Alternate Ultrasound/Microwave Digestion for Deep Eutectic Hydro-distillation Extraction of Essential Oil and Polysaccharide from Schisandra chinensis (Turcz.) Baill.

An alternating synergetic ultrasound/microwave method was applied to the simultaneous extraction of essential oils and polysaccharides with deep eutectic solvent (DES) from Schisandra chinensis. Under the optimal conditions, extract in the selected choline chloride-ethylene glycol 1:3 solvent yielded 12.2 mL/kg and 8.56 g/100g of essential oils and polysaccharides, respectively. The free radical scavenging and immunological activities of the polysaccharides and the antioxidant activity of the essential oils have also been investigated. The lymphocyte proliferation capacity was substantially improved by adding concanavalin A or lipopolysaccharides to polysaccharides (0.20 mg/mL). The IC50 values of the essential oils for scavenging DPPH obtained by hydro-distillation and DES ultrasound/microwave-assisted hydro-distillation (DES UMHD) were 52.34 µg/mL and 29.82 µg/mL, respectively. The essential oil obtained by DES UMHD had the highest reducing power (856.05 (TE)/g) at 150 g/mL and had the strongest inhibitory capacity (SC% = 18.12%). S. chinensis has the potential to be developed as a natural antioxidant.

GC-MS Study of the Chemical Components of Different Aquilaria sinensis (Lour.) Gilgorgans and Agarwood from Different Asian Countries.

As a traditional medicinal herb and valuable natural spice in China, Aquilaria sinensis (Lour.) Gilg has many significant pharmacological effects. Agarwood is the resinous heartwood acquired from wounded A. sinensis trees, and is widely used in pharmaceuticals owing to its excellent medicinal value. In this study, the chemical composition of volatile components and alcohol extracts from different organs of A. sinensis and agarwoods grown in different regions were investigated using GC-MS. The results showed that Vietnam agarwood had the highest moisture content, which was attributed to the local climate, while the fruit and bark of A. sinensis had higher moisture contents than the other organs. The volatile components of A. sinensis organs included 3-ethyl-5-(2-ethylbutyl)-octadecane, oleic acid 3-(octadecyloxy) propyl ester, and docosanoic acid 1,2,3-propanetriyl ester, while the alcohol extracts of A. sinensis organs contained benzoic acid ethyl ester, hexadecanoic acid ethyl ester, oleic acid, and n-hexadecanoic acid. Furthermore, the main active ingredients in agarwood from different habitats were sesquiterpenoids, aromatic species, and chromone compounds. The role of chromone compound 2-phenylethyl-benzopyran as an elicitor and the mechanism of agarwood formation were also investigated. Antioxidant tests showed that essential oils from agarwood and A. sinensis had antioxidant capacities by comparison with butylated hydroxytoluene and vitamin E. An antibacterial activity test showed that the inhibition effect of the essential oil was better against Gram-positive bacteria than against Gram-negative bacteria.

Preparation of a Smart and Portable Film for in Situ Sensing of Iron Microcorrosion.

Corrosion of iron-containing materials, which presents serious economic and safety problems, normally begins with microcorrosion, which refers to the early stages of corrosion before visible changes appear on the surface. If microcorrosion could be detected and repaired immediately, corrosion damage could be greatly reduced. Current technology and materials, however, are not able to detect microcorrosion of iron in a cheap and convenient manner. Here, we have used a natural product, ellagic acid (EA), to fabricate an EA-functionalized poly(vinyl alcohol) (PVA) film (EAF) for in situ sensing of the initial stage of microcorrosion. EAF was able to effectively sense iron microcorrosion via an obvious color change. The film also had good long-term stability and mechanical strength. Since EAF can be easily prepared from inexpensive and green raw materials, the film opens up a new opportunity for the detection of iron microcorrosion.

Synthesis and activity evaluation of the cyclic dipeptides arylidene N-alkoxydiketopiperazines.

A series of arylidene N-alkoxydiketopiperazines was designed and stereoselectively synthesized via oxime-ether formation and intramolecular acylation. Possible cyclization and acid-catalyzed rearrangement-fragmentation mechanisms were discussed. The crystal structure of the novel diketopiperazine further confirmed the rearrangement mechanism. Most compounds exhibited antitumor activity. Several compounds were more potent against caspase-3. Specifically, compounds 6e, 6g, and 6f inhibited caspase-3 at IC50 values lying within the low micromolar range and demonstrated good selectivity. The binding modes of alkoxydiketopiperazines in the active center of caspase-3 were also discussed based on the molecular docking results.

