichia coli and sea gene in Staphylococcus aureus, directing to upgrade the insights into the bacteriostatic potency of phytochemicals in high‐humidity circumstance. [ABSTRACT FROM AUTHOR]

Cyclodextrin-based nanosponges (CDNSs) are complex macromolecular structures composed of individual cyclodextrins (CDs) and nanochannels created between cross-linked CD units and cross-linkers. Due to their unique structural and physicochemical properties, CDNSs can possess even more beneficial pharmaceutical features than single CDs. In this comprehensive review, various aspects related to CDNSs are summarized. Particular attention was paid to overviewing structural properties, methods of synthesis, and physicochemical analysis of CDNSs using various analytical methods, such as DLS, PXRD, TGA, DSC, FT-IR, NMR, and phase solubility studies. Also, due to the significant role of CDNSs in pharmaceutical research and industry, aspects such as drug loading, drug release studies, and kinetics profile evaluation of drug–CDNS complexes were carefully reviewed. The aim of this paper is to find the relationships between the physicochemical features and to identify crucial characteristics that are influential for using CDNSs as convenient drug delivery systems. [ABSTRACT FROM AUTHOR]

Pain and anesthesia are a problem for all physicians. Scientists from different countries are constantly searching for new anesthetic agents and methods of general anesthesia. In anesthesiology, the role and importance of local anesthesia always remain topical. In the present work, a comparative analysis of the results of pharmacological studies on models of the conduction and terminal anesthesia, as well as acute toxicity studies of the inclusion complex of 1-methyl-4-ethynyl-4-hydroxypiperidine (MEP) with β-cyclodextrin, was carried out. A virtual screening and comparative analysis of pharmacological activity were also performed on a number of the prepared piperidine derivatives and their host–guest complexes of β-cyclodextrin to identify the structure–activity relationship. Various programs were used to study biological activity in silico. For comparative analysis of chemical and pharmacological properties, data from previous works were used. For some piperidine derivatives, new dosage forms were prepared as beta-cyclodextrin host–guest complexes. Some compounds were recognized as promising local anesthetics. Pharmacological studies have shown that KFCD-7 is more active than reference drugs in terms of local anesthetic activity and acute toxicity but is less active than host–guest complexes, based on other piperidines. This fact is in good agreement with the predicted results of biological activity. [ABSTRACT FROM AUTHOR]

Diarylethene derivatives are one of the promising compounds for practical applications including optical memory, display, sensor, and photoactuator. In this work, we newly designed and synthesized an inverse type diarylethene derivative bearing sodium carbonate groups at the p‐position of the lateral phenyl ring and investigated the photochromic behavior in the presence and absence of cyclodextrins (CDs) (αCD, βCD, and γCD). Interestingly, only in the presence of βCD, the photocyclization reactivity decreased. From the results of job‐plots, NOESY spectra, and quantum chemical calculations, it was suggested that the distinctive interaction between the diarylethene and βCD leads to the restriction of molecular geometrical change, resulting in the suppression of the photocyclization reactivity. These results provide information on the rational designing of inverse type diarylethenes with advanced properties. [ABSTRACT FROM AUTHOR]

The emergence and mutation of pathogenic viruses have been occurring at an unprecedented rate in recent decades. The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has developed into a global public health crisis due to extensive viral transmission. In situ RNA mapping has revealed angiotensin-converting enzyme 2 (ACE2) expression to be highest in the nose and lower in the lung, pointing to nasal susceptibility as a predominant route for infection and the cause of subsequent pulmonary effects. By blocking viral attachment and entry at the nasal airway using a cyclodextrin-based formulation, a preventative therapy can be developed to reduce viral infection at the site of entry. Here, we assess the safety and antiviral efficacy of cyclodextrin-based formulations. From these studies, hydroxypropyl beta-cyclodextrin (HPBCD) and hydroxypropyl gamma-cyclodextrin (HPGCD) were then further evaluated for antiviral effects using SARS-CoV-2 pseudotypes. Efficacy findings were confirmed with SARS-CoV-2 Delta variant infection of Calu-3 cells and using a K18-hACE2 murine model. Intranasal pre-treatment with HPBCD-based formulations reduced viral load and inflammatory signaling in the lung. In vitro efficacy studies were further conducted using lentiviruses, murine hepatitis virus (MHV), and influenza A virus subtype H1N1. These findings suggest HPBCD may be used as an agnostic barrier against transmissible pathogens, including but not limited to SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Slightly different reaction conditions afforded two distinct cavity‐shaped cis‐chelating diphosphanes from the same starting materials, namely diphenyl(2‐phosphanylphenyl)phosphane and an α–cyclodextrin‐derived dimesylate. Thanks to their metal‐confining properties, the two diphosphanes form only mononuclear [CuX(PP)] complexes (X=Cl, Br, or I) with the tricoordinated metal ion located just above the center of the cavity. The two series of CuI complexes display markedly different luminescence properties that are both influenced by the electronic properties of the ligand and the unique steric environment provided by the cyclodextrin (CD) cavity. The excited state lifetimes of all complexes are significantly longer than those of the cavity‐free analogues suggesting peculiar electronic effects that affect radiative deactivation constants. The overall picture stemming from absorption and emission data suggests close‐lying charge‐transfer (MLCT, XLCT) and triplet ligand‐centered (LC) excited states. [ABSTRACT FROM AUTHOR]

