The Microbiome Dynamics During The Self-Heated Two-Phase Composting Process For Agaricus Bisporus Mushroom And The Characteristic Function Study Of Typical Microbe

Agaricus bisporus mushroom, which is called white button mushroom, is one of the most commonly and widely consumed mushrooms in the world. Because growth substrates for Agaricus mushrooms are basically agricultural and industrial discards that are inedible for humans, cultivated mushrooms play a crucial role in the endeavor to increase food protein, and improve the agricultural economic and environment situation.The self-heated two-phase composting was operated in mushroom factory to simulate the growth model of wild Agaricus mushrooms in the nature environment. This kind of composting is a low-carbon and effective method to produce cultivation substrates for Agaricus mushrooms. In this research, we studied the growth and metabolism of microbes during the self-heated two-phases composting process, to investigate how the microbes prepared an appropriate environment for the growth of Agaricus mushrooms. Meanwhile, the antifungal activity of antagonistic bacteria during the mycelial growth stage of Agaricus mushrooms, and the anti-tumor activity of endophyte bacteria from fruit bodies of Agaricus mushrooms were studied. The major findings are as follows:The effects of forced aeration schemes during the first stage of self-heated two-phases composting on the solid fermentation process were studied. Results showed that the yields as well as qualities of mushrooms, and the biological efficiencies of mushroom cultivation substrates were not significantly influenced when the aeration time decreased from10to8min. However, the energy consumption was cut down by20%. Forced aeration could regulate the immobilization of organic nitrogen, and the consumption of carbohydrate components by microbes in substrates. Consequently, influenced the quality of the cultivation substrates for Agaricus mushrooms.Bacillus subtilis strain B154isolated from A. bisporus mushroom compost exhibited predominantly antagonistic activities against the red bread mold Neurospora sitophila. An antifungal substance was separated and purified by20%ammonium sulfate precipitation and DEAE-Sephadex A50anion exchange chromatography from B154. It could effectively inhibit the mycelia growth and spores germination of N. sitophila. Treatment with B154inoculum significantly increased the yield of Agaricus mushrooms infected by N. sitophila. UV scan spectroscopy, Tricine-SDS-PAGE, MALDI-TOF MS and ESI-MS/MS analysis showed that the antifungal peptide was a fengycin A compound with molecular weight at1477Da.B. subtilis AB154with anti-proliferation activity on human cancer cells was isolated from the fruit bodies of Agaricus mushrooms. The anti-tumor peptides isolated from endophyte AB154could strongly inhibited the proliferation of human colon cancer cell line Caco-2, while the inhibitory ability on human normal bronchial epithelial cell line NHBE was the lowest. HPLC separation, MALDI-TOF MS, and ESI-MS/MS analysis showed that the two peptides produced by B. subtilis AB154belonged to the lipopeptide family of fengycin Bl and surfacrtin. The study of inhibitory mechanisms showed that the cell cycle arresting effects of two compounds on Caco-2cells were different. The fragmentation of nuclear chromatin within Caco-2cells was induced by bith fengycin and surfacti. According to Real-time PCR and immunofluorescence tests, these two kinds of lipo-peptides could arrest the cell cycle through the inhibition of PI3K-Akt pathway.