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Diosmin (DSN) is found mainly in citrus fruits, and has potent antioxidant effects. This study aimed to evaluate pharmacokinetics of diosmetin-7-glucoside-γ-cyclodextrin (DIOSG-CD) inclusion complex. The area under the curve values from AUC0-24 of DIOSG-CD, prepared by reacting DSN and naringinase with γ-CD, were approximately 800-fold higher than those of DSN following their administration in Sprague-Dawley rats.

The pharmacokinetics of compounds comprising hesperetin-7-glucoside with β-cyclodextrin and physically mixed hesperidin/dextrin was compared in 8 healthy adult male subjects in a nonrandomized, double-blind, cross-over, controlled study. For 0-24 h, the area under the curve of the total plasma hesperetin concentration after hesperetin-7-glucoside with β-cyclodextrin consumption was >100-fold higher than that after hesperidin/dextrin consumption.

Catechins are a part of the chemical family of flavonoids, a naturally occurring antioxidant, and a secondary metabolite in certain plants. Green tea catechins are well recognized for their essential anti-inflammatory, photo-protective, antioxidant, and chemo-preventive functions. Ultraviolet radiation is a principal cause of damage to the skin. Studies observed that regular intake of green tea catechins increased the minimal dose of radiation required to induce erythema. The objectives of this systematic review and meta-analysis are to determine the effectiveness of green tea catechins in cutaneous erythema and elucidate whether green tea catechin consumption protects against erythema (sunburn) inflammation. A comprehensive literature search was conducted to identify the relevant studies. Two researchers carried out independent screening, data extraction, and quality assessment according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). The pooled effect of green tea catechins on protection against erythema was assessed using approaches fixed-effects or random-effects model to quantify the effectiveness of green tea catechins in the erythema dose–response. Studies not be included in meta-analyses were summarized narratively. Six randomized controlled studies of enrolled studies regularly administrated green tea catechins orally for 6 to 12 weeks involving healthy volunteers comprising a total of 100 participants were included in the analysis. The results revealed green tea catechins have favorable protection against erythema inflammation even at increased minimal erythema dose (MED) of ultraviolet radiation. Meta-analysis results confirm oral supplementation of green tea catechins is highly effective at low-intensity ultraviolet radiation-induced erythema response (MED range; 1.25–1.30) compared to placebo, showing a significant pooling difference (p = 0.002) in erythema index (SMD: −0.35; 95% CI, −0.57 to −0.13; I2 = 4%, p = 0.40) in the random-effects model. The pro-inflammatory signaling pathways through oral supplementation with green tea catechins are an attractive strategy for photo-protection in healthy human subjects and could represent a complementary approach to topical sunscreens. Therefore, studies that involved green tea catechin in topical applications to human subjects were also evaluated separately, and their meta-analysis is presented as a reference. The evidence indicates that regular green tea catechin supplementation is associated with protection against UV-induced damage due to erythema inflammation.

Randomly ordered mesoporous silicas hollow microspheres of 20-50 μm in diameter with distinguished characteristic of interconnected porosity (7-14 nm) of their thin outer walls are developed. Food grade emulsifier polyglycerol esters of fatty acids (PGEFA) are used as a soft-template and n-decane as a swelling agent, which was necessary for the formation of silica doped micelles to improve the mesoporous channel orientation without leading the phase transition. The interconnected pore channels that extend from the outside of the microspheres shell to its inside are used to fill the mesoporous silicas microspheres for enhanced encapsulation of VB3 precursor and cumulative in vitro release of vitamin B3 with considerable rate pharmacokinetics using simple pH trigger mechanism for the delivery systems. Refereed/Peer-reviewed

The present study reports the divergent synthesis, characterization and catalytic properties of different generation of triazine based aromatic amine dendritic mesoporous silicas derived via a stepwise functionalization of mesoporous silica substrates of different pore sizes with 2,4,6 tricholorotriazine and ethylene diamine. Mesoporous dendritic silicas up to second generation (2G) are grown in side the channels of mesoporous silica materials with 4 and 7 nm pore sizes. The catalytic properties of resulted dendritic materials in Knoevenagel condensation reaction were compared to the aliphatic polyamidoamine dendrimers that are also grown up to second generation (2G) inside the mesoporous channels. The reusability study of both aliphatic and aromatic dendritic mesoporous silica systems is also compared.