One-pot, three-component synthesis of a library of spirooxindole-pyrimidines catalyzed by magnetic nanoparticle supported dodecyl benzenesulfonic acid in aqueous media.

Dodecyl benzenesulfonic acid functionalized silica-coated magnetic nanoparticles (γ-Fe2O3@SiO2-DDBSA) were readily prepared and identified as an efficient catalyst for the synthesis of a library of spirooxindole-pyrimidine derivatives by three-component condensation reaction of barbituric acids, isatins and cyclohexane-1,3-diones. The aqueous reaction medium, easy recovery of the catalyst using an external magnet, and high yields make the protocol sustainable and economic.

(Anthracen-9-ylmeth-yl)benzyl-ammonium chloride.

In the title compound, C(22)H(20)N(+)·Cl(-), the anthracene system makes a dihedral angle of 72.65 (4)° with the benzene ring. The C-N-C-C torsion angles in the chain connecting the benzene ring and anthracene system are 52.24 (15) and -170.73 (11)°. The crystal structure is stabilized by inter-molecular N-H⋯Cl and C-H⋯Cl hydrogen bonds, which link the mol-ecules into tetra-mers about inversion centers.

[Preparation and characterization of visible-light response activated carbon with antibacterial behavior].

A visible-light response activated carbon with antibacterial activity was prepared by calcinations of the mixture of TiO2 precursor obtained by acid catalyzed hydrolysis method and commercial granular activated carbon (GAC) in NH3/N2 atmosphere. The antibacterial activity of the prepared activated carbon towards E. coil was investigated under the visible-light irradiation. X-ray diffraction (XRD), Scanning electron spectroscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and N2 adsorption analyser were used to characterize the crystal phase structure, surface morphology, spectral characteristics and pore properties. The results show there is no influence for crystal phase structure of TiO2 supported AC. The crystal size of TiO2 is 9.8 nm. Non-crystal phase layer and strong adsorption force of carrier can inhibit the grain growth of TiO2, and AC combines with TiO2 in Ti-O-C so that TiO2 formestight film on AC. The sample calcinated at 500 degrees C for 5 h exhibits the highest bactericidal performance, and the bactericidal rate reached up to 67% after 4 h irradiation, which was better than that of nature light (39%) in the same condition.

[Preparation and characterization of activated carbon-silver composite with antibacterial behavior via vacuum impregnation method].

Activated carbon-silver composite (Ag/AC) for antibacterial performance by controlling silver release was prepared by silver acetate vacuum impregnation method. The antibacterial activity towards E. coil and resistance of water erosion was investigated through distilled water. Surface area and porosity analyzer, Scanning electron spectroscopy (SEM) and X-ray diffraction (XRD) were used to characterize the surface morphology and pore properties. The results show that Ag0 was deposited on AC symmetrically. The content of silver supported and particle size were increased by the increasing of the concentration of CH3 COOAg, while specific surface area, total pore volume and average pore size were decreased. Ag/AC prepared with silver content of 0.97% which killed 10(7) CFU/mL concentration of E. coil in 120 min exhibited the similar antibacterial activity for E. coil with that prepared by traditional impregnation method. However, the silver loss of the Ag/AC prepared with silver content of 0.97% was 37.6%, showing much higher resistance to water erosion. High antibacterial activity and control silver release can be simultaneously realized by the silver acetate vacuum impregnation method.

[Preparation and characterization of activated carbon-silver composite with antibacterial behavior via NaBH4 reduction method].

