Publications by authors named "Zhengyou Yang"

Lycium barbarum is widely distributed in China and used as a traditional Chinese medicine herb to treat dizziness, abdominal pain, dry cough, headache and fatigue. Several studies have examined the endophytes of L. barbarum from northwest China; however, few have focused on that from eastern China.

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Small molecule-induced fermentation of the endophytic fungus sp. AC1 originated from was executed to investigate its secondary metabolites. It was fermented in a culture medium containing 5-hydroxytryptophan (5-HTP), 1-methyl-L-tryptophan (1-MT), and tryptamine (TA), respectively.

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Article Synopsis
  • Researchers developed a green electrochemical immunosensor that efficiently detects O,O-dimethyl organophosphorus pesticides (OPs) using phage-mimotope M31 and horseradish peroxidase (HRP).
  • The sensor was built on a glassy carbon electrode enhanced with nitrogen and boron doped carbon quantum dots and graphene oxide to improve conductivity and surface area.
  • The immunosensor demonstrated excellent sensitivity, with a 50% inhibitory concentration range of 0.989-4.017 ng/mL and recovery rates of spiked OPs in food samples between 88.20-112.50%.
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Endophytic fungi of medicinal plants are important sources of active natural products. In this study, 26 fungi were isolated from , which were belonging to eight genera, namely, , , , , , , , and . The antimicrobial activities of all fungal extracts were tested by using the cup-plate method against , , and .

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Noncompetitive immunoassays for small molecules are generally considered to be more sensitive than competitive ones. In this study, a phage-peptide against immune complex of aflatoxin B1 (AFB1) and nanobody Nb28 was obtained by phage-display technology. The phage-peptide was labeled with peroxidase and used to develop a direct noncompetitive magnetic-chemiluminescent enzyme-linked immunoassay (Nc-MCLEIA) for AFB1.

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Article Synopsis
  • Organophosphorus pesticides (OPs) are common in agriculture, and monitoring their residues is crucial for human health, making effective detection methods necessary.
  • A new noncompetitive magnetic-phage anti-immunocomplex assay (MPHAIA) was developed, utilizing peptides identified from a phage display library to improve sensitivity and specificity for detecting OPs.
  • Validation of MPHAIA showed promising results, with limits of detection for various OPs and reliable accuracy confirmed through testing on spiked cucumber samples, compared to gas chromatography-tandem mass spectrometry (GC-MS/MS).
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Toxic small molecule contaminants (SMCs) residues in food threaten human health. Immunoassays are popular and simple techniques for SMCs analysis. However, immunoassays based on polyclonal antibodies, monoclonal antibodies and chemosynthetic antigens have some defects, such as complicated preparation of antibodies, risk of toxic haptens using for antigen chemosynthesis and so on.

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Oxidative stress-induced series of related degenerative diseases have received widespread attention. To screen new lactic acid bacteria (LAB) strains to resist oxidative stress, traditional Chinese fermented vegetables were used as a resource library to screen of LAB. The JX306 strain, which showed high scavenging activity of DPPH free radical and hydrogen radical, and a strong lipid peroxidation inhibition rate was selected.

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Here we demonstrate a novel phage-magnetic-chemiluminescent enzyme immunoassay (P-MCLEIA) for detection of zearalenone (ZEN). The P-MCLEIA was more efficient than conventional ELISA through several improvements. In the P-MCLEIA, magnetic nanoparticles were replaced of microplates as solid phases to reduce the whole incubation time within 40 min.

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The purpose of the present study was to discover antimicrobial endophytic fungi from Three fungal endophytes with antibacterial activity were isolated and determined as sp. HQ-1, sp. HQ-7 and sp.

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Article Synopsis
  • Mimotopes, which can replace harmful mycotoxins, are being used to develop new immunoassay methods with a focus on aflatoxin B1 (AFB).
  • Researchers created a magnetic beads-based competitive ELISA (MB-dcELISA) that effectively utilizes a specific nanobody (Nb28) and its mimotope (ME17) for detection.
  • The new immunoassay demonstrated strong performance with low detection limits and good recovery rates in various food samples, offering a promising strategy for monitoring AFB and similar toxic compounds.
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To investigate the role of Tobacco vein banding mosaic virus (TVBMV) 3'-UTR in virus systemic infection, three types of deletions were introduced into TVBMV infectious clone pCaTVBMV-GFP. Mutants with deletions at the nucleotide position 8-42, 43-141, or 163-174 in the 3'-UTR failed to cause systemic infection in N. benthamiana plants.

