Plant growth regulators from the fruiting bodies of Tricholoma flavovirens

Plant growth regulators from mushrooms

Plants interact with fungi in their natural growing environments, and relationships between plants and diverse fungal species impact plants in complex symbiotic, parasitic, and pathogenic ways. Over the past 10 years, we have intensively investigated plant growth regulators produced by mushrooms, and we succeeded in finding various regulators from mushroom-forming fungi: (1) fairy chemicals as a candidate family of new plant hormones from Lepista sordida, (2) agrocybynes A to E from fungus Agrocybe praecox that stimulate strawberry growth, (3) armillariols A to C and sesquiterpene aryl esters from genus Armillaria that are allelopathic and cause Arimillaria root disease, and (4) other plant growth regulators from other mushrooms, such as Stropharia rugosoannulata, Tricholoma flavovirens, Hericium erinaceus, Leccinum extremiorientale, Russula vinosa, Pholiota lubrica and Cortinarius caperatus.

Plant growth regulators and Axl and immune checkpoint inhibitors from the edible mushroom Leucopaxillus giganteus

A novel compound, (R)-4-ethoxy-2-hydroxy-4-oxobutanoic acid (1), and six known compounds (2-7) were isolated from the fruiting bodies of the wild edible mushroom Leucopaxillus giganteus. The planar structure of 1 was determined by the interpretation of spectroscopic data analysis. The absolute configuration of 1 was determined by comparing specific rotation of the synthetic compounds. In the plant regulatory assay, the isolated compounds (1-7) and the chemically prepared compounds (8-10) were evaluated their biological activity against the lettuce (Lactuca sativa) growth. Compounds 1 and 3-10 showed the significant regulatory activity of lettuce growth. 1 showed the strongest inhibition activity among the all the compounds tested. In the lung cancer assay, all the compounds were assessed the mRNA expression of Axl and immune checkpoints (PD-L1, PD-L2) in the human A549 alveolar epithelial cell line by RT-PCR. Compounds 1-10 showed significant inhibition activity against Axl and/or immune checkpoint.

Bitter compounds in two Tricholoma species, T. aestuans and T. virgatum

Lascivol was identified as the bitter compound in two Tricholoma species, T. aestuans and T. virgatum, and was previously isolated from the European mushroom T. lascivum. The structure of lascivol was previously solved by X-ray crystallographical analysis but its stereochemistry at C3 remained ambiguous. We thus re-examined the absolute configuration of C3 bearing a hydroxy group using the modified Mosher's method.

Biologically functional molecules from mushroom