The phenylene-bridged hybrid mesoporous silica material with well-defined cubic three-dimensional (Pm3n) symmetry was prepared using a allylorganosilane precursor 1,4-bis(triallylsilyl)benzene and cetyltrimethylammoniumchloride (C16TMACl) surfactant in acidic medium. Sulfonic acid functionalized derivatives of 3d-cubic phenylene-bridged hybrid mesoporous silica materials were prepared and found effective in Friedel–Crafts acylation reaction. The catalytic results were also compared to the sulfonic acid functionalized derivatives of phenylene-bridged mesoporous silica with 2d-hexagonal (P6mn) symmetry, sulfonated SBA-1 (Pm3n) mesoporous silica, and sulfonated phenyltrimethoxy silane (PTMS) grafted SBA-1 (Pm3n) mesoporous silica. The degree of sulfonation could be controlled using the different sulfonating agents as well as the time on sulfonation. It was revealed that 3d-cubic mesoporous hybrids could be functionalized with higher concentration of sulfonic acid moieties. Friedel–Crafts acylation reaction was performed over all sulfonated materials. Mesoporous materials derived from allylorganosilane precursors showed an excellent activity in Friedel–Crafts acylation of aromatic ether anisol using acetic anhydride as acylating agent.

The first catalytic applications of sulfonic acid-functionalized hydrophobic mesoporous benzene–silica with lamellar pore wall structure are reported. The mesoporous benzene–silica attached with propylsulfonic groups to the crystal-like periodic pore walls exhibited the catalytic activity in the esterification of acetic acid with ethanol. The catalytic results show the higher conversion compared to the commercial Nafion-H.

Organosilica porous solids containing chiral organic moieties in the framework with an enantiomeric purity of 95% ee, estimated by eluting organic constituent units from chiral organosilicas, were synthesized from a newly designed chiral (R)-(+)-1,2-bis(trimethoxysilyl)phenylethane precursor via a surfactant-mediated self-assembly approach.

Structural parameters and physicochemical properties of asphaltenes separated from light Arabian mix short residue and its visbroken products (500 °C) obtained from soaker visbreaking were determined by i.r., n.m.r., v.p.o. and other classical techniques. The variations of these parameters with severity of operation measured in terms of conversion (yield of material boiling

We report that 2,6-naphthylene-bridged periodic mesoporous organosilicas exhibit unique fluorescence behavior that reflects molecular-scale periodicities in the framework. Periodic mesoporous organosilicas consisting of naphthalene-silica hybrid frameworks were synthesized by hydrolysis and condensation of a naphthalene-derived organosilane precursor in the presence of a template surfactant. The morphologies and meso- and molecular-scale periodicities of the organosilica materials strongly depend on the synthetic conditions. The naphthalene moieties embedded within the molecularly ordered framework exhibited a monomer-band emission, whereas those embedded within the amorphous framework showed a broad emission attributed to an excimer band. These results suggest that the naphthalene moieties fixed within the crystal-like framework are isolated in spite of their densely packed structure, different from conventional organosilica frameworks in which only excimer emission was observed for both the crystal-like and amorphous frameworks at room temperature. This key finding suggests a potential to control interactions between organic groups and thus the optical properties of inorganic/organic hybrids.

Highly ordered mesoporous three-dimensional Ia3d silica (KIT-6) with different pore diameters has been synthesized by using pluronic P123 as surfactant template and n-butanol as cosolvent at different synthesis temperatures in a highly acidic medium. The materials were characterized by XRD and N2 adsorption. The synthesis temperature plays a significant role in controlling the pore diameter, surface area, and pore volume of the materials. The material prepared at 150°C, KIT6-150, has a large pore diameter (11.3 nm) and a high specific pore volume (1.53 cm3 g -1). We alsodemonstrate immobilization of lysozyme, which is a stable and hard protein, on KIT-6 materials with different pore diameters. The amount of lysozyme adsorbed on large-pore KIT-6 is extremely large (57.2 μmolg -1) and is much higher than that observed for mesoporous silicas MCM-41, SBA-15, and KIT-5, mesoporous carbons, and carbon nanocages. The effect of various parameters such as bufferconcentration, adsorption temperature, concentration of the lysozyme, and the textural parameter of the adsorbent on the lysozyme adsorption capacity of KIT-6 was studied. The amount adsorbed mainly depends on solution pH, ionic strength, adsorption temperature, and pore volume and pore diameter of the adsorbent. The mechanism of adsorption on KIT-6 under different adsorption conditions is discussed. In addition, the structural stability of lysozyme molecules and the KIT-6 adsorbent before and after adsorption were investigated by XRD, nitrogen adsorption, and FTIR spectroscopy. Refereed/Peer-reviewed

A novel bush-like morphology of mesostructured silica having stems, branches, and leaves has been grown under mild basic conditions via auxiliary solvent evaporation induced self-assembly process.