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High cholesterol level in serum is a major factor of influence for coronary heart disease. The cholesterol-lowering ability of lactic acid bacteria (LAB) without side effects makes them more and more attractive. Seventy-nine strains of LAB isolated from fermented food were screened in vitro for their ability to assimilate cholesterol.

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The multi-residue determination of organophosphorus pesticides (OPs) is an important task due to the wide application and high toxicity of OPs. However, there is no promising immunoassay to monitor the multi-residue of O,O-dimethyl OPs. In this study, a monoclonal antibody (mAb) against a generic hapten of O,O-dimethyl OPs (O,O-dimethyl O-(3-carboxyphenyl)phosphorothioate) was prepared.

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Organophosphorus pesticides (OPs) are the most widely used pesticides in agriculture, and OP residues have been broadly reported in food and environmental samples. The aim of this study is to develop a recombinant antibody-based broad-specificity immunoassay for OPs. A phage display library was prepared from a mouse pre-immunized with a generic immunogen of OPs, and a single-chain variable fragment (scFv) antibody was selected.

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The economic losses caused by postharvest fruits diseases have attracted global attention. Traditional chemical fungicide could not meet the need of humans. In recent years, microbial agent which has begun to take the place of chemical fungicide comes into people's vision.

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In this article, we reported the development of a biotinylated single-chain variable fragment (scFv) antibody based indirect competitive enzyme-linked immunosorbent assay (IC-ELISA) for parathion-methyl (PM) detection. Firstly, a phage display library was generated using a pre-immunized BALB/C mouse against a specific hapten of PM. After four rounds of panning, the scFv gene fragments were transferred into a secreted expression vector.

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The economic losses caused by postharvest fruits diseases have attracted global attention. Traditional chemical fungicide could not meet the need of humans. In recent years, microbial agent which has begun to take the place of chemical fungicide comes into people’s vision.

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To develop a broad-specificity immunoassay for organophosphorus pesticides (OPs), a broad-specificity monoclonal antibody (MAb) for OPs against a generic hapten, O,O-diethyl O-(3-carboxyphenyl) phosphorothioate with the carboxy group in the meta position of the benzene ring, was produced. Eight haptens were prepared and covalently attached to ovalbumin (OVA) for use as coating antigens, and the optimum coating antigen was selected. Then, a sensitive and broadly class selective competitive indirect enzyme-linked immunosorbent assay (ciELISA) based on the MAb and the optimum coating antigen (hapten H-OVA, possessing an O,O-dimethyl generic structure and linked through a linear spacer arm) was developed and optimized.

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Multiple plant viruses, including potato virus X (PVX), have been modified as vectors for expressing heterologous genes or silencing endogenous genes in plants. PVX-based vectors facilitate the functional analysis of genes in plant. However, they can only express one protein in a time.

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Rapid detection of enterotoxigenic Clostridium perfringens in meat samples was accomplished with an immunomagnetic separation polymerase chain reaction (IMS-PCR). First, a monoclonal antibody (mAb) specific to C. perfringens was generated.

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Article Synopsis
  • Three detection methods for Listeria monocytogenes in meat samples were developed, including ELISA, ICG strip tests, and IMBS systems, all showing strong reactions with Listeria and weak reactions with Staphylococcus aureus.
  • * Combining ELISA and ICG with IMBS reduced the required enrichment time from 24 hours to 14 hours, allowing for faster detection of L. monocytogenes in contaminated meat.
  • * The new methods (ELISA-IMBS and ICG-IMBS) demonstrate similar accuracy to standard methods and can detect L. monocytogenes within 15 hours, making them promising for rapid and cost-effective screening in food safety.
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Article Synopsis
  • Researchers developed a rapid immunochromatography (ICG) strip test to detect aflatoxin B1 (AFB1) using a nanocolloidal gold-antibody probe, achieving a visual detection limit of 0.5 ng/ml.
  • The test was designed with a specific monoclonal antibody that reacts not only to AFB1 but also to related aflatoxins B2, G1, and G2.
  • Results from the ICG test were consistent with traditional HPLC analysis across 172 grain and feed samples, showing its potential as a fast, cost-effective screening method for mycotoxins in food and agricultural products, with results deliverable in just 15 minutes.
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An immunochromatography (ICG) strip test based on a monoclonal antibody for the rapid detection of L. monocytogenes in meat and processed-meat samples was developed in this study. A monoclonal antibody (MAb) specific to L.

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A monoclonal antibody (mab) against the antimicrobial sulfamethazine was prepared and characterized by an indirect competitive enzyme-linked immunosorbent assay (IC-ELISA). Sulfamethazine in the range of 0.2 and 45 ng/ml could be determined with the mab by IC-ELISA.

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