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Objective The aim of this study was to determine the content of phthalate in disposable plastic tableware sold on Chengdu market,and to provide primary data for safety evaluation.Methods Sample selection was based on stratified sampling.Sixteen phthalate compounds were investigated in 60 disposable plastic tableware,divided into seven groups.The analysis was performed by gas chromatography-mass spectrometry (GC-MS).Results In this survey,diethyl phthalate,diisobutyl phthalate,dibutyl phthalate and diethylhexyl phthalate were detected,while the other 12 phthalate compound were not.The positive rates of the four detected phthalate were 6.7％ (4/60),10.0％ (6/60),46.7％ (28/60) and 28.3％ (17/60) respectively,and the highest concentrations were 10.3,6.4,7.2 and 65.6 mg/kg,respectively.Conclusion The observed level of detection rates and maximum concentrations were relatively high in this survey.In addition,some subgroups of PAEs that were not allowed to use in food contact materials were detected.Therefore,the migration in different food simulant would be analyzed in the next step for further health outcome assessment.
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Objective To study the determination method of total flavonoids in Gansu Astragali Radix and Hedysarum Polybotrys. Methods Calycosin glycosides etc. was selected as reference substances, comparison on the difference of absorption curves was done by ultraviolet spectroscopy and colorimetric method (NaNO2-Al(NO3)3-NaOH, AlCl3, Mg(Ac)2, NaOH, phosphomolybdic acid, HCl-Mg power). Results With colorimetric method, the maximum absorption wavelength of referrence and the test was inconsistent. The absorption peak shape was also different. With UV method, Calycosin glycosides in band Ⅱ (260 nm) showed a shoulder absorption. Astragali Radix and Hedysarum Polybotrys also showed characteristic shoulder absorptions in band Ⅱ with absorption wavelength at 263 nm and 265 nm. So the sample absorption wavelength is basically the same as that of the control sample. Conclusion Colorimetries usually used for determination of total flavonoids are not suitable for the comparison determination of Gansu Astragali Radix and Hedysarum Polybotrys. It is suitable for determining the contents of total flavonoids in samples by UV spectrophotometry at the band Ⅱ, which is the characteristic absorption band of isoflavone compound.
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<p><b>OBJECTIVE</b>To assess the quantitative risk of the polycyclic aromatic hydrocarbons (PAHs) dietary exposure from edible fats and oils in China.</p><p><b>METHODS</b>One hundred samples of edible fats and oils were collected from the supermarkets and the farmers markets in 11 provinces of China from December in 2013 to May in 2014. Then they were tested for EU15+1 PAHs (16 PAHs were controlled in priority by European Food Safety Authority) by two test methods which were QuECHERS-GC-MS-MS and GPC-HPLC-FLD. Data of PAHs concentration and edible fats and oils consumption which were from Chinese National Nutrition and Health Survey in 2002 were combined to evaluate carcinogenic risk of PAHs in edible fats and oils by the method of margin of exposure (MOE). In this process, we divided the population into 6 groups, namely male adults (older than 18 years old), female adults (older than 18), male youths (13-17), female youths (13-17), school-agers (6-12) and preschoolers (2-5), and thought carcinogenicity as the critical toxicity end point of PAHs. Two quantitative risk assessment methods, i.e. point assessment and probability assessment, were used to evaluate the dietary exposure and MOEs.</p><p><b>RESULTS</b>EU15+1 PAHs in one of 100 samples were not detected, other samples were polluted in different degrees; the detection rates were 3%-98% and the average contents were 0.26-3.26 μg/kg. The results of PAHs dietary exposure from both of point assessment and probability assessment were the same. The average exposures of PAH8 were as the following: male adults were 10.03 and (9.34 ± 12.61) ng·kg(-1)·d(-1)(The former was from point assessment and the latter from probability assessment, the same below), female adults were 9.95 and (9.60 ± 15.04) ng · kg(-1)·d (-1), male youths were 11.09 and (10.84 ± 16.54) ng·kg(-1)·d(-1), female youths were 10.06 and (9.58 ± 12.87) ng·kg(-1)·d(-1),school-agers were 15.29 and (15.62 ± 25.54) ng·kg(-1)·d(-1), preschoolers were 19.27 and (19.22 ± 28.91) ng·kg(-1)·d(-1). MOEs of mean and 50% exposure levels in different group of people were more than 10,000, while MOEs of 95% exposure levels in school-agers and preschoolers were less than 10,000.</p><p><b>CONCLUSION</b>For general consumers, the health risk of PAHs exposure is very low. However, for high-end consumers (95% exposure level) from the sensitive groups (school-ager and preschooler) has a potential health risk.</p>
