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Aflatoxin is a strong carcinogenic and toxic fungal toxin produced by Aspergillus flavus and other Aspergillus species, and can seriously threaten the health of consumers, thus becoming a global concern. Aflatoxin in agricultural products are closely related to biogeography and symbiotic microorganisms. It is not fully clear that how biogeography affects the assembly process of A. flavus and symbiotic microorganisms on plant. In this study, we analyzed the structure and assembly process of fungi and bacteria on the peanut. We also performed metagenome analysis to assess the relationships between functional genes and metabolic pathways in the microorganisms, aflatoxin and biogeography. Finally, our data showed that inoculation of beneficial microorganisms isolated from the healthy peanut-associated microbiome could significantly inhibit the enrichment of A. flavus and the production of aflatoxin in inoculated plants. Our results indicate that biogeography can significantly influence the assembly process of microorganisms, the activation of functional genes and metabolic pathways, the enrichment of aflatoxin-producing fungi. Manipulation of the peanut-associated microbiome, for instance, by inoculating peanut with beneficial strains, has potential to promote plant health. This will provide us with new ideas and perspectives on the early warning and effective prevention and control of aflatoxin contamination in agricultural products.
Yanpo Yao; Suyan Gao; Xiaoxia Ding; Peiwu Li; Qi Zhang. The microbial population structure and function of peanut peanut and their effects on aflatoxin contamination. LWT 2021, 148, 111285 .
AMA StyleYanpo Yao, Suyan Gao, Xiaoxia Ding, Peiwu Li, Qi Zhang. The microbial population structure and function of peanut peanut and their effects on aflatoxin contamination. LWT. 2021; 148 ():111285.
Chicago/Turabian StyleYanpo Yao; Suyan Gao; Xiaoxia Ding; Peiwu Li; Qi Zhang. 2021. "The microbial population structure and function of peanut peanut and their effects on aflatoxin contamination." LWT 148, no. : 111285.
Anti-idiotypic nanobodies, usually expressed by gene engineering protocol, has been shown as a nontoxic coating antigen for toxic compound immunoassays. We here focused on how to increase immunoassay sensitivity by changing the nanobody’s primary sequence. In the experiments, two anti-idiotype nanobodies against monoclonal antibody 1H2, which is specific to ochratoxin A, were obtained and named as nontoxic coating antigen 1 (NCA1) and nontoxic coating antigen 2 (NCA2). Three differences between the nanobodies were discovered. First, there are six amino acid residues (AAR) of changes in the complementarity determining region (CDR), which compose the antigen-binding site. One of them locates in CDR1 (I–L), two of them in CDR2 (G–D, E–K), and three of them in CDR3 (Y–H, Y–W). Second, the affinity constant of NCA1 was tested as 1.20 × 108 L mol−1, which is about 4 times lower than that of NCA2 (5.36 × 108 L mol−1). Third, the sensitivity (50% inhibition concentration) of NCA1 for OTA was shown as 0.052 ng mL−1, which was 3.5 times lower than that of nontoxic coating antigen 2 (0.015 ng mL−1). The results indicate that the AAR changes in CDR of the anti-idiotypic nanobodies, from nonpolar to polar, increasing the affinity constant may enhance the immunoassay sensitivity. In addition, by using the nontoxic coating antigen 2 to substitute the routine synthetic toxic antigen, we established an eco-friendly and green enzyme-linked immunosorbent assay (ELISA) method for rapid detection of ochratoxin A in cereals. The half-maximal inhibitory concentration (IC50) of optimized ELISA was 0.017 ng mL−1 with a limit of detection (LOD) of 0.003 ng mL−1. The optimized immunoassay showed that the average recoveries of spiked corn, rice, and wheat were between 80% and 114.8%, with the relative standard deviation (RSD) ranging from 3.1–12.3%. Therefore, we provided not only basic knowledge on how to improve the structure of anti-idiotype nanobody for increasing assay sensitivity, but also an available eco-friendly ELISA for ochratoxin A in cereals.
Caixia Zhang; Weiqi Zhang; Xiaoqian Tang; Qi Zhang; Wen Zhang; Peiwu Li. Change of Amino Acid Residues in Idiotypic Nanobodies Enhanced the Sensitivity of Competitive Enzyme Immunoassay for Mycotoxin Ochratoxin A in Cereals. Toxins 2020, 12, 273 .
