No abstract available.
Aflatoxin B1* ; Aflatoxins*

No abstract available.
Aflatoxin B1* ; Aflatoxins* ; Enzyme-Linked Immunosorbent Assay* ; Humans*

During 2011~2013, a total of 729 samples for 19 types of medicinal plant were collected from Seoulyekryungsi in Seoul, Korea, and investigated for the presence of aflatoxins. The samples were analyzed using immunoaffinity column cleanup and high-performance liquid chromatography coupled to a fluorescence detector after post-column derivatization. Aflatoxins were found in 124 out of the 729 analyzed samples: 65 containing aflatoxin B1 (AFB1), 24 with aflatoxin B2 (AFB2), 15 with aflatoxin G1 (AFG1), and 20 samples with aflatoxin G2 (AFG2). The ranges for positive samples were 0.1~404.7 microg/kg for AFB1, 0.1~10.0 microg/kg for AFB2, 0.1~635.3 microg/kg for AFG1, 0.1~182.5 microg/kg for AFG2, and 0.1~1,043.9 microg/kg for total aflatoxins. Most of the medicinal plant samples (721, 98.9%) were below legal limits, but 8 samples exceeded the legal limits of 10 and 15 microg/kg established by the Korean standard for AFB1 and total aflatoxins (the sum of AFB1, AFB2, AFG1 and AFG2), respectively.
Aflatoxin B1 ; Aflatoxins* ; Chromatography, Liquid ; Fluorescence ; Incidence* ; Korea ; Plants, Medicinal* ; Seoul

Lactobacillus casei KC-324 was tested for its ability to inhibit aflatoxin production and mycelial growth of Aspergillus flavus ATCC 15517 in liquid culture. Aflatoxin B1 biosynthesis and mycelial growth were inhibited in both simultaneous culture and individual antagonism assays,suggesting that the inhibitory activity was due to extracellular metabolites produced in cell-free supernatant fluids of the cultured broth of L. casei KC-324. In cell-free supernatant fluids of all media tested,deMan,Rogosa and Sharpe broth,potato dextrose broth,and Czapek-Dox broth + 1% yeast extract showed higher antiaflatoxigenic activity. In these case, fungal growths, however, was not affected as measured by mycelial dry weight. The antiaflatoxigenic metabolites from L. casei KC-324 were produced over wide range of temperatures between 25degrees C and 37degrees C. However, these metabolites were not thermostable since the inhibitory activity of the supernatant was inactivated within 30 minutes at 100degrees C and 121degrees C. The inhibitory activity was not influenced by changing pH of supernatant between 4 and 10. However,the antiaflatoxigenic activity was slightly reduced at pH 10.
Aflatoxin B1 ; Aflatoxins* ; Aspergillus flavus* ; Glucose ; Hydrogen-Ion Concentration ; Lactobacillus casei* ; Yeasts

Using tree shrew as an animal model, our previous studies have demonstrated synergistic effects of aflatoxin B-1 (AFB(1)) and human hepatitis B virus (HHBV) in the induction of hepatocellular carcinoma (HCC). In the present study, we have examined expression of p53 gene in HCCs induced by AFB(1) with or without HHBV infection in tree shrews. Avidin-biotin-peroxidase complex immunohistochemical method with human p53-CM1 polyclonal antibody has been used to detect p53 expression in serial sections of paraffin-embedded liver and HCC tissues. Five out of 9 animals with HCCs (55.6%) induced by AFB(1) with HHBV infection and 2/3 animals with HCCs (66.7%) induced by AFB(1) alone expressed the p53 protein. Out of 18 HCCs examined, expression of p53 protein was observed in 9/10 moderately and poorly differentiated HCCs (0/8). None of the well differentiated HCCs (0/8) expressed p53 (0%). Similarly, no p53 expression was observed in either non-tumorous or hyperplastic liver tissues or nodules. These results suggest that p53 expression associated with p53 mutation is a late event occurring probably during tumor progression in AFB(1) and HHBV induced hepatocarcinogenesis in the tree shrew. This report is the first example of an experimental animal model where combination of human HBV and AFB(1)-induced HCCs demonstrate p53 expression.
Aflatoxin B1* ; Aflatoxins* ; Animals ; Carcinoma, Hepatocellular* ; Genes, p53* ; Hepatitis B virus* ; Hepatitis B* ; Hepatitis* ; Humans* ; Liver ; Models, Animal ; Tupaiidae*

AIMTo compare the post-column derivatization technique (IAC-PCD-HPLC) for the determination of aflatoxins B1, B2, G1 and G2 and the rapid procedure with fluorometric analysis (SFB) for the determination of total aflatoxins.

METHODSThe method of post-column derivatization with bromine by HPLC consisted of extraction of the sample with MeOH-H2O (70:30) followed by clean-up of the extracts with immunoaffinity columns and finally, HPLC determination with fluorescence detection. Aflatoxins B1 and G1 were determined as their bromine derivatives, produced in an on-line post-column derivatization system. In SFB method, samples were ground and extracted with methanol-water (70:30). A portion of the extract was cleaned up by passage through a immunoaffinity column, One mL of purified extract was derivatized with a bromine reagent, and fluorescence of the solution was immediately quantified with a calibrated fluorometer containing a broad wavelength pulsed xenon light source.

