To unambiguously identify spilled oils and to link them to the known sources are extremely important in settling ques-tions of environmental impact and legal liability. The fate and behavior of spilled oils in the env...To unambiguously identify spilled oils and to link them to the known sources are extremely important in settling ques-tions of environmental impact and legal liability. The fate and behavior of spilled oils in the environment depend on a number of physicochemical and biological factors. This paper presents the results regarding changes in chemical composition of light crude oil during simulated short-term weathering based on natural environmental conditions. The results show that the saturated hydrocarbons of the light crude oil mainly distribute between n-C8 and n-C23 and the most abundant n-alkanes are found in the n-C10 to n-C16. The main chemical components of the light crude oil are n-alkanes and isoprenoids. The aromatic compounds are subordinate chemical components. Under the conditions of the weathering simulation experiment,n-alkanes less than n-C12,toluene and 1,3-dimethyl ben-zene are lost after 1 d weathering,the n-C13,n-C14,naphthalene and 2-methyl-naphthalene are lost on the fifth day of weathering,and n-C15 alkane components show certain weatherproof capability. The ratios n-C17/pristane and n-C18/phytane are unaltered and can be used to identify the source of the light crude oil during the first 8 d of weathering. After 21 d,the ratio pristine/phytane can not pro-vide much information on the source of the spilled light crude oil. Triterpanes(m/z 191) as biomarker compounds of light crude oil are more valuable.展开更多
Objective： Evaluation of discrimination between two Mylabris Species based on HPLC fingerprinting andspectrum-antitumor effect relationship. Methods： In this study, a simple and efficient high-performance liquidchro...Objective： Evaluation of discrimination between two Mylabris Species based on HPLC fingerprinting andspectrum-antitumor effect relationship. Methods： In this study, a simple and efficient high-performance liquidchromatography （HPLC） method integrating with chemometric analysis and spectrum-antitumor effect relationship wasdeveloped for discrimination between two species of Mylabris： Mylabris phalerata Pallas （MP） and Mylabris cichoriiLinnaeus （MC）. Results： In the fingerprint analysis, 14 characteristic peaks were selected to assess the differencesbetween MP and MC using the similarity and pattern recognition analysis using PCA and OPLS-DA. The HPLCchromatograms of samples from 10 regions of China showed differences between MP and MC, and 7 characteristicchemical markers were found. In the spectrum-antitumor effect relationship analysis, 4 activity markers played a vitalrole in decreasing the IC50 and might be the antitumor components of Mylabris by grey relational analysis andmultivariate linear regression analysis. The chemometric analysis in combination with spectrum-effect relationshipresults indicated that peaks 2 （cytosine）, 4 （unknown） and 14 （unknown） were important differential markers fordistinguishing the two species of Mylabris. Conclusion： The method is applicable, credible and more efficient todiscriminate MP and MC, and will offer a new way for facilitating quality control of insect medicines.展开更多
文摘To unambiguously identify spilled oils and to link them to the known sources are extremely important in settling ques-tions of environmental impact and legal liability. The fate and behavior of spilled oils in the environment depend on a number of physicochemical and biological factors. This paper presents the results regarding changes in chemical composition of light crude oil during simulated short-term weathering based on natural environmental conditions. The results show that the saturated hydrocarbons of the light crude oil mainly distribute between n-C8 and n-C23 and the most abundant n-alkanes are found in the n-C10 to n-C16. The main chemical components of the light crude oil are n-alkanes and isoprenoids. The aromatic compounds are subordinate chemical components. Under the conditions of the weathering simulation experiment,n-alkanes less than n-C12,toluene and 1,3-dimethyl ben-zene are lost after 1 d weathering,the n-C13,n-C14,naphthalene and 2-methyl-naphthalene are lost on the fifth day of weathering,and n-C15 alkane components show certain weatherproof capability. The ratios n-C17/pristane and n-C18/phytane are unaltered and can be used to identify the source of the light crude oil during the first 8 d of weathering. After 21 d,the ratio pristine/phytane can not pro-vide much information on the source of the spilled light crude oil. Triterpanes(m/z 191) as biomarker compounds of light crude oil are more valuable.
基金Funding： This study was funded by the National Natural Science Foundation of China （81260488 and 81560669）, KeyLab Construction Project of the Educational Department of Guizhou Province （Project No. Guizhou EducationCooperation KY[2014]212） , Science Inovative Talent Team for Medicinal Insect Research and Development in Zunyi（Zunyi shi ke he 2015-40） and Modernization of Traditional Chinese Medicine in Guizhou Province high-tech researchand development projects （Qian ke he ZY 2012-2009）.
文摘Objective： Evaluation of discrimination between two Mylabris Species based on HPLC fingerprinting andspectrum-antitumor effect relationship. Methods： In this study, a simple and efficient high-performance liquidchromatography （HPLC） method integrating with chemometric analysis and spectrum-antitumor effect relationship wasdeveloped for discrimination between two species of Mylabris： Mylabris phalerata Pallas （MP） and Mylabris cichoriiLinnaeus （MC）. Results： In the fingerprint analysis, 14 characteristic peaks were selected to assess the differencesbetween MP and MC using the similarity and pattern recognition analysis using PCA and OPLS-DA. The HPLCchromatograms of samples from 10 regions of China showed differences between MP and MC, and 7 characteristicchemical markers were found. In the spectrum-antitumor effect relationship analysis, 4 activity markers played a vitalrole in decreasing the IC50 and might be the antitumor components of Mylabris by grey relational analysis andmultivariate linear regression analysis. The chemometric analysis in combination with spectrum-effect relationshipresults indicated that peaks 2 （cytosine）, 4 （unknown） and 14 （unknown） were important differential markers fordistinguishing the two species of Mylabris. Conclusion： The method is applicable, credible and more efficient todiscriminate MP and MC, and will offer a new way for facilitating quality control of insect medicines.
