Effects Of Heavy Metals On Chemical Constituents In Chrysanthemum Morifolium Ramat And Study On Pesticide Residue Enrichment

As the natural conditions and color,aroma,taste,shape of Chrysanthemum than other Chrysanthemum more high-quality,taste mellow and sweet,Chrysanthemum tea is the best one.Also because of the high medicinal value of Chrysanthemum,eating Chrysanthemum can increase the health of the body,so has been praised and used by the public since ancient times.However,the heavy metal pollution and pesticide residues in Chrysanthemum affect the quality of Chrysanthemum and harm the health of human body.Therefore,this experiment adopted the way of Pot experiment in greenhouse to study the quality change of Chrysanthemum caused by heavy metal pollution,two kinds of heavy metal contaminated soils with different alkalinity were collected and three kinds of passivators were added to the soils in order to understand the effects of different passivators on the quality of Chrysanthemum morifolium Ramat.For the study of pesticide residue in Chrysanthemum,the samples were collected after 2h,3d and 7d after spraying normal dose and 1.5 times IMIDACLOPRID,in order to understand the regularity of pesticide residues in Chrysanthemum morifolium Ramat.The results are as follows:(1)A standard curve for the determination of heavy metals in Chrysanthemum morifolium Ramat and soil,a standard curve for the determination of chemical components in Chrysanthemum morifolium Ramat and a standard curve for Imidacloprid pesticide were established,the R~2 standard curves for the determination of heavy metals in Chrysanthemum morifolium Ramat were 0.9999,0.9997 and 0.9992,respectively.The R~2 of the standard curve of cadmium in Chrysanthemum morifolium Ramat and soil was 0.9955,and the R~2 of the standard curve of lead,arsenic and mercury in soil were 0.9977,0.9998 and 0.998,respectively.For the determination of chemical constituents in Chrysanthemum morifolium Ramat,the standard curve of chlorogenic acid was R~2=0.9998,the standard curve of Luteolin was R~2=0.9995,and the standard curve of isochlorogenic acid a was R~2=0.9996.The R~2 of imidacloprid standard curve was 0.9991 for the determination of pesticide residues in Chrysanthemum morifolium Ramat.The above shows that the standard curve is well linear.(2)Under the condition of adding modified humic acid,conditioning agent and biochar passivating agent to cadmium contaminated soil,When the planting soil pH=7.24,the range of heavy metal cadmium in Chrysanthemum morifolium Ramat is 1.61%?53.15%,when the planting soil pH=7.66,the range of heavy metal cadmium in Chrysanthemum morifolium Ramat is 10.61%?61.72%.The addition of three passivating agents in the two pH soil conditions showed that the content of heavy metal cadmium in Chrysanthemum morifolium Ramat could be reduced,and the order of the reduction ability of heavy metal cadmium in Chrysanthemum morifolium Ramat was as follows:biochar,conditioner and modified humic acid.Taking four kinds of heavy metals in Hangbai as indicators,principal component analysis was carried out to comprehensively evaluate the safety of Chrysanthemum morifolium Ramat on heavy metal pollution.According to the comprehensive score of principal component analysis,the order of safety from high to low was J-2 group,J-1 group,J-3 group,J-4 group,S-1 group,S-2 group,S-4 group and S-3 group.(S,J:Means Soil pH=7.24,pH=7.66;1,2,3,4:means 4 treatment groups namely 1 is blank treatment group,2,3,4 is passivator added in soil is:modified humic acid,conditioner,biological carbon.The following is the same).(3)In terms of the quality of Chrysanthemum morifolium Ramat,For the chlorogenic acid quality index,The content of chlorogenic acid in the eight groups ranged from 0.0505%to0.2044%,The content of luteolin ranged from 0.0681%to 0.1824%,and the content of isochlorogenic acid A ranged from 0.0760%to 0.2487%.Taking three quality indexes of Chrysanthemum morifolium Ramat sinensis as indexes,principal component analysis was carried out to comprehensively evaluate the quality of Chrysanthemum morifolium Ramat sinensis sinensis.The results showed that the order of quality of Chrysanthemum morifolium Ramat sinensis sinensis in eight groups from high to low was as follows:S-4 group,J-3 group,J-2 group,S-3 group,S-2 group,S-1 group,J-4 group,J-1 group.(4)When ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS)was used to detect pesticide residues in Chrysanthemum morifolium Ramat,imidacloprid residues were not detected in the roots and stems of Chrysanthemum morifolium Ramat.The results showed that Imidacloprid pesticide residues in leaves were significantly higher than that in flowers at 2h,3d and 7d after spraying,and the extent of pesticide reduction in flowers was greater than that in leaves at 7d after spraying,this suggests that the leaves absorb pesticides more easily and degrade less quickly than the flowers.