Direct asymmetric aldol reactions catalyzed by lipase from porcine pancreas.

Porcine pancreas lipase type II (PPL II) exhibited unnatural catalytic activity in direct asymmetric aldol reactions between cyclic ketones and aromatic or heteroaromatic aldehydes in acetonitrile in the presence of phosphate buffer. A wide range of substrates was accepted by the enzyme to afford the corresponding aldol products in low to high yields (10-98%), with moderate to excellent enantioselectivities (53-94% ee, for anti-isomers) and low to moderate diastereoselectivities (48/52-87/13 dr, anti/syn). This methodology expands the application of PPL II, and it might be developed into a potentially valuable method for sustainable organic synthesis.

[Health Risk Assessment of Heavy Metals in Soil and Wheat Grain in the Typical Sewage Irrigated Area of Shandong Province].

Sewage irrigation is a common alternative to make up for the shortage of agricultural irrigation in intensive agricultural areas. Abundant organic matter and nutrients in sewage can improve soil fertility and crop yield, but hazardous materials, such as heavy metals, will damage the soil environmental quality and threaten human health. To better understand the characteristics of heavy metal enrichment and potential health risk in a sewage irrigated soil-wheat system, a total of sixty-three pairs of topsoil and wheat grain samples were collected from the sewage irrigated area of Longkou City in Shandong Province. The contents of Cr, Cu, Ni, Pb, Zn, As, Cd, and Hg were determined to analyze heavy metal contamination and calculate bio-accumulation factor (BAF), estimated daily absorption (EDA), as well as hazard quotient (HQ). The results showed that the average contents of the eight heavy metals were 61.647, 30.439, 29.769, 36.538, 63.716, 8.058, 0.328, and 0.028 mg·kg-1, respectively, which all exceeded the background values of corresponding heavy metals in the eastern Shandong Province. Especially, the average content of Cd was higher than the current standard value of soil environmental quality of agricultural land soil pollution risk control, indicating the apparent soil contamination. However, the correlations between the heavy metal contents in soil and wheat grains were not significant, suggesting that it is difficult to conclude the enrichment degree of heavy metals in wheat grains merely by the heavy metal contents in soil. The results of BAF showed that the high enrichment capacity of wheat grain was primarily obtained with Zn, Hg, Cd, and Cu. According to the national food safety limit standard, the over-limit ratios of Ni (100%) and Pb (96.8%) in wheat grains were the most serious. As a result, under the current consumption of local wheat flour, the EDAs of Ni and Pb were high, accounting for 28.278% and 1.955% of the acceptable daily intakes (ADI) for adults and 131.980% and 9.124% of the ADIs for children. The results of the health risk assessment exhibited that As and Pb were the main sources causing health risks, accounting for approximately 80% of the total risk. Although the sums of the HQ of the eight heavy metals for adults and children were below 10, the total HQ of children was 1.245 times higher than that of adults. The food safety of children should receive more attention. When considering spatial characteristics, the health risk in the southern study area was higher than that in the northern part of the study area. The prevention and control of heavy metal contamination in the southern area should be strengthened in the future.

[Effects of oligomeric grape seed proanthocyanidins on isoproterenol-induced cardiac remodeling in rats].

The purpose of this study is to evaluate the effect of oligomeric grape seed proanthocyanidins (GSP) on isoproterenol (ISO)-induced cardiac remodeling in rats. ISO was given subcutaneously (5 mg x kg(-1), sc, 7 days) to induce cardiac remodeling in rats. Therapeutic groups were given GSP (50, 100, and 150 mg x kg(-1)) after ISO treatment. After 2 weeks intervention, heart rate (HR), left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), rate of rise of left ventricular pressure (+/- dp/dt(max)) were examined. The myocardial hypertrophy index was expressed as heart weight/body weight (HW/BW) and left ventricle weight/body weight (LVW/BW), the histological changes were investigated by HE and Van Gieson stain. SOD activity and MDA content in serum, contents of hydroxyproline (Hyp) in the left ventricular tissue were assayed by xanthinoxidase method, thiobarbituric acid (TBA) method and alkaline hydrolysis method, respectively. After the onset of ISO-treatment, GSP therapy potently improved cardiac function, inhibited myocardial hypertrophy, improved cardiac pathology change, decreased the myocardial cross-section area (CSA), collagen volume fraction (CVF) and perivascular circumferential collagen area (PVCA), reduced the content of Hyp in the left ventricular tissue, inhibited the decrease of SOD activity and increase of MDA content in serum. GSP possess protective effect against ISO induced cardiac remodeling in rats, this may be related to reducing the oxidative stress and improving antioxidant capacity.

[Ecological Risk Assessment of Soil Heavy Metals for Different Types of Land Use and Evaluation of Human Health].

Surface soils were collected from five types of land use in the northern plain of Longkou City and the contents of five heavy metals (Cu, Pb, Zn, Cd, and As) were determined. Based on results from preliminary studies on heavy metal pollution of soil, the potential ecological risks caused by heavy metals in the soil and risks to human health were evaluated using the Hakanson potential ecological risk assessment model after adjusting the evaluation threshold and the health assessment model after modifying parameters. The results show that the contents of five heavy metals in the study area exceed the background value, the potential ecological risk of Cd is high and complex, in irrigated land, orchard land, and bare land it is mostly the second-class risk, and urban industrial land and mining land are dominated by severe risk. The element As is equivalent to the first two levels of each land class; the minor risk areas of the other three types of heavy metals are larger than 70%. The comprehensive ecological risk of the five elements is higher than the three-level risk in the field, except for the bare ground. The area of four-level risk of urban industrial land and mining land is relatively large. The five types of soil heavy metals in this area present noncarcinogenic and carcinogenic risks to human health. The element Pb and heavy metal As, both entering the body by oral intake, pose a noncarcinogenic and carcinogenic risk to adults and children, respectively.

[Spatial Characteristics and Environmental Risk of Heavy Metals in Typical Gold Mining Area of Shandong Province].

In order to reveal the influence of anthropogenic factors on soil environment quality, a total of seventy-seven samples in topsoils were collected from Jiaojia gold mining area in Shandong province and were determined for Cu, Pb, Zn, Cr contents. Spatial structure, spatial distributions of concentrations and risk probability of heavy metals were analyzed using spatial statistic analysis. The average concentrations of Cu, Pb, Zn and Cr were 19.41 mg·kg-1, 27.32 mg·kg-1, 49.81 mg·kg-1 and 39.27 mg·kg-1, respectively. Pb, Zn and Cr were distributed normally and Cu was distributed normally after logarithm transformation. Semivariance analysis demostrated that Pb could be fitted to exponential model, and Cu, Zn and Cr were fit for spherical model. Nugget coefficents of Cu and Pb were between 0.25 and 0.75, which illustrated middle spatial autocorrelation; Zn and Cr showed the structural variation with nugget values below 0.25. Cu and Pb in the topsoils were distributed dispersedly due to effects of some human factors, whereas contents of Zn and Cr indicated relatively regular distributions and were mainly affected by natural factors. Spatial distributions of the 4 heavy metals were approximately consisitent and the high value areas appeared in the gold mines band. The result of hot spot analysis and indicator kriging interpolation revealed that the relatively high risk areas were located in Jincheng town, the boundary zone of Xinzhuang town and Canzhuang town, while the safe zone was situated in south part of the study area. Pb had higher probability exceeding the threshold and the middle or high environmental risk areas of Pb were distributed widely, which should be paid more attentions.