The first example of ammoximation of bulky ketones over highly hydrophobic titanium incorporated ethane bridged hybrid mesoporous silsesquioxane with high selectivity of oximes is presented.

A solid catalyst, Mg–Al hydrotalcite containing nanometer size rhodium particles, is active for liquid phase methanol carbonylation to methyl acetate at 473 K in the presence of methyl iodide.

A novel approach for the synthesis of sulfonic acid functionalized periodic mesoporous silicas via covalent attachment of 2-(3,4 epoxycyclohexyl)ethyltrimethoxysilane or 3-glycidoxypropyltrimethoxysilane followed by reaction with sulfite ions and mild hydrochloric acid is presented. The materials demonstrated superior catalytic performance in esterification, acylation, and condensation reactions. The hydrophobic nature along with the crystalline pore wall structure of these materials are advantageous in increasing reaction rates by altering local water concentration and helpful in adjusting the modest active sites and surface properties. The materials also showed the higher stability and easily recyclable.

A post-synthetic process to create functionalized mesoporous dendritic silicas with a high density of tertiary amino groups is presented. Polyamidoamine periodic dendrimers up to the second generation were grown inside the channels of mesoporous hybrids. The results demonstrate that the novel polyamidoamine dendritic mesoporous benzene-silicas with highly hydrophobic crystal-like pore wall structures and the polyamidoamine dendritic mesoporous silicas with amorphous pore wall structures are very effective catalysts in Knoevenagel condensation due to enhanced hydrophobic interactions in the pore framework system, and also are effective adsorbents for volatile organic compound (VOC) removal.

The synthesis of three-dimensional (Pm3n) cubic phenylene-bridged hybrid mesoporous silica material using a novel allylorganosilane precursor 1,4-bis(triallylsilyl)phenylene and cetyltrimethylammoniumchloride (C16TMACl) as a structure-directing agent in acidic medium is presented. Sulfonic acid functionalized derivatives of these materials are effective in Friedel–Crafts acylation reactions and in controlling the atmosphere emission of volatile organic compounds, which are responsible for ground level ozone, air toxicity and smog.

The synthesis of a new class of sulfuric acid-functionalized ethane-bridged, mesoporous hybrid organosilicas is reported where the propylsulfonic groups attached with ethane-bridged silica exhibited reasonable catalytic activity in esterification of acetic acid with ethanol as well as the hydrolysis of cyclohexylacetate. Materials were synthesized by co-condensation of ethane-bridged organosilane (MeO)3SiCH2CH2Si(OMe)3 with 3-mercaptopropyltrimethoxysilane (MeO)3SiCH2CH2CH2SH in the presence of octadecyltrimethylammonium chloride surfactant. Powder X-ray diffraction patterns and nitrogen sorption analysis reveal the formation of mesoporous material with uniform porosity. The maximum content of incorporated mercaptopropylsilane in the mesoporous framework obtained was 3.45 mmol g−1. The thiol (–SH) moieties of mercaptopropyl groups that protrude into the pore channels are readily accessible for further oxidation. The surface moieties functionalized with propylsulfonic groups (–CH2CH2CH2–SO3H) were generated by the controlled oxidation of propylthiol surface groups using concentrated HNO3. A maximum acid exchange capacity (acid–base titration methods) of 1.38 H+ mmol g−1 was achieved after oxidation. Further, the materials were characterized using elemental analysis, FT-IR, 29Si and 13C MAS-NMR, transmission electron microscopy and TGA. Two probe reactions, the esterification of acetic acid with ethanol and its reverse the hydrolysis of cycloacetonate, showed the significance of the material in catalytic applications. The catalytic results showed the esterification activity is comparable to that of commercial Nafion-H and also the involvement of hydrophobic nature of the material in the hydrolysis reaction.