Commercial cyclodextrins (CDs) are commonly used to form inclusion complexes (ICs) with different molecules in order to enhance their water solubility, stability, and bioavailability. Nowadays, there is strong, convincing evidence of the anticancer effect of selenium (Se)-containing compounds. However, pharmaceutical limitations, such as an unpleasant taste or poor aqueous solubility, impede their further evaluation and clinical use. In this work, we study the enhancement of solubility with CD complexes for a set of different nonsteroidal anti-inflammatory drug (NSAID) derivatives with Se as selenoester or diacyl diselenide chemical forms, with demonstrated antitumoral activity. The CD complexes were analyzed via nuclear magnetic resonance (NMR) spectroscopic techniques. In order to obtain additional data that could help explain the experimental results obtained, 3D models of the theoretical CD-compound complexes were constructed using molecular modeling techniques. Among all the compounds, I.3e and II.5 showed a remarkable increase in their water solubility, which could be ascribed to the formation of the most stable interactions with the CDs used, in agreement with the in silico studies performed. Thus, the preliminary results obtained in this work led us to confirm the selection of β and γ-CD as the most suitable for overcoming the pharmaceutical drawbacks of these Se derivatives. [ABSTRACT FROM AUTHOR]

In order to study the effects of different storage temperatures (4, 25 " and 37 ") on cyclodextrin stabilized Antarctic krill oil Pickering emulsion and determine the shelf life. Firstly, the Antarctic krill oil Pickering emulsion was prepared by high--speed shearing method, and the particle size and potential of the emulsion were 13.64 !m, --38.14 mV, and the centrifugal stability was 85.34%. And then, the effects of different storage temperatures on emulsions were studied by the appearance and microscopic changes of emulsions, particle size, potential, centrifugal stability, cream¬ing index, POV and TBARS. The results indicated that higher temperature resulted in more acute Brownian movement, which increased the possibility of coalescence and the shortened the time required for emulsion instability. The shelf life of the emulsion under 4, 25 " and 37 " was 28, 16 d and 8 d, respectively. This study provides a reference for the development and utilization of Antarctic krill resources. [ABSTRACT FROM AUTHOR]

Background: The global prevalence of vitamin D (VitD) deficiency associated with numerous acute and chronic diseases has led to strategies to improve the VitD status through dietary intake of VitD-fortified foods and VitD supplementation. In this context, the circulating form of VitD3 (cholecalciferol) in the human body, 25-hydroxy-VitD3 (calcifediol, 25OHVitD3), has a much higher efficacy in improving the VitD status, which has motivated researchers to develop methods for its effective and sustainable synthesis. Conventional monooxygenase-/peroxygenase-based biocatalytic platforms for the conversion of VitD3 to value-added 25OHVitD3 are generally limited by a low selectivity and yield, costly reliance on cyclodextrins and electron donor systems, or by the use of toxic co-substrates. Results: In this study, we used a whole-cell approach for biocatalytic 25OHVitD3 synthesis, in which a molybdenum-dependent steroid C25 dehydrogenase was produced in the denitrifying bacterium Thauera aromatica under semi-aerobic conditions, where the activity of the enzyme remained stable. This enzyme uses water as a highly selective VitD3 hydroxylating agent and is independent of an electron donor system. High density suspensions of resting cells producing steroid C25 dehydrogenase catalysed the conversion of VitD3 to 25OHVitD3 using either O2 via the endogenous respiratory chain or externally added ferricyanide as low cost electron acceptor. The maximum 25OHVitD3 titer achieved was 1.85 g L–1 within 50 h with a yield of 99%, which is 2.2 times higher than the highest reported value obtained with previous biocatalytic systems. In addition, we developed a simple method for the recycling of the costly VitD3 solubiliser cyclodextrin, which could be reused for 10 reaction cycles without a significant loss of quality or quantity. Conclusions: The established steroid C25 dehydrogenase-based whole-cell system for the value-adding conversion of VitD3 to 25OHVitD3 offers a number of advantages in comparison to conventional oxygenase-/peroxygenase-based systems including its high selectivity, independence from an electron donor system, and the higher product titer and yield. Together with the established cyclodextrin recycling procedure, the established system provides an attractive platform for large-scale 25OHVitD3 synthesis. [ABSTRACT FROM AUTHOR]

