Authors:M. Zheng, Y. Tian, H. Teng, J. Hu, F. Wang, Y. Zhao, and L. Yu
In this paper, the wind energy resource in China’s oilfields is analyzed, the difference between China’s energy consumption structure and that of the world in average is analyzed as well, and the application prospect of wind heating technology in China’s oilfields is discussed as an example to reform China’s energy consumption structure. It shows that it is possible to use wind energy as an appropriate heat resource or supplementary heat source in some oilfields to supply heat energy for oil heating and living, more room to improve the energy resource utilization in various fields in China remain. It is a benefit to both oilfield and society to improve energy saving and environments.
Authors:R.D. Wang, Y.J. Deng, L.J. Sun, Y.L. Wang, Z.J. Fang, D.F. Sun, Q. Deng, and R. Gooneratne
Growth and haemolytic activity of several pathogenic Vibrio species were compared in egg-fried-rice with different egg ratios. Egg-fried-rice preparations with rice-to-egg ratios of 4:1, 1:1, and 1:4 were inoculated with either Vibrio parahaemolyticus, V. cholerae, V. vulnificus, or V. alginolyticus and incubated for 24 h. Cell number, thermostable direct haemolysin (TDH) activity, and total haemolytic activity were determined. The cell number and total haemolytic activity increased in all Vibrio strains after 24 h, and these were most marked in egg-fried-rice with the highest egg content (1:4 (rice:egg) ratio; P<0.05). V. alginolyticus exhibited the maximal growth and V. parahaemolyticus the highest haemolytic activity, but only V. parahaemolyticus ATCC 33847, V. alginolyticus CAMT 21162, and V. alginolyticus HY 91101 showed TDH activity. Results suggest that lowering egg content in egg-fried-rice could reduce growth and virulence of Vibrio pathogens.
Authors:G.W. Shu, D.L. Ma, H. Chen, J.P. Meng, Y. Wang, and N. Xin
The present study was to evaluate the survival rate of free and encapsulated Bifidobacterium bifidum BB28 under simulated gastrointestinal conditions and its stability during storage. Results showed that non-microencapsulated Bifidobacterium bifidum BB28 was more susceptible to simulated gastrointestinal conditions than microencapsulated bacteria. Microencapsulated Bifidobacterium BB28 exhibited a lower population reduction than free cells during exposure to simulated gastrointestinal conditions, the viable count of monolayer microcapsules, double layer microcapsules, and triple layer microcapsules decreased by nine magnitudes, four magnitudes, and one magnitude after 2 h, respectively. The enteric test showed that the microorganism cells were released from the monolayer, double layer, and triple layer microcapsules completely in 40 min. Moreover, the optimum storage times of free Bifidobacterium BB28, monolayer microcapsules, double layer microcapsules, and triple layer microcapsules were 21 days, 21 days, 28 days, and more than 35 days in orange juice, pure milk, and nutrition Express (a commercially available milk based drink), and the viable counts were maintained at 1×106 CFU g−1 or more, which means that the double layer and triple layer of microcapsules of B. bifidum BB28 have great potential in food application.
Authors:Z. Fang, D. Sun, J. Gao, M. Guo, L. Sun, Y. Wang, Y. Lıu, R. Wang, Q. Deng, D. Xu, and R. Gooneratne
Shewanella putrefaciens supernatant was found to increase the virulence factors of Vibrio parahaemolyticus by eﬃciently degrading its acylhomoserine lactone (AHL). To further reveal the regulation mechanism and its key degrading enzyme, a potential AHL-degrading enzyme acylase (Aac) from S. putrefaciens was cloned, and the inﬂuences of temperature, pH, protein modiﬁers, and metals on Aac were tested. Aac was signiﬁcantly inﬂuenced by temperature and pH, and exhibited the highest AHL-degrading activity at temperatures of 37 °C and pH of 8. Mg2+ and Fe2+ can further increase the AHL-degrading activity. 10 mM EDTA inhibited its activity possibly by chelating the co-factors (metals) required for Aac activity. Tryptophan and arginine were identiﬁed as key components for Aac activity that are critical to its AHL-degrading activity. This study provides useful information on Aac and for V. parahaemolyticus control.