Activated carbon-silver composite (Ag/AC) for antibacterial behavior with capability of controlling silver release was prepared by NaBH4 reduction method. The antibacterial activity towards E. coil and resistance of water erosion was investigated through a point of view of water purification. N2 adsorption isotherm, Scanning electron spectroscopy (SEM)-Energy dispersive X-ray spectrometer(EDS) and X-ray diffraction(XRD) was used to characterize the surface morphology and pore properties. As an experiment result, silver was deposited on AC in the state of Ag0. The content of silver supported, specific surface area, nucleus formation and growth mechanism, particle size and distribution of the generated silver particles were determined by the concentration of the aqueous solution of AgNO3. With the increasing of AgNO3 solution concentration, the activity of the obtained Ag/AC changed from non-active to inhibitory and then to high antibacterial. Ag/AC supported silver content of 2.70% killed all the concentration of 2 x 10(6) CFU/mL of E. coil. However, it showed high resistance to water erosion that silver loss was 21.1% in 600 h for surging. High antibacterial activity and control silver release can be simultaneously realized by the NaBH4 reduction method.

Dimethyl 2-(2-quinolylmeth-yl)malonate.

In the title compound, C(15)H(15)NO(4), the quinoline ring system and one of the malonate side chains are essentially coplanar (r.m.s. deviation = 0.0297 Å). The two malonate C-C(=O)-O-CH(3) side chains are oriented at right angles [89.68 (8)°] with respect to each other. The crystal packing is stabilized by weak non-classical inter-molecular C-H⋯O hydrogen bonds, which link the mol-ecules into dimers about inversion centers.

Dimethyl 2-(2,4,6-trimethoxy-benz-yl)malonate.

In the title compound, C(15)H(20)O(7), the benzene ring makes dihedral angles of 69.17 (5) and 80.81 (4)° with the two side chains of malonate. The two malonate side chains comprising C/C/O/C atoms are oriented at right angles [86.26 (6)°] with respect to each other. In the crystal structure, the crystal packing is stabilized by weak non-classical inter-molecular C-H⋯O hydrogen bonds, which link the mol-ecules into an infinite network.

11-(p-Tolylsulfonyl)-8,14,24-trioxa-11,22,23-triazatetracyclo[19.2.1.0.0]tetracosa-1(23),2,4,6,15,17,19,21-octaene.

In the title compound, C(25)H(23)N(3)O(5)S, the central 1,3,4-oxadiazole ring makes dihedral angles of 35.05 (7), 23.68 (7) and 82.55 (8)°, with the three benzene rings. In the crystal structure, the packing is stabilized by weak non-classical inter-molecular C-H⋯O hydrogen bonds, which link the mol-ecules into an infinite network.

2,5-Bis[2-(2-methoxy-ethoxy)phen-yl]-1,3,4-oxadiazole.

In the title compound, C(20)H(22)N(2)O(5), the central 1,3,4-oxadiazole ring is essentially planar [r.m.s. deviation from the best plane of 0.0011 Å] and makes dihedral angles of 4.10 (3) and 13.32 (4)° with the two benzene rings. In the crystal structure, the packing is stabilized by weak non-classical inter-molecular C-H⋯N hydrogen bonds, which link the mol-ecules into an extended network.

[Influence of surface chemical properties and pore structure characteristics of activated carbon on the adsorption of nitrobenzene from aqueous solution].

Commercial activated carbon was treated by HNO3 oxidation and then subsequently heat treated under N2 atmosphere. Effect of surface chemical properties and pore structure on the adsorption performance of nitrobenzene was investigated. N2/77K adsorption isotherm and scanning electron microscopy (SEM) were used to characterize the pore structure and surface morphology of carbon. Boehm titration, Fourier transform infrared spectroscopy (FTIR), the point of zero charge (pH(PZC)) measurement and elemental analysis were used to characterize the surface properties. The results reveal that HNO3 oxidation can modify the surface chemical properties, increase the number of acidic surface oxygen-containing groups and has trivial effect on the pore structure of carbon. Further heat treatment can cause the decomposition of surface oxygen-containing groups, and increase the external surface area and the number of mesopores. Adsorption capacity of nitrobenzene on AC(NO-T), AC(raw) and AC(NO) was 1011.31, 483.09 and 321.54 mg x g(-1), respectively. Larger external surface area and the number of meso-pores, together with the less acid surface oxygen-containing groups were the main reason for the larger adsorption capacity AC(NO-T).

[Preparation of N-doped nanosize TiO2 and spectral analysis].

