Research Progress on the Development and Application of New Natural Tobacco Humectants

The research progress on the development and application of new natural tobacco humectants was reviewed in the paper.Plants,animals and microbes contain special moisturizing substances,showing distinctive advantages and outstanding effects in respect of the tobacco moisture content maintaining and cigarette suction comfort promoting.The development necessity,major types,functional mechanism and influence on cigarette quality of new natural tobacco humectants development were compared and elaborated.Additionally,the prospect of new natural tobacco humectants development and application was forecasted.

Comparison of Different Cartridges of Solid Phase Extraction for Determination of Polyphenols in Tobacco by UPLC/MS/MS and Multivariate Analysis

The comparison of solid phase extraction（SPE） for the preconcentration and isolation of polyphenols in tobacco samples was carried out by ultra-high performance liquid chromatography/tandem mass spectrometry （UPLC/MS/MS） and multivariate analysis.Several adsorbing materials of SPE（C18,NH2,SAX and OASIS） were investigated.It was found that the C18 and OASIS cartridges can not only speed up the purification process,but also simplify the SPE operation.A UPLC/MS/MS was used for the determination of polyphenols in tobacco samples after purification.All analytes were separated and determined in 2min.The limit of detection was 0.05 ng/mL.Cluster analysis（CA） and principal component analysis（PCA） were used for the analysis of 4 varieties（flue-cured tobacco,oriental tobacco,sun-cured tobacco and burley） in order to interpret the effect of planting and machining process on the concentration of polyphenols.The different types of tobacco samples could be easily clustered by CA.PCA on the chemical composition of tobacco resulted in two principal components（PCs） that take 84.2% of the total variance.The PCA and CA indicate that the polyphenols can be used for distinguishing tobacco types.

Sesquiterpenes from the leaves of Nicotiana tabacum and their anti-tobacco mosaic virus activity

In searching for more bioactive compounds, phytochemical investigations on the acetone extract of the leaves ofNicotiana tabacurn resulted in the isolation of two new sesquiterpenes, nicosesquiterpene A and B （1 and 2）, along with four known sesquiterpene derivatives （3-6）. Structural elucidation of I and 2 was performed by spectral methods, such as HRMS, IR, UV, 1D and 2D NMR spectroscopy. Compounds 1 and 2 are the first naturally occurring pterosin-type sesquiterpene bearing an isopropyl moiety. Compounds 1-6 were also evaluated for their anti-tobacco mosaic virus （anti-TMV） activity. The results showed that compounds 1 and 2 exhibited high anti-TMV activity with inhibition rates of 36.7% and 45.6%, respectively, which is higher than that of positive control. The other compounds also showed potential activity with inhibition rates in the range of 22.7%-29.2%.

Three new nortriterpenoids from Schisandra wilsoniana and their anti-HIV-1 activities

Three new highly oxygenated nortriterpenoids,wilsonianadilactones D-F(1-3),were isolated from the leaves and stems of Schisandra wilsoniana.Their structures were established by means of spectroscopic analysis.Compounds 1-3 showed weak anti-HIV-1 activity with the therapeutic index(TI)values(CC50/EC50)greater than 8.16,14.7,and 17.5,respectively.

Characterization of particle size distribution of mainstream cigarette smoke generated by smoking machine with an electrical low pressure impactor

Cigarette smoking is a particle-related exposure. Studying the characteristics of the particle size distribution of cigarette smoke can aid in providing knowledge of smoke aerosol attributes. We used an electrical low pressure impactor （ELPI） to measure the particle size distribution of mainstream cigarette smoke generated by a smoking machine and provided a continuum of particle sizes of cigarette smoke from a whole cigarette. The results showed that the aerodynamic diameters （D, geometric mean of a channel） of particles ranged from 0.021 to 1.956 ~m, and the number concentrations were on the order of 105-109 cm-3 for different sizes of particles. The particle number of the size category below 0.1 p,m approximated that of the category 0.1-2.0 Ixm, and the particles in the size category of 0.1-2.0 μm contributed extremely heavily to total particulate mass. In addition, the results with small samples indicated that the tar yields normalized per milligram of nicotine showed an approximately linear increase with increasing concentration of total particles.

Cytotoxic sesquiterpene aryl esters from Armillaria gallica 012m

Objective:To study the chemical constituents of the EtOAc extract of Armillaria gallica 012m.Methods:The chemical constituents of the EtOAc extract of A.gallica 012m were isolated and purified by various column chromatography and their structures were elucidated on the basis of the 1D and 2D NMR spectroscopic and HRESIMS data.Cytotoxicity of all isolates against A549,HCT-116,M231 and W256 human tumor cells was determined by the MTT method.Results:A new sesquiterpene aryl ester,armimelleolide C(1),and eight known ones including armillarivin(2),melleolide F(3),6'-chloromelleolide F(4),melleolide(5),melleolide K(6),melledonol(7),13-hydroxydihydromelleolide(8),and armillane(9),were isolated from the EtOAc extract of A.gallica 012m.All isolates showed potential cytotoxic activities against at least one of the human cancer cell lines with IC_(50) values ranging from(3.17±0.54)to(17.57±0.47)μmol/L.Compound 1 showed significant inhibitory activity against M231 with an IC_(50) value of(7.54±0.24)μmol/L compared with paclitaxel as the positive control.Compounds 2,3,and 7,9 showed obvious inhibitory activity against HCT-116 and were better than that of the positive control.Conclusion:The chemical constituents including a new sesquiterpene aryl ester armimelleolide C(1)from the EtOAc extract of A.gallica 012m have a variety of structures and potential antitumor activities.

Micro-/nanostructured ZnFe_(2)O_(4) hollow sphere/GO composite for structurally enhanced photocatalysis performance

The pollution of organic dyes has become a serious environmental problem.It is still urgent to prepare a highly efficient and environment-friendly photocatalyst for pollutants removal.Herein,a micro-/nanostructured ZnFe_(2)O_(4)hollow sphere/GO(ZnFe_(2)O_(4)/GO)composite photocatalyst was prepared through a one-step hydrothermal method with high performance and recycling property.The obtained micro-/nanostructured composite was assembled by ZnFe_(2)O_(4) hollow spheres and GO nanosheets.

Biodegradable Microspheres with Poly(N-isopropylacrylamide) Enriched Surface: Thermo-responsibility, Biodegradation and Drug Release

Microspheres with thermo-responsible surface were fabricated by PCL-b-PEO-b-PNIPAM triblock copolymers. Thermo-responsible morphological changes of PCL-b-PEO-b-PNIPAM microspheres immersed in aqueous solution at temperatures above the LCST（e.g. 37 ℃） were observed from porous surface structure to compact surface layer. Enzymatic degradation and in vitro drug release results showed that the thermo-responsible surface layer greatly influenced the degradation of microspheres as well as the drug release behavior from microspheres. With the copolymerization of PNIPAM block into PCL-b-PEO copolymers, the drug release could be well regulated by changing temperatures and microspheres composition, which revealed the great potentials of microspheres with thermo-responsible surface for controlled drug release.