| Macro-fungi contains high levels of essential elements without radioactive elements, and it is one of the most important food for human beings. Medicinal macro-fungi has a long history of use as traditional medicine. It also widely used as folk medicines by western countries. Wild medicinal(or edible) fungi can accumulate many essential elements, such as Ca, Cu, Fe, K, Mg, Mn, Na, P, Zn and so on, but some other species can enrich toxic elements, such as As, Cd, Hg, Pb. It is necessary to research the chemometric characteristics of medicinal fungi elements.Wolfiporia extensa(Peck) Ginns is a popular fungus of the family Polyporaceae. The peel and flesh of W. extensa can be used as medicine. W. extensa has attracted considerable attention recently due to the various physiological properties, such as sedative, stomachic and diuretic in TCMs for thousands of years. It has not been studied before about the accumulation trend of element content which from different part of W. extensa. Yunnan is the major production area of W. extensa in China. It also urgent to be further studied whether there were difference for the element content of W. extensa which collected from different sites or from different growing environment. In this study, atomic fluorescence spectrometry(AFS), inductively coupled plasma atomic emission spectrometry(ICP-AES), inductively coupled plasma mass spectrometer(ICP-MS) combined with chemometrics were used for mineral element analyzed, and health risk assessment. The result provided reasonable foundation for exploitation and consumption security.This dissertation is composed of five sections. Sections 1 including chapter 1 is about the determination and analysis of the element concentration in W. extensa from difference sites. Sections 2 including chapter 2 and chapter 3 is about chemometric evaluation of mineral elements content in wild and cultivated W. extensa. Sections 3 including chapter 4 is about the health risk assessment of arsenic, cadmium and lead in flesh from W. extensa. Sections 4 including chapter 5 is about the determination and multivariate statistical analysis of the elements content from W. extensa.Eighteen macro and trace elements in both flesh and peel of W. extensa from seven sites of Yunnan province in China were determined by ICP-MS. The results of this survey indicate that mineral compositions in peel were higher than in flesh. In peel, the contents of investigated trace metals in mushroom samples were found to be in the range of 1660-13400 mg/Kg d.m for Fe, 29.6-710 mg/Kg d.m for Mn. The mean contents of Cr, Cu, Rb, V, and Zn in peel were between 10 and 20 mg/Kg d.m. Followed by As, Co, Li, Ni, Pb, Se, and Sr with mean between 1 and 10 mg/Kg d.m, while Ag, Cd, and Cs were <1 mg/Kg d.m. In flesh, the concentration of Fe were in the range of 54.4-902 mg/Kg d.m, and 1.55-48.6 mg/Kg d.m for Mn. Followed by Ba, Cu, Rb and Zn were between 1 and 10 mg/Kg d.m, while Ag, As, Cd, Co, Cr, Cs, Li, Ni, Pb, Se, Sr and V were <1 mg/Kg.Fifteen elements Li, Mg, K, Ca, V, Cr, Mn, Fe, Cu, Zn, As, Rb, Sr, Cs, and Pb in the sclerotia W. extensa from 28 sites of Yunnan provience were determined by ICP-MS after microwave digestion. The results indicated that mineral wild W. extensa collected from Yunnan contains many kind of mineral elements. The concentration level of Ca, K, Mg, and Fe are the highest, and the toxic element As and Pb level are below the limit, which permitted by GB 2762-2012 and FAO/WHO. The results of PCA indicated that 4 principal components were chosen to examine the dataset which can explain 77.55% of the total variance. V, Fe, Li, As, Cs, Cr, Pb, Sr, Ca, and Mn were inferred to be characteristic elements in wild W. extensa. The result of CA for the samples indicate that there are significant differences between mineral elements mainly because the content level in wild W. extensa are greatly influenced by the topography and climate characteristics of Yunnan provience.Twenty mineral elements from the flesh of W. extensa were determined by ICP-MS. The concentration of K is the highest, followed by Ca, Mg, Fe, and Ba, Cu, Rb, Zn. The content of Co, Cr, Ni, Pb, Sr, V, Ag, As, Cd, Cs, Li in W. extensa is the lowest. The results of PCA show that 5 principal components were chosen to examine the dataset which can explain 88.2% of the total variance. The wild samples and cultivated samples could be distinguished through partial least squares-discriminant analysis(PLS-DA).This chapter aimed at providing and evaluating data on As, Cd and Pb contents of sclerotia of W. extensa collected across Yunnan in China. For the present research, As, Cd, and Pb concentration in sclerotia of wild and cultivated W. extensa were determined by ICP-MS. The results showed that As, Cd, and Pb contents were below the limits promulgated by WHO with the range of 5.27-161, 1.51-42.1 and from trace to 634 ng/g dry matter. Calculated hazard quotient(HQ) and hazard index(HI) were used to evaluate the noncarcinogenic health risk from individual and combined metals via daily consumption of 50 g of sclerotia. Both HQs and HI through consumption of sclerotia were below 1. Obviously, weekly consumption of sclerotia at the indicated doses poses no significant health risk to a normal adult.Eleven elements concentrations(As, Ba, Cd, Cu, Fe, Mn, Ni, Pb, Se, Sr and Zn) from the medicinal and edible fungus W. extensa were determined by using AFS(for As and Se) and ICP-AES(for Ba, Cd, Cu, Fe, Mn, Ni, Pb, Sr and Zn). The recovery rates of standard addition ranged from 98.24% to 111.8% with the correlation coefficients were all above 0.999. The As(0.009-0.41 mg/Kgdw), Cd(0-0.266 mg/Kg dw) and Pb(0-2.6 mg/Kg dw) contents were below the permissible limits in food which were promulgated by WHO. The result of PCA indicated that the samples from same sites can cluster together, this may because the element concentration are similar. |
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