Subject(s)
Adolescent , Adult , Child , Child, Preschool , Female , Humans , Male , Young Adult , China , Chromatography, High Pressure Liquid , Diet , Environmental Exposure , Fats , Chemistry , Food Safety , Plant Oils , Chemistry , Polycyclic Aromatic Hydrocarbons , Risk Assessment , Tandem Mass SpectrometryABSTRACT
Objective To study the effects of dietary estrogens genistein(GS)and zearalenone(ZEA)on apoptosis in-duced by estrogen depletion in PEO4cells.Methods The monolayer ovarian cancer cell line PEO4cells were cultured in DMEM medium containing10%bovine serum.Before the addition of the testing compounds the cells were washed in phosphate-buffered saline and the medium was displaced with a phenol red-free DMEM medium containing5%dextral charcoal-stripped FBS and the cells were cultured for5days in order to exhaust the estrogen stored in the cells,and then cells were divided into5groups,including solvent control group,estrogen control group,anti-estrogen control group and2experimental groups.After treatment the apoptotic features of the cells were observed by cellular morphology,DNA fragmentation and location and height of cell hypodiploid were indicated by flow cytometry.Results The typical characteristics of apoptosis in PEO4cells were observed after estrogen deletion and then disappeared following exposure of the PEO4cells to32?10 -9 mol/L and96?10 -9 mol/L ZEA for72hrs.32?10 -6 mol/L and96?10 -6 mol/L GS could significantly aggravate apoptosis in PEO4cells.Conclusion Zearalenone is a kind of mycoestrogen that has estrogenic activity to inhibit apoptosis in PEO4cells.Genistein is a kind of phytoestrogen that has anti-estrogen activity(tamoxifen-like)to promote apoptosis in PEO4cells with the high doses range.
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Objective: To explore the mechanisms of the effect of isoflavone in reducing prostate cancer incidence throught studying the effects of isoflavone on apoptosis in PC-3 cell. Methods: Prostate cancer cell PC-3 was grown in RPMI 1640 medium supplemented with 10% bovine serum and 10 000 U/ml of penicillin/streptomycin in an incubator maintained at 5% CO 2 95% air and 100% humidity at 37 ℃. The respective test compound was added in fresh medium and the control cell received only the vehicle (MDSO). Apoptosis of PC-3 cells was analyzed by cell morphology under light microscope, agarose gel electrophoresis and flow cytometry. Results: Exposure of PC-3 cell to 50 ?mol/L GS, 75 ?mol/L DA and 75 ?mol/L GL after 72 h, the cell morphology indicated typical features commonly used to define apoptosis; agarose gel electrophoresis demonstrated laddered electrophoretic profiles of oligonucleosomal DNA fragments indicative of apoptosis, and flow cytometric analysis revealed a hyperdiploid population in the tested cells. Conclusion: Isoflavones could induce apoptosis in prostate cancer cells PC-3 and it may be the main cause of their role in cancer inhibition.
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Objective: To explore the effect of curcumin on proliferation and apoptosis of TK6 human diploid lymphoblastoid cells.Methods: MTT colorometric assay, 3H-TdR incorporation, cell cycle analysis were used to evaluate the effect on proliferation, and morphology microstructure. Flow cytometry was used to detect the effect on apoptosis induction on TK6 cell.Results: Curcumin could inhibit proliferation by blocking transition from G0/G1 to S phase, induce apoptosis in TK6 cells. The effective dose for proliferation inhibition and apoptosis induction is 20 ?mol/L.Conclusion: Apoptosis induction is one of important mechanisms for anti-mutagenic, anti-tumor action of curcumin.
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8 ?mol/L)was markedly restrained. Zearalenone, like estradiol, could markedly increase the proliferation of MCF-7 cells. The effects were time-dependent and dose-dependent. Conclusion: The tested phytoestrogens are biologically active, and they can differently affect the proliferation of human breast cancer cells in vitro. These data suggest that genistein may have preventive and therapeutic applications against breast tumors.