Both cyclodextrin (CD) and porous silica possess interesting properties of adsorption and release. A silica–CD hybrid, therefore, could synergically merge the properties of the two components, giving rise to a material with appealing properties for both environmental and pharmaceutical applications. With this aim, in the present study, a first hybrid is obtained through one-pot sol–gel synthesis starting from CD and tetramethyl orthosilicate (TMOS) as a silica precursor. In particular, methyl-β-cyclodextrin (bMCD) is selected for this purpose. The obtained bMCD–silica hybrid is a dense material containing a considerable amount of bMCD (45 wt.%) in amorphous form and therefore represents a promising support. However, since a high specific surface area is desirable to increase the release/adsorption properties, an attempt is made to produce the hybrid material in the form of an aerogel. Both the synthesis of the gel and its drying in supercritical CO2 are optimized in order to reach this goal. All the obtained samples are characterized in terms of their physico-chemical properties (infra-red spectroscopy, thermogravimetry) and structure (X-ray diffraction, electron microscopy) in order to investigate their composition and the interaction between the organic component (bMCD) and the inorganic one (silica). [ABSTRACT FROM AUTHOR]

The production of hydrothermal carbons from glucose, cyclodextrin, and starch was reported at 180 °C and 200 °C for 24 hr, both with and without 2-chloro propionic acid. The yields of hydrothermal carbons varied depending on the feedstock and temperature. At the lowest temperature, glucose gave the highest yield of hydrochar, while at 200 °C, the yields did not differ significantly among the three feedstocks, with the highest yield obtained for cyclodextrin-derived hydrochars. The use of a catalyst not only decreased the yield of hydrothermal carbons but also resulted in an increase in the diameter of hydrochars for all saccharides. When compared to raw saccharides, the O/C and H/C ratios of hydrothermal carbons were significantly lower, suggesting that significant deoxygenation and dehydration occurred after the HTC processing. In the non-catalytic runs, hydrochars for each feedstock showed an increase in aromatic content when the temperature was increased from 180 °C to 200 °C. The size of the carbon spheres was significantly influenced by various factors including the operating conditions, the type of saccharide used, and the pH of the aqueous solutions. The diameters of carbon spheres produced in runs with catalysts were larger when compared to their corresponding hydrothermal carbons from the non-catalyst runs. [ABSTRACT FROM AUTHOR]

This paper deals with the formation of host-guest systems between α-, β- and γ- cyclodextrins and the anionic cluster [B10H9NCCH3]-. The inclusion processes within cyclodextrins were evidenced in solution by ESI-MS and NMR, while ITC measurements provided thermodynamic parameters and affinity constants with cyclodextrin. These studies confirm the chaotropic character of this anion and evidence inclusion processes much more favored than that found for the dianionic [B10H10]2- cluster previously reported. This result evidences that playing on the volume and the charge of chaotropic systems can dramatically improve the encapsulation process within cyclodextrins. [ABSTRACT FROM AUTHOR]

In this study, the inclusion complexes of α-, β-cyclodextrins and derivatives hydroxypropyl-α-, hydroxypropyl-β-cyclodextrins with uracil and the anti-cancer agent 5- fluorouracil were demonstrated by UV-Vis spectroscopy and quantum chemical calculations. The complexes stability constants and the thermodynamic parameters for the 1:1 stoichiometry inclusion complexes were obtained and compared. The thermodynamic analysis of the studied complexes showed that the inclusion reaction is an exothermic spontaneous reaction and is an enthalpy driven process for the temperature domain of 298K to 313K. Theoretical calculations were performed on complexes to examine the energetic quantities involved in the stability of the complexes. The correlation of the energy parameters obtained from experimental and theoretical data suggests a high affinity between cyclodextrins and both uracil and 5-fluorouracil molecules. [ABSTRACT FROM AUTHOR]