AMA StyleCaixia Zhang, Weiqi Zhang, Xiaoqian Tang, Qi Zhang, Wen Zhang, Peiwu Li. Change of Amino Acid Residues in Idiotypic Nanobodies Enhanced the Sensitivity of Competitive Enzyme Immunoassay for Mycotoxin Ochratoxin A in Cereals. Toxins. 2020; 12 (4):273.
Chicago/Turabian StyleCaixia Zhang; Weiqi Zhang; Xiaoqian Tang; Qi Zhang; Wen Zhang; Peiwu Li. 2020. "Change of Amino Acid Residues in Idiotypic Nanobodies Enhanced the Sensitivity of Competitive Enzyme Immunoassay for Mycotoxin Ochratoxin A in Cereals." Toxins 12, no. 4: 273.
T-2 and HT-2 toxins and their main modified forms (T-2 glucoside and HT-2 glucoside) may co-occur in cereals and cereal-based products. A fluorescence polarization immunoassay (FPIA) was developed for the simultaneous determination of T-2 toxin, HT-2 toxin and relevant glucosides, expressed as sum. The developed FPIA, using a HT-2-specific antibody, showed high sensitivity (IC50 = 2.0 ng/mL) and high cross-reactivity (100% for T-2 toxin and 80% for T-2 and HT-2 glucosides). The FPIA has been used to develop two rapid and easy-to-use methods using two different extraction protocols, based on the use of organic (methanol/water, 90:10, v/v) and non-organic (water) solvents, for the determination of these toxins in wheat. The two proposed methods showed analytical performances in terms of sensitivity (LOD 10 µg/kg) recovery (92-97%) and precision (relative standard deviations ≤13%), fulfilling the criteria for acceptability of an analytical method for the quantitative determination of T-2 and HT-2 toxins established by the European Union. Furthermore, the methods were then validated in accordance with the harmonized guidelines for the validation of screening methods included in the Regulation (EU) No. 519/2014. The satisfactory analytical performances, in terms of intermediate precision (≤25%), cut-off level (80 and 96 µg/kg for the two methods) and rate of false positives (<0.1%) confirmed the applicability of the proposed methods as screening method for assessing the content of these toxins in wheat at the EU indicative levels reported for T-2 and HT-2 toxins.
Vincenzo Lippolis; Anna C. R. Porricelli; Erminia Mancini; Biancamaria Ciasca; Veronica M. T. Lattanzio; Annalisa De Girolamo; Chris M. Maragos; Susan McCormick; Peiwu Li; Antonio F. Logrieco; Michelangelo Pascale. Fluorescence Polarization Immunoassay for the Determination of T-2 and HT-2 Toxins and Their Glucosides in Wheat. Toxins 2019, 11, 380 .
AMA StyleVincenzo Lippolis, Anna C. R. Porricelli, Erminia Mancini, Biancamaria Ciasca, Veronica M. T. Lattanzio, Annalisa De Girolamo, Chris M. Maragos, Susan McCormick, Peiwu Li, Antonio F. Logrieco, Michelangelo Pascale. Fluorescence Polarization Immunoassay for the Determination of T-2 and HT-2 Toxins and Their Glucosides in Wheat. Toxins. 2019; 11 (7):380.
Chicago/Turabian StyleVincenzo Lippolis; Anna C. R. Porricelli; Erminia Mancini; Biancamaria Ciasca; Veronica M. T. Lattanzio; Annalisa De Girolamo; Chris M. Maragos; Susan McCormick; Peiwu Li; Antonio F. Logrieco; Michelangelo Pascale. 2019. "Fluorescence Polarization Immunoassay for the Determination of T-2 and HT-2 Toxins and Their Glucosides in Wheat." Toxins 11, no. 7: 380.
