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A method for the quantitative determination of ganoderic acid A was constructed using the principle of indirect competitive enzyme-linked immunosorbent assay (ELISA), and this method was used to determine the ganoderic A contents of Ganoderma lucidum samples in the market. The conjugate of ganoderic acid A and bovine serum albumin was used for four rounds of immunization on test rabbits to obtain rabbit antiganoderic acid A antibody IgG. The enzyme-labeled plate was coated with the conjugate of ganoderic acid A and ovalbumin. The first stage reaction in the indirect competitive ELISA was that the conjugate of ganoderic acid A in the sample competed with the conjugate coated on the enzyme-labeled plate to bind rabbit antibodies. The second stage reaction was the combination of goat anti-rabbit IgG–horseradish peroxidase and rabbit antiganoderic acid A antibody IgG. The results of the determination of ganoderic acid A standard by this method showed that the coefficient of variation of repeated wells in the group was

Agaricus bisporus lectin (ABL), which is one of the antinutritional factors in A. bisporus, is an important allergen and harmful to human health. Due to the shortcomings of the current detection methods, it is extremely urgent to establish a rapid and sensitive detection method for ABL in foods. To isolate the ssDNA aptamer of ABL, 13 rounds of subtractive systematic evolution of ligands by exponential enrichment (SELEX) selection were carried out. As a result, six candidate aptamers were selected and further examined for their binding affinity and specificity by enzyme-linked aptamer method. One aptamer (seq-41) against ABL with a high affinity and specificity was isolated and demonstrated to be the optimal aptamer whose dissociation constant reaches the nanomolar level, Kd = 31.17 ± 0.1070 nM. Based on seq-41, an aptamer-AuNPs colorimetric method was established to detect ABL with a linear range of 0.08∼1.70 μg/mL and the detection limit is 0.062 μg/mL. This study provides a novel aptamer-AuNPs colorimetric method with high sensitivity and specificity for detection of ABL and a novel strategy for development of detection method of fungal or plant allergens.