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Ganoderma lucidum is a very precious traditional Chinese medicine. It has good pharmacological effects because of its polysaccharides, triterpenoids and other biological activities. Ganoderma lucidum mycelium is rich in Ganoderma lucidum polysaccharides and other substances, but it is difficult to obtain under natural conditions, so it is generally obtained through artificial inoculation or fermentation. Therefore, it is imperative to optimize the mycelium fermentation conditions. The range of fermentation time, temperature and pH of response surface analysis was determined by single factor experiment. The optimal fermentation conditions were fermentation temperature 28℃, pH=7, fermentation time 7 days, and mycelium biomass of (7±0.1) g/L. The results provide data reference for better utilization and development of Ganoderma lucidum.

An ultrahigh-performance liquid chromatography–tandem mass spectrometry method was developed and validated for the simultaneous determination of sterigmatocystin, verruculogen, enniatin A, fusarenon-X, fumonisins B1, B2, B3, aflatoxins B1, B2, G1, G2, ochratoxin A, deoxynivalenol, 3-acetyldeoxynivalenol, 5-acetyldeoxynivalenol, and zearalenone. The mycotoxins were extracted and cleaned up using a multitoxin column, separated on a C18 column, and then detected on a triple-quadrupole mass spectrometer. The limits of detection and quantification ranged within 0.2–2 µg/kg and 1–10 µg/kg, respectively. The recoveries ranged from 70.8 to 118.4%, with relative standard deviations below 15%. The method was used to analyze 80 samples obtained from Shandong Province in China. Fifty-eight samples were contaminated with 10 mycotoxins at concentrations ranging from 1.4 to 6566.1 µg/kg. Some samples exceeded the maximum limits in China and in European regulations for mycotoxins in unprocessed maize. [ABSTRACT FROM PUBLISHER]

Aflatoxin B1 (AFB1) is a common toxin found in many foods. While AFB1 sensors have been reported, few studies have shown amplified detection with tunable dynamic ranges. We herein report a simple and highly sensitive amplified aptamer-based fluorescent sensor for AFB1, which relies on the ability of nano-graphene oxide (GO) to protect aptamers from nuclease cleavage for amplified detection and on the nanometer size effect of GO to tune the dynamic range and sensitivity. The assay was performed by simply mixing the carboxyl-X-rhodamine (ROX)-labeled AFB1 aptamer, the GO, the nuclease, and the AFB1 samples. Modulating the size of the GO nanosheet resulted in three dynamic ranges, i.e., 12.5 to 312.5 ng mL−1, 1.0 to 100 ng mL−1, and 5.0 to 50 ng mL−1, with corresponding limits of detection of 10.0 ng mL−1, 0.35 ng mL−1 and 15.0 ng mL−1, respectively. The sensor was highly selective against other aflatoxins and common molecules in foods, and its performance was verified in corn samples spiked with known concentration of AFB1. [ABSTRACT FROM AUTHOR]