Mycotoxins and pesticides are prevalent in cereal food. It is difficult to detect these two kinds of hazard factors simultaneously in rapid assay. In order to find a solution to the problem, carbamates and aflatoxins were selected in this study to establish a rapid, on-site, and quantitative paper sensor. Two novel monoclonal antibodies (mAbs) against carbaryl and carbofuran (1D2 and G11) were developed. The IC50 values (half maximal inhibitory concentration) were 0.8 ng/mL and 217.6 ng/mL for carbaryl and carbofuran, respectively. Based on the sensitive and specific mAbs, a multi-TRFICA (time-resolved fluorescence) paper sensor was developed, which simultaneously detected six types of hazardous chemicals, including AFB1, AFB2, AFG1, AFG2, carbaryl, and carbofuran. A universal sample pretreatment method for mycotoxins and pesticides was explored to apply on established competitive indirect enzyme-linked immunosorbent assay (icELISA) and multi-TRFICA-paper sensor. The established paper sensor can be easily observed with naked eyes, qualitatively under a UV lamp, and quantitated using a home-made device. It exhibited a calculated limit of quantity for AFTs, carbaryl, and carbofuran of 0.03, 0.02, and 60.2 ng/mL in corn samples, respectively. The spiking-recoveries and real sample studies proved that multi-TRFICA-paper sensor is an accurate, sensitive, and high throughput detection method for simple and low-cost analysis in corn samples.
Xiaoqian Tang; Qi Zhang; Zhaowei Zhang; Xiaoxia Ding; Jun Jiang; Wen Zhang; Peiwu Li. Rapid, on-site and quantitative paper-based immunoassay platform for concurrent determination of pesticide residues and mycotoxins. Analytica Chimica Acta 2019, 1078, 142 -150.
AMA StyleXiaoqian Tang, Qi Zhang, Zhaowei Zhang, Xiaoxia Ding, Jun Jiang, Wen Zhang, Peiwu Li. Rapid, on-site and quantitative paper-based immunoassay platform for concurrent determination of pesticide residues and mycotoxins. Analytica Chimica Acta. 2019; 1078 ():142-150.
Chicago/Turabian StyleXiaoqian Tang; Qi Zhang; Zhaowei Zhang; Xiaoxia Ding; Jun Jiang; Wen Zhang; Peiwu Li. 2019. "Rapid, on-site and quantitative paper-based immunoassay platform for concurrent determination of pesticide residues and mycotoxins." Analytica Chimica Acta 1078, no. : 142-150.
High complexity of identification for non-target triacylglycerols (TAGs) is a major challenge in lipidomics analysis. To identify non-target TAGs, a powerful tool named accurate MSn spectrometry generating so-called ion trees is used. In this paper, we presented a technique for efficient structural elucidation of TAGs on MSn spectral trees produced by LTQ Orbitrap MSn, which was implemented as an open source software package, or TIT. The TIT software was used to support automatic annotation of non-target TAGs on MSn ion trees from a self-built fragment ion database. This database includes 19108 simulate TAG molecules from a random combination of fatty acids and corresponding 500582 self-built multistage fragment ions (MS ≤ 3). Our software can identify TAGs using a “stage-by-stage elimination” strategy. By utilizing the MS1 accurate mass and referenced RKMD, the TIT software can discriminate unique elemental composition candidates. The regiospecific isomers of fatty acyl chains will be distinguished using MS2 and MS3 fragment spectra. We applied the algorithm to the selection of 45 TAG standards and demonstrated that the molecular ions could be 100% correctly assigned. Therefore, the TIT software could be applied to TAG identification in complex biological samples such as mouse plasma extracts.
Xiupin Wang; Qingzhi Peng; Peiwu Li; Qi Zhang; Xiaoxia Ding; Wen Zhang; Liangxiao Zhang. Identification of triacylglycerol using automated annotation of high resolution multistage mass spectral trees. Analytica Chimica Acta 2016, 940, 84 -91.
AMA StyleXiupin Wang, Qingzhi Peng, Peiwu Li, Qi Zhang, Xiaoxia Ding, Wen Zhang, Liangxiao Zhang. Identification of triacylglycerol using automated annotation of high resolution multistage mass spectral trees. Analytica Chimica Acta. 2016; 940 ():84-91.
Chicago/Turabian StyleXiupin Wang; Qingzhi Peng; Peiwu Li; Qi Zhang; Xiaoxia Ding; Wen Zhang; Liangxiao Zhang. 2016. "Identification of triacylglycerol using automated annotation of high resolution multistage mass spectral trees." Analytica Chimica Acta 940, no. : 84-91.