Sixteen priority polycyclic aromatic hydrocarbons(PAHs) in surface water samples were analyzed by gas chromatograph-mass spectrometer(GC-MS) to study their distribution and characterizing sources.The water samples wer...Sixteen priority polycyclic aromatic hydrocarbons(PAHs) in surface water samples were analyzed by gas chromatograph-mass spectrometer(GC-MS) to study their distribution and characterizing sources.The water samples were collected from five sites(J1-J5) in the Jialing River of Chongqing downtown area from September 2009 to August 2010.The results demonstrate that the concentration of total PAHs in three samples upstream are relatively higher than those in other two sites downstream,with average concentration of total PAHs for each site ranging from 811.5 ng/L to 1585.8 ng/L.The 2,3 and 4-ring PAHs for sampling stations account for 13.0%,56.6% and 28.6%,respectively,in total PAHs.There are obvious tendencies of seasonal change for PAHs concentration in surface water.The PAHs concentration in April of wet season is 1 301.6 ng/L,which is 1.3 times the lowest amount of total PAHs in August of flood season.Ratios of specific PAH compounds were used to characterize the possible pollution sources.Experimental results indicate that the PAHs in surface water samples are primarily from pyrolytic PAHs because of factories along these sites,while the direct leakage of petroleum products may be significant for two sites,Jiahua Bridge(J4) and Huanghuayuan Bridge(J5),because of the wharf boat nearby.展开更多
Safflower is a popular Chinese medicinal plant and Safflower injection is extensively used for the clinical treatment of cerebrovascular and cardiovascular diseases. In this study, HPLC-DAD-ESI-MSn was utilized to stu...Safflower is a popular Chinese medicinal plant and Safflower injection is extensively used for the clinical treatment of cerebrovascular and cardiovascular diseases. In this study, HPLC-DAD-ESI-MSn was utilized to study the stability and degradation of the two major but chemically unstable bioactive compounds hydroxysaffior yellow A and anhydrosaffior yellow B, in Safflower injection. The impact of light irradiation, temperature, and pH on the stability of these two compounds were studied. The results showed that hydroxysafflor yellow A and anhydrosafflor yellow B could degrade at high temperature （〉60 ℃） or extreme pHs （pH ≤ 3.0 or 〉7.0）, but not under light irradiation. The common degradation product was p-coumaric acid. Chemical structures of the other degradation products were characterized by LC-MS. Hypothetical degradation pathways were proposed. In addition, ADP-induced platelet aggregation tests showed that the degradation of anhydrosaffior yellow B could reduce the anticoagulation activities of Safflower injection. Our results suggest that temperature and pH are critically important for the preparation and storage of Safflower injection.展开更多
基金Project(41101457) supported by the National Natural Science Foundation of ChinaProject(2009-122) supported by the Fund of Chongqing Municipal Construction Commission, China
文摘Sixteen priority polycyclic aromatic hydrocarbons(PAHs) in surface water samples were analyzed by gas chromatograph-mass spectrometer(GC-MS) to study their distribution and characterizing sources.The water samples were collected from five sites(J1-J5) in the Jialing River of Chongqing downtown area from September 2009 to August 2010.The results demonstrate that the concentration of total PAHs in three samples upstream are relatively higher than those in other two sites downstream,with average concentration of total PAHs for each site ranging from 811.5 ng/L to 1585.8 ng/L.The 2,3 and 4-ring PAHs for sampling stations account for 13.0%,56.6% and 28.6%,respectively,in total PAHs.There are obvious tendencies of seasonal change for PAHs concentration in surface water.The PAHs concentration in April of wet season is 1 301.6 ng/L,which is 1.3 times the lowest amount of total PAHs in August of flood season.Ratios of specific PAH compounds were used to characterize the possible pollution sources.Experimental results indicate that the PAHs in surface water samples are primarily from pyrolytic PAHs because of factories along these sites,while the direct leakage of petroleum products may be significant for two sites,Jiahua Bridge(J4) and Huanghuayuan Bridge(J5),because of the wharf boat nearby.
基金Changjiang Scholar and Innovative Research Team in University (Grant No. 985-2-063-112)Youth Research Fellowship of Chinese Center for Disease Control and Prevention (Grant No. 2009A203)
文摘Safflower is a popular Chinese medicinal plant and Safflower injection is extensively used for the clinical treatment of cerebrovascular and cardiovascular diseases. In this study, HPLC-DAD-ESI-MSn was utilized to study the stability and degradation of the two major but chemically unstable bioactive compounds hydroxysaffior yellow A and anhydrosaffior yellow B, in Safflower injection. The impact of light irradiation, temperature, and pH on the stability of these two compounds were studied. The results showed that hydroxysafflor yellow A and anhydrosafflor yellow B could degrade at high temperature （〉60 ℃） or extreme pHs （pH ≤ 3.0 or 〉7.0）, but not under light irradiation. The common degradation product was p-coumaric acid. Chemical structures of the other degradation products were characterized by LC-MS. Hypothetical degradation pathways were proposed. In addition, ADP-induced platelet aggregation tests showed that the degradation of anhydrosaffior yellow B could reduce the anticoagulation activities of Safflower injection. Our results suggest that temperature and pH are critically important for the preparation and storage of Safflower injection.