RESULTSIn IAC-HPLC method, the overall average recoveries for three different medicinal herbs spiked at levels of 1.3 and 2.6 ng x g(-1) of total aflatoxins ranged from 93% to 97%. The detection limit was 0. 06 microg x kg(-1) for both G2 and B2 and 0.20 microg x kg(-1) for both G1 and B1, based on a signal/noise 3:1 and the precision (within-laboratory relative standard deviation) ranged from 0.8% to 1.4%. Each of aflatoxins B1, B2, G1 and G2 in 39 kind medicinal materials were determined by IAC-PCD-HPLC, and the total aflatoxins were determined by SFB.

CONCLUSIONThe SFB method is not the suitable method for the determination of total aflatoxins in medicinal herbs and plant extracts.

Aflatoxin B1 ; analysis ; Aflatoxins ; analysis ; Bromine ; Chromatography, High Pressure Liquid ; methods ; Codonopsis ; chemistry ; Drugs, Chinese Herbal ; chemistry ; Plants, Medicinal ; chemistry ; Prunus ; chemistry ; Spectrometry, Fluorescence ; methods

OBJECTIVETo develop a new and accurate method to quantify aflatoxins in medicinal herbs.

METHODThis method consists of sample extraction by using MeOH-H2O (7:3), followed by clean-up with an immunoaffinity column, and finally HPLC determination with fluorescence detection. Aflatoxins B1 and G1 are determined as their bromine derivatives, produced in an on-line post-column derivatization system.

RESULTThe overall average recoveries for different medicinal herbs spiked at two levels of standards were from 90.4% to 99.7%. The detection limit was 0.06 microg x kg(-1) for aflatoxins G2 and B2, and 0.20 microg x kg(-1) for aflatoxins G1 and B1.

CONCLUSIONThe use of immunoaffinity column provides excellent cleanup of interfering substances. The method has been applied successfully to analyze 96 natural drugs.

Aflatoxin B1 ; analysis ; Aflatoxins ; analysis ; Chromatography, Affinity ; Chromatography, High Pressure Liquid ; methods ; Codonopsis ; chemistry ; Drugs, Chinese Herbal ; chemistry ; Plants, Medicinal ; chemistry ; Prunus ; chemistry

As the dilution procedure was applied, a simple, rapid and cost-effective high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determination of aflatoxin B1, B2, G1, and G2 was successfully by performed in a total 83 samples of 10 traditional Chinese medicines (TCMs), which were collected from 5 different hospital pharmacies and 5 different medical stores in Guangzhou city. Matrix effects of these 10 TCMs were ranged from 80.23% to 115.5% in low, intermediate and high concentration levels, indicating that the negative effect was overcome in this study. Meanwhile, the analysis method was proved to be stable and reliable during the whole analysis using Semen Armeniacae Amarum spiked 3 concentration levels of standard solution as quality control samples and the RSD < 6.6% was obtained. The contamination levels of 83 investigated samples were 13.89% and 17.02% in hospital pharmacies and medical stores, respectively. The result was presented to provide relevant reference and supplement to those researchers in TCMs analysis and screening.
Aflatoxin B1 ; analysis ; Aflatoxins ; analysis ; Chromatography, High Pressure Liquid ; methods ; Drug Contamination ; Medicine, Chinese Traditional ; Quality Control ; Tandem Mass Spectrometry ; methods

OBJECTIVES: Aflatoxin M1 (AFM1)-contaminated dairy products pose serious human health risks, causing liver and renal failure if consumed. They are also related to decreased milk and egg production in infected animals. This study investigated the AFM1 contamination levels in cheeses sold in Isfahan province, Iran, by enzyme-linked immunosorbent assay (ELISA). METHODS: A total of 100 white cheese samples were randomly collected from supermarkets in Isfahan province and after extraction using dichloromethane were prepared for the ELISA. RESULTS: Of the 100 samples, 52 (52%) were contaminated by AFM1, at levels ranging from 50.2 to 424.4 ng/kg. The remaining 48% of the samples had undetectable AFM1 levels (< 50 ng/kg). Based on the standard limit set by the European Commission and Iran, 8% (8/100) of the AFM1-positive samples (with concentrations between 250.2 and 424.4 ng/kg) had levels higher than the permissible value of 250 ng/kg. CONCLUSION: Although the percentage of cheese samples in Isfahan province with AFM1 levels exceeding the national permissible limit was low, the examination of cheeses and the milk used for their production is nevertheless important for ensuring public health. Furthermore, optimum storage conditions of animal feed should be ensured, and livestock nutrition must be monitored for the presence of AFM1 and other aflatoxins.
Aflatoxin M1* ; Aflatoxins* ; Animal Feed ; Animals ; Cheese* ; Dairy Products ; Enzyme-Linked Immunosorbent Assay ; Humans ; Iran* ; Liver ; Livestock ; Methylene Chloride ; Milk ; Ovum ; Public Health ; Renal Insufficiency

243 food samples (maize, ground nut and its products) were assessed. 90% of sample well preserved at home were contaminated with aflatoxine. The contaminant level passed the standard limit (8.3% as regulated by the Ministry of Health). The main measure to overcome aflatoxine contamination on food was considered GAP (good agricultural production) in all stages of agricultural production and preservation.
Aflatoxins ; Food ; Food Preservation