Seven polycyclic aromatic hydrocarbons （PAHs） in atmospheric particulates were determinated by high performance liquid chromatography （HPLC） with fluorescence detector using direction injection and an on-line enri...Seven polycyclic aromatic hydrocarbons （PAHs） in atmospheric particulates were determinated by high performance liquid chromatography （HPLC） with fluorescence detector using direction injection and an on-line enrichment trap column. The method simplified the sample pretreatment, saved time and increased the efficiency. With the on-line trap column, PAHs were separated availably even underground injecting 1.0 ml sample with relatively high column efficiency. The recoveries of the seven PAHs were from 85% to 120% for spiked atmospheric particulate sample. The limit of detection was 15.3-39.6 ng/L （S/N=3.3）. There were good linear correlations between the peak areas and concentrations of the seven kinds of PAHs in the range of 1-50 ng/ml with the correlation coefficients over 0.9970. Furthermore, it also indicated that the method is available to determine PAHs in atmospheric particulates well.展开更多
Astrapterocarpan(AP) is a bioactive constituent of Astragali Radix and was selected as a model compound for investigating the in vitro metabolism of pterocarpans in this study. Its in vitro metabolism was conducted by...Astrapterocarpan(AP) is a bioactive constituent of Astragali Radix and was selected as a model compound for investigating the in vitro metabolism of pterocarpans in this study. Its in vitro metabolism was conducted by incubation with rat hepatic 9000 g supernatant(S9) in the presence of an NADPH-generating system. At first, four compounds were isolated and their structures were elucidated as 6 a-hydroxy-AP(M1), astrametabolin I [M2, 1 a-hydroxy-9, 10-dimethoxy-pterocarp-1(2), 4-diene-3-one], 9-demethyl-AP(M3, nissolin) and 4-methoxy-astraisoflavan(M4, 7, 2’-dihydroxy-4, 3’, 4’-trimethoxy-isoflavan) on the basis of NMR data, respectively. Among them, M1, M2 and M4 were new compounds. Next, the metabolite profile of AP in rat hepatic S9 was obtained via HPLC-DAD-ESI-IT-TOF-MSn, and 40 new metabolites were tentatively identified. These newly identified metabolites included 9 monohydroxylated metabolites, 1 demethylated metabolite, 7 demethylated and monohydroxylated metabolites, 4 dihydroxylated metabolites, 1 hydration metabolite, 1 didemethylated metabolite, 2 glucosylated metabolites, 1 monohydroxylated and dehydrogenated metabolite, 2 monohydroxylated and demethylated and dehydrogenated metabolites, 2 dimerized metabolites, 3 dimerized and monohydroxylated metabolites, 2 dimerized and didemethylated metabolites, and 5 dimerized and demethylated metabolites. Finally, the major metabolic reactions of AP in rat hepatic S9 were summarized and found to be hydroxylation, demethylation, dimerization, hydration, and dehydrogenation. More importantly, the biotransformation from AP to M2 and the dimerization of AP by incubation with hepatic S9 were reported for the first time. In conclusion, this is the first report on the metabolism of a pure pterocarpan in animal tissues, and these findings will provide a solid basis for further studies on the metabolism of other pterocarpans.展开更多
基金Project supported by the National Natural Science Foundation of China (No.20437020)Major Research Program of Chinese Academy of Sciences (No.KZCX3-SW-432).
文摘Seven polycyclic aromatic hydrocarbons （PAHs） in atmospheric particulates were determinated by high performance liquid chromatography （HPLC） with fluorescence detector using direction injection and an on-line enrichment trap column. The method simplified the sample pretreatment, saved time and increased the efficiency. With the on-line trap column, PAHs were separated availably even underground injecting 1.0 ml sample with relatively high column efficiency. The recoveries of the seven PAHs were from 85% to 120% for spiked atmospheric particulate sample. The limit of detection was 15.3-39.6 ng/L （S/N=3.3）. There were good linear correlations between the peak areas and concentrations of the seven kinds of PAHs in the range of 1-50 ng/ml with the correlation coefficients over 0.9970. Furthermore, it also indicated that the method is available to determine PAHs in atmospheric particulates well.
基金supported by the National Natural Science Foundation of China(No.81673595)China Postdoctoral Science Foundation(Nos.20080430293 and 200902040)Guizhou Natural Science Foundation(No.QIANKEHE [2018]1071)
文摘Astrapterocarpan(AP) is a bioactive constituent of Astragali Radix and was selected as a model compound for investigating the in vitro metabolism of pterocarpans in this study. Its in vitro metabolism was conducted by incubation with rat hepatic 9000 g supernatant(S9) in the presence of an NADPH-generating system. At first, four compounds were isolated and their structures were elucidated as 6 a-hydroxy-AP(M1), astrametabolin I [M2, 1 a-hydroxy-9, 10-dimethoxy-pterocarp-1(2), 4-diene-3-one], 9-demethyl-AP(M3, nissolin) and 4-methoxy-astraisoflavan(M4, 7, 2’-dihydroxy-4, 3’, 4’-trimethoxy-isoflavan) on the basis of NMR data, respectively. Among them, M1, M2 and M4 were new compounds. Next, the metabolite profile of AP in rat hepatic S9 was obtained via HPLC-DAD-ESI-IT-TOF-MSn, and 40 new metabolites were tentatively identified. These newly identified metabolites included 9 monohydroxylated metabolites, 1 demethylated metabolite, 7 demethylated and monohydroxylated metabolites, 4 dihydroxylated metabolites, 1 hydration metabolite, 1 didemethylated metabolite, 2 glucosylated metabolites, 1 monohydroxylated and dehydrogenated metabolite, 2 monohydroxylated and demethylated and dehydrogenated metabolites, 2 dimerized metabolites, 3 dimerized and monohydroxylated metabolites, 2 dimerized and didemethylated metabolites, and 5 dimerized and demethylated metabolites. Finally, the major metabolic reactions of AP in rat hepatic S9 were summarized and found to be hydroxylation, demethylation, dimerization, hydration, and dehydrogenation. More importantly, the biotransformation from AP to M2 and the dimerization of AP by incubation with hepatic S9 were reported for the first time. In conclusion, this is the first report on the metabolism of a pure pterocarpan in animal tissues, and these findings will provide a solid basis for further studies on the metabolism of other pterocarpans.