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The effects of high erucic acid rapeseed oil (HER) on fatty acid oxidation in rat livers compared with low erucic acid rapeseed oil (LER) were studied. Weanling male SD rats were fed on 20% (% by weight, similarly hereinbelow) HER or LER diet for a week or 4 weeks, or 5% HER diet for 4 weeks. The hepatic capacity for oxidation of butyric acid and palmitic acid was determined by titrating the acetone produced by the fatty acid oxidation. The results showed that feeding HER to rats led to an increse in weight of liver and the extent of this increase was positively correlated to the intake of erucic acid (C22:1, n-9 cis). Feeding HER reduced the hepatic oxidation capacity for palmitic acid, notably in 20% HER (1 wk) group. Feeding LER had not shown this effect,indicating that erucic acid plays an important role in the toxicity of rapeseed oil. In the present study it was not found that the hepatic oxidation capacity for butyric acid was influenced by the intake of HER. Therefore, we considered that the inhibitory effect of HER on oxidation of long-chain fatty acids probably resulted from that the incorporation of erucic acid into mitocho-ndrial membranes interfered with the fatty acyl-CoA transfering system on the membranes, leading the fatty acyl-CoA to be unable to enter the mitochondria and to be oxidized there, but not from that the B-oxidation system in mitochondria was directly inhibited.
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This paper reports a study regarding the verity of the hypocholestero-lemic effect of konjac-polysaccharide. The konnyaku powder (KP) used in this study was prepared and refined from the tubers of Amorphophallus ko-njac K. Koch and contained 84.8% of glucomannan. Male and female Spra-ue-Dawley rats aged 5 weeks were divided into 5 groups and fed on normal basal diet, hypercholesterolemic diet (control diet) and 3 test diets (i.e. KP was added to the control diet at a dosage of 2.5%, 5% or 10%) respe- ctively, for 12 weeks.The results obtained from this study showed that KP could markedly lower the level of the cholesterol in sera and livers of rats feeding hyper-cholesterolemic diets. At the end of the 4th week of the feeding experiment, the serum cholesterol level of the 5% and the 10% KP groups, and the liver cholesterol level of the 10% KP group were shown to be significantly lower than those of the control group. At the end of the 12th week, serum cholesterol levels of all the 3 KP groups were found to be lowered to the level of the normal group and so did the liver cholesterol level of the 10% KP group. The lipotropic (anticholesteatosis) effect of KP was also confirmed by the hepatic histopathological examination. Besides the hypocholest-eroletmic eftect, KP diets can also increase the bulk of stool. Finally, there were not any harmful effects on the absorption and utilization of Ca, Fe, Zn and Cu being found.
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Objective: To characterize the effects of genistein (GS) on tumor-associated gene expression in MCF-7 cells and to explore the mechanisms. Method: MCF-7 cells were treated with GS (75?10-6 mol/L) or with vehicle (0.1% ethanol, EtOH) for 72 h. The cells were collected and total RNA was extracted, marked by two different fluorescence dyes (Cy3 and Cy5) using reverse transcriptional reaction, respectively. The derived cRNA was hybridized to human tumor-associated microarrays. Data were processed using the Scan Array 3000 and ontological analysis was performed using the Ima Gene 3.0 software. Results: At 72 h, 18 transcripts were downregulated compared to EtOH vehicle control by greater than 2- fold and 4 were upregulated by less than 0.5-fold. The predominant ontological groupings were oncogenes, cell proliferation, apoptosis, and estrogen-regulation genes. Conclusion: GS treatment is associated with significant changes in gene expression in several functional categories in MCF-7 cells, and this might account for the role of genistein in prevention of breast cancer.
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Objective: This study was designed to investigate the molecular mechanisms of proliferation and apoptosis by genistein and zearalenone through regulation of mRNA and protein expression of PCNA, bcl-2 and bax in breast cancer MCF-7 cells. Methods: The cells were maintained in DMEM medium with 10% fetal bovine serum. Five days before the beginning of experiments, the cells were seeded in phenol red-free DMEM medium containing 5% charcoal dextran–treated FBS. The cells were harvested and seeded in 6-well culture plates or in 75 ml flacks. After various concentrations of genistein and zearalenone treatments for 72 h, the cells were harvested and mRNA and protein expression of proliferation cell nuclear antigen(PCNA), bcl-2 and bax were detected by reverse transcription-polymerase chain reaction and immunohistochemistry, respectively. Results: At the concentration of 75 ?mol/L, GS could significantly down-regulate bcl-2 and PCNA mRNA expression and up-regulate bax mRNA expression, and zearalenone indicated an opposite result. These results were further confirmed by following immunohistochemistry. Conclusion:PCNA, bcl-2 and bax pathway might be involved in cell proliferation and apoptosis events regulated by dietary estrogens genistein and zearalenone in breast cancer MCF-7 cells.