Nitrogen-doped nanosize TiO2 was prepared by sol-gel method with TBT and EDA as forerunner body, ethanol as solvent and glacial acetic acid as inhibitor. The crystalline structure and spectrum character were characterzed. According to the curves of differential thermal gravimetric analysis (TG/DTA), the crystal transformation temperature and the best calcining temperature of the obtained samples were determined. According to the ultraviolet-visible diffuse reflection spectrum (UV-Vis/ DRS), the spectral absorption characteristic of the obtained samples was characterized; According to the X-ray diffraction spectrum (XRD), the particle size and crystalline phase structure of the prepared samples were determined; and according to the X-ray photoelectron spectrum (XPS), the superficial composition of the prepared samples was analyzed. The relations between the red shift degree of absorption band and the proportion of EDA/TBT and calcining temperature were investigated in this experiment. The results indicate that the crystal phase of the obtained nitrogen-doped TiO2 is anatase, and the absorption band has a red shift obviously. Both the proportion of EDA/TBT and the calcining temperature have an evident effect on the spectral absorption of the prepared samples. When the mol proportion of EDA/TBT is 1 : 10 and the calcining temperature is 600 degrees C, the spectral absorption of the prepared samples is the strongest.

(E)-4-[(1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)imino-meth-yl]phenyl 4-bromo-benzene-sulfonate.

In the title compound, C(24)H(20)BrN(3)O(4)S, the central benzene ring makes dihedral angles of 17.13 (13), 39.83 (13) and 58.37 (13)°, respectively, with the pyrazolone ring, the bromo-benzene ring and the terminal phenyl ring. In the crystal structure, the packing is stabilized by a weak non-classical inter-molecular C-H⋯O hydrogen bond which links the mol-ecules into a chain propagating in [100].

(E)-1,5-Dimethyl-4-[3-(4-nitro-benz-yloxy)benzyl-ideneamino]-2-phenyl-1H-pyrazol-3(2H)-one.

In the title compound, C(25)H(22)N(4)O(4), the central benzene ring, makes dihedral angles of 74.35 (6), 17.01 (8) and 62.19 (7)°, respectively, with the nitro-benzyl ring, the pyrazolone ring and the terminal phenyl ring. Inter-molecular C-H⋯O hydrogen bonds help to consolidate the crystal packing.

Preparation and performance of photocatalytic regenerationable activated carbon prepared via sol-gel TiO2.

Preparation of photocatalytic regenerationable activated carbon (AC) is the key step for the practical application of in situ regeneration of exhausted AC. A novel photocatalytic regenerationable AC was prepared by sol-gel TiO2 in this work. The adsorption and regeneration performance of TiO2/AC were evaluated using phenol as model compound. Scanning electron microscope (SEM) and nitrogen (77 K) adsorption isotherm were used to determine the surface area, pore structure and the distribution of TiO2. The results showed that with the increase of TiO2 loading, adsorption capacity of TiO2/AC decreased and the regeneration efficiency increased. The photocatalytic regenerationable AC with suitable TiO2 loading (2 wt%) exhibited suitable adsorption capacity and regeneration efficiency. TiO2 located mainly in the entrance of macro-pore of carbon. The prepared TiO2/AC exhibited similar surface structure and pore structure with material carbon.

[Effect of acid-base two steps surface modification on the adsorption of Cr(VI) onto activated carbon].

Effect of HNO3-NaOH two steps surface modification on the adsorption of Cr(VI) from aqueous solution onto activated carbon was evaluated. Activated carbon was oxidized in HNO3 aqueous solution at first (AC1), then treated in the mixture of NaOH and NaCl solution (AC2). Batch equilibrium and continuous adsorption experiments were conducted to determine the adsorption characteristics. Boehm titration method, element analysis were used to characterize the surface properties. N2/77 K adsorption isotherm method was used to characterize the pore structure. The results reveal that adsorption capacity and adsorption rate increase significantly, which in the following order: AC2>AC1>AC0. Surface modification caused BET surface area decreased and the total number of surface oxygen acid groups increased. First oxidation modification in HNO3 solution produced positive acid groups on the surface of activated carbon. Subsequent 2nd modification replaced H+ of carbon surface groups by Na+, the acidity of AC2 was decreased. The main cause of higher Cr(VI) adsorption capacity and rate for AC2 was the more oxygen surface acid groups, and suitable solution pH provide by surface groups.