A galacturonan from Dioscorea opposita Thunb. regulates fecal and impairs IL-1 and IL-6 expression in diarrhea mice.

Antibiotic-associated diarrhea (AAD) is a common side-effect of antibiotic treatment resulting from an imbalance in the colonic bacteria. The hypothesis of this study is to ask whether polysaccharide from the rhizome of Dioscorea opposita which is recorded as conventional herbs and food for diarrhea treatment in Southeast Asia, may be an active compound against diarrhea induced by antibiotics. To address, firstly, a homogenous polysaccharide, DOP0.2-S-3 was characterized as a homogalacturonan containing linear repeating units of → 4)-α-D-GalAp(1 → 4)-α-D-GalAp(1 → with the average molecular weight of 14 kDa. DOP0.2-S-3 significantly reduced the water content and defecation times caused by AAD in mice, while it also remarkably attenuated the cytokines of IL-1ß and IL-6 expression in mice colon tissues. DOP0.2-S-3 decreased potential pathogen and increased Bacteroidetes in the mice gut. These results suggested DOP0.2-S-3 might be a new leading compound for the functional foods or drug candidate development against AAD partially through regulating gut flora.

[High Throughput Screening Analysis of Preservatives and Sweeteners in Carbonated Beverages Based on Improved Standard Addition Method].

Simulated water samples of 3 kinds of preservatives and 4 kinds of sweeteners were formulated by using orthogonal design. Kernel independent component analysis (KICA) was used to process the UV spectra of the simulated water samples and the beverages added different amounts of the additive standards, then the independent components (ICs), i. e. the UV spectral profiles of the additives, and the ICs' coefficient matrices were used to establish UV-KICA-SVR prediction model of the simulated preservatives and sweeteners solutions using support vector regression (SVR) analysis. The standards added beverages samples were obtained by adding different amounts level of additives in carbonated beverages, their UV spectra were processed by KICA, then IC information represented to the additives and other sample matrix were obtained, and the sample background can be deducted by removing the corresponding IC, other ICs' coefficient matrices were used to estimate the amounts of the additives in the standard added beverage samples based on the UV-KICA-SVR model, while the intercept of linear regression equation of predicted amounts and the added amounts in the standard added samples is the additive content in the raw beverage sample. By utilization of chemometric "blind source separation" method for extracting IC information of the tested additives in the beverage and other sample matrix, and using SVR regression modeling to improve the traditional standard addition method, a new method was proposed for the screening of the preservatives and sweeteners in carbonated beverages. The proposed UV-KICA-SVR method can be used to determine 3 kinds of preservatives and 4 kinds of sweetener in the carbonate beverages with the limit of detection (LOD) are located with the range 0.2-1.0 mg · L⁻¹, which are comparable to that of the traditional high performance liquid chromatographic (HPLC) method.

From 1D zigzag chain to 1D tubular structure, weak field ligand-dependent assembly of cucurbit[6]uril-based tubular coordination polymer.

The reaction of cucurbit[6]uril with Cu(NO3)2 and CuCl2, respectively, generates a 1D zigzag chain of {[Cu(H2O)4(cucurbit[6]uril)].(NO3)2.(H2O)8}n and a 1D tubular structure of {[Cu(H2O)2(Cl)2(cucurbit[6]uril)](1/3).(H2O)3}n, showing clearly how to control the reversible and mutual interconnections between ligand and metal ion under the guide of coordination chemistry.

[Determination and comparison of metal elements in Huai radix rehmanniae at different grades by ICP-MS].

The Huai radix rehmanniae at different grades was pretreated by wet digestion, and then the metal elements in the radix rehmanniae and the prepared sample by steaming method were determined using ICP-MS. The results indicate that there is no obvious difference in the metal elements between the different grades and between the dried radix rehmanniae and its corresponding prepared product. There are elements Zn, Cu, Cr, Fe, Mn, Sn, Ni, Mo, Go, etc. in radix rehmanniae, among which the contents of Ca, Fe, Al, Zn and Cu are higher; the metal elements beneficial to human body in dried radix rehmanniae are relative lower than that in the prepared one. The elements such as Co, Ni, Cr, Mn, etc. in radix rehmanniae have poison effects on human body when their contents are more than a certain threshold value, although they are human essential elements. Element Pb is harmful to human body, which should be controlled and reduced/eliminated in the processing procedure. The determination and comparison of the metal elements in radix rehmanniae at different grades can provide useful information about the comprehensive evaluation of dried radix rehmanniae and their prepared products.

[Joint inhibition of benzene and monosubstituted benzenes on ammonia-oxidizing activity of sediment].

The joint inhibitions of benzene and three kinds of monosubstituted benzenes (aniline, phenol and nitrobenzene) on ammonia-oxidizing activity of sediment was investigated in order to study the effects of combined pollutants on nitrification process in the nitrogen cycle. The results showed that the joint inhibiton of 11 different kinds of mixtures, including binary or multi-equitoxic mixtures among benzene, aniline, phenol and nitrobenzene, exhibited different effects on ammonia-oxidizing activity of sediment, among which seven were addictive effect, three were synergistic, and only the mixture of benzene and phenol was antagonism. A conclusion could be made that the addition of nitrobenze to a mixture usually exhibited addictive effect. There was a relationship between the half joint inhibition concentrations (IC50, micromol x L(-1)) of benzene and monosubstituted benzenes on ammonia-oxidizing activity of sediment and the mixed electronegativities (MEs): lgIC50 = 2.197 - 0.236ME. With the increase of mixed electronegativities (MEs), the joint inhibitions of mixtures increased.

[Inhibition of aromatics on ammonia-oxidizing activity of sediment].

The inhibition of 24 aromatics on ammonia-oxidizing activity of nitrifying bacteria in sediment was measured. The effects of the kind, number and position of substituted groups on ammonia-oxidizing activity of nitrifying bacteria were discussed. The inhibition of mono-substituted benzenes on ammonia-oxidizing activity of nitrifying bacteria were in order of -OH > -NO2 > -NH2 > -Cl > -CH3 > -H. The position of substituted groups of di-substituted benzenes also affected the inhibition, and the inhibitions of dimethylbenzenes(xylene) were in order of meta-> ortho-> para-. The increase in number of substituted group on benzene-ring enhanced the inhibition of aromatics studied in this study on nitrifying bacteria. There was a linear relationship between inhibition (IC50, mumol.L-1) of aromatics on ammonia-oxidizing activity and total electronegativity (sigma E) of aromatics: lgIC50 = 14.72 - 0.91 sigma E.