Ochratoxin A (OTA) is a toxic secondary metabolite mainly produced by Aspergillus and Penicillium species, existing in a variety of foodstuffs and Chinese medicines. OTA is difficult to be detected in practice because of the characteristics such as trace amounts, toxicity, existing in complex matrices. In the numerous detection technologies, colloidal gold chromatographic techniques are highly sensitive, specific, cost-effective and user-friendly, and are being used increasingly for OTA screening. Recently, with the development of aptamer technology and its application in chromatographic technique, a newly colloidal gold aptamer chromatographic technique has been developed. This review elaborates the structures and principles of both traditional and newly colloidal gold chromatographic techniques, focuses on newly colloidal gold aptamer chromatographic technique, summarizes and compares their use in rapid detection of OTA. Finally, in order to provide a reference for better research of related work, the development trends of this novel technique are prospected.
Base Sequence ; Chromatography ; methods ; Gold Colloid ; chemistry ; Molecular Sequence Data ; Ochratoxins ; analysis

OBJECTIVETo determine the fungal populations in seven ochratoxin A contaminated root herbs in Jiangxi province, and investigate the mycoflora associated with mycotoxin contamination in the root herbs.

METHODSingle spore isolation was used to obtain the strains from root herb's surface. Fungi were identified according to morphology and molecular evidence.

RESULTSeventeen fungal species belonged to six isolated genera, nine species of Penicillium, three species of Aspergillus, two species of Fusarium and three other species were identified.

CONCLUSIONFungal contamination of root herbs demands urgent attention, ochratoxin A producing fungi possess specific distribution on herbs.

Drug Contamination ; Drugs, Chinese Herbal ; standards ; Fungi ; isolation & purification ; Ochratoxins ; analysis ; Plant Roots ; microbiology

OBJECTIVETo establish a method for the content determination of 5-methylmellein, 5-hydroxymellein, 5-carboxylmellein and genistein in Wuling capsules simultaneously by HPLC.

METHODFour components were determined by HPLC on a Kromasil KR100-5C18 column (4.6 mm x 250 mm, 5 microm) with acetonitrile and 0. 2% phosphoric acid as mobile phase in a gradient elution. The flow rate was 1.0 mL x m min(-1), and the column temperature was set at 30 degrees C.

RESULT5-hydroxymellein showed a good linear relationship at the range of 7.86-157.2 ng, the average recovery was 101.0% with RSD 1.3%. 5-carboxylmellein showed a good linear relationship at the range of 9.57-191.4 ng, the average recovery was 98.6% with RSD 1.5%. Genistein showed a good linear relationship at the range of 28.80-576.0 ng, the average recovery was 98.6% with RSD 1.8%. 5-methylmellein showed a good linear relationship at the range of 21.46-429.2 ng, the average recovery was 99.2% with RSD 1.8%.

CONCLUSIONThe established method is feasible and the repeatability is good. The method can be used for quality control of Wuling capsules.

Capsules ; Chromatography, High Pressure Liquid ; methods ; Drugs, Chinese Herbal ; chemistry ; Genistein ; analysis ; Ochratoxins ; analysis ; chemistry ; Reproducibility of Results

Fumonisin B1 (FB1) is a carcinogenic mycotoxin found in commodities such as corn and corn-originated products. An aptamer-based method for detection of FB1 was developed using the fluorescent dye PicoGreen, which can recognize and bind double-stranded DNA. A peak fluorescence of PicoGreen was obtained in 15 min in the presence of FB1 aptamer, which formed a double-stranded hybridizer DNA with its complementary strand. The excitation and emission wavelengths for PicoGreen detection were 480 nm and 520 nm, respectively. The sensitivity of this aptamer/PicoGreen-based method was 0.1 μg/L. This method showed a good linearity for FB1 concentration ranging from 0.1 to 1 μg/L. The entire detection procedure for FB1 could be completed within 40 min. No cross reactions were observed with any other mycotoxins against aflatoxin B1, ochratoxin A, citrinin and zearalenone, demonstrating high specificity towards FB1 aptamer. Agreement between commercial, antibody-based enzyme-linked immunosorbent assay (ELISA) kit and aptamer method was excellent with a kappa value of 0.857. Taken together, this aptamer/PicoGreen-based method is more cost-effective, time-saving and useful than ELISA for detection of FB1.
Aflatoxin B1 ; Enzyme-Linked Immunosorbent Assay ; Fluorescence ; Fluorescent Dyes ; chemistry ; Fumonisins ; analysis ; Mycotoxins ; analysis ; Ochratoxins ; Organic Chemicals ; chemistry ; Staining and Labeling ; Zea mays

An indirect competitive enzyme-linked immunosorbent assay( ic-ELISA) was developed for the rapid detection of ochratoxin A( OTA) in nutmeg( Myristicae Semen),ginger( Zingiberis Rhizoma) and turmeric( Curcumae Longae Rhizoma). The matrix matching standard curve was used instead of the standard curve of sample diluent,and the sample extract and sample diluent were optimized. The sensitivity( IC_(50)) of this method for OTA in nutmeg,ginger and turmeric were determined as 0. 146,0. 157 and 0. 153 ng·m L~(-1),respectively and the limits of detection( LODs) were 0. 040,0. 032 and 0. 031 ng·m L~(-1),respectively. The recovery of samples ranged from 75. 99% to 122. 3%,with RSD<10%. Two positive samples for nutmeg and one positive sample for turmeric occurred in 50 samples,and the highest OTA contamination value was 1 167. 8 μg·kg~(-1). The results were further confirmed by LC-MS/MS. It shows that the developed ic-ELISA method is simple,rapid and sensitive,and can be applied for rapid and high-throughput screening of OTA in nutmeg,ginger and turmeric,as well as some other CHMs.
Chromatography, Liquid ; Drug Contamination ; Drugs, Chinese Herbal/analysis* ; Enzyme-Linked Immunosorbent Assay ; High-Throughput Screening Assays ; Ochratoxins/analysis* ; Tandem Mass Spectrometry

A one-step dual flow immunochromatographic assay (DICGA), based on a competitive format, was developed for simultaneous quantification of ochratoxin A (OTA) and zearalenone (ZEN) in corn, wheat, and feed samples. The limit of detection for OTA was 0.32 ng/ml with a detection range of 0.53‒12.16 ng/ml, while for ZEN it was 0.58 ng/ml with a detection range of 1.06‒39.72 ng/ml. The recovery rates in corn, wheat, and feed samples ranged from 77.3% to 106.3% with the coefficient of variation lower than 15%. Naturally contaminated corn, wheat, and feed samples were analyzed using both DICGA and liquid chromatography-tandem mass spectrometry (LC-MS/MS) and the correlation between the two methods was evaluated using a regression analysis. The DICGA method shows great potential for simple, rapid, sensitive, and cost-effective quantitative detection of OTA and ZEN in food safety control.
Animal Feed ; Calibration ; Chromatography, Affinity ; Chromatography, Liquid ; Colloids ; Food Contamination/analysis* ; Food Safety ; Gold ; Immunoassay/methods* ; Inhibitory Concentration 50 ; Limit of Detection ; Metal Nanoparticles ; Ochratoxins/analysis* ; Regression Analysis ; Reproducibility of Results ; Sensitivity and Specificity ; Triticum ; Zea mays ; Zearalenone/analysis*