Using Illumina sequencing and MNP marker screening, 31 strains of Pleurotus eryngii and the main cultivated variety ‘Ple 0100’ in Fujian Province were used to construct a database containing 503 MNP markers for genetic similarity （GS） analysis and variety identification. The results showed that the GS of the 32 strains ranged between 1.79% and 99.60%, among which the GS of DUS16 and DUS17 was 99.60%, that between DUS02 and DUS23 or DUS30 was 99.01%, and that between DUS23 and DUS30 was 99.20%. There was no antagonistic reaction between strains with a high GS, and they may be very similar or the same. MNP markers were used to analyze fruiting bodies, fruiting body tissue isolates, cultivation residue, fruiting body base samples from three P.eryngii production factories, and the results showed that these samples were 100% similar to ‘Ple 0100’, suggesting that MNP markers can be used for variety identification of samples other than mycelium. Five inbred strains and their parents were detected by MNP markers. The results showed that the GS between the inbred strains ranged between 26.84% and 61.43%, and that between the inbred strains and their parents ranged between 28.43% and 78.33%, suggesting that there were extensive chromosome recombination and homologous chromosome exchange during the meiosis of P. eryngii. Tissue isolates of 56 commercial mushrooms from 52 P. eryngii factories in China were detected by MNP markers, and their similarity with ‘Ple 0100’ was 100.00%, indicating that the cultivated varieties of P. eryngii in China were highly consistent. The MNP molecular marker technique in combination with next-generation sequencing can be used to analyze the genetic similarity between P. eryngii strains and identify new strains.

Using qRT-PCR, the 10 laccase genes in the genome of Pleurotus eryngii were determined for relative expression level at different developmental stages (mycelium, knot, primordium, young mushroom and fruiting body). Laccase activity and relative lignin content in the culture substrate of P. eryngii at the five different developmental stages were also measured. The results showed that lignin content in the culture substrate initially decreased and then increased. The lowest lignin content was found in the knot stage at 6.49%, and the lignin contents at the young mushroom and fruiting body stages were 7.43% and 7.52%, respectively. Laccase activity was relatively high during the fruiting body stage at 3.72×10⁴ U·mL^-1 and there was no significant difference in laccase acitivity among the rest four stages. At both the mycelium and fruting body stages, the expression of Lac5 and Lac6 were higher than other laccase genes. For the knot, primordium and young mushromm stages, laccase genes with the highest expression level were Lac10, Lac9 and Lac3, respectively.

Using single factor experiments, the effects of extraction time, temperature, solid-liquid ratio and volumetric ethanol concentration on extraction rate and fruiting body polysaccharide content of Clitocybe squamulosa were studied and the results were then used to optimize the extraction process by response surface design. The obtained C. squamulosa fruiting body polysaccharide extract was subjected to structural characterization and functional property study using scanning electron microscopy, Fourier transform infrared spectroscopy, ion chromatography, multi-angle laser light scattering gel permeation chromatography (GPC) and rheometer. The results showed that the optimal extraction conditions were as follows: extraction time 3.6 h, 80 ℃, solid-liquid ratio of 1∶30 (g∶mL), and volumetric ethanol concentration of 80%. The extraction rate under the optimal conditions was (4.07±0.05)%, which was close to the predicted value of the response surface. The obtained polysaccharide extract was found to be mainly composed of irregular spherical structures with a pyranose ring skeleton; and it has no nucleic acid or protein residue. The relative molecular weight of the polysaccharide extract was found to be 1.948×10⁴, comprising glucose, mannose, galactose and rhamnose at a molar ratio of 1.07∶0.38∶0.11∶0.02. Under different concentrations, temperature and pH, the apparent viscosity of the polysaccharide extract solution decreased with increasing shear rate, suggesting a typical pseudoplastic non Newtonian fluid characteristics. In addition, the polysaccharide extract showed good oil retention property (5.92±0.20) g·g^-1 and emulsibility (94. 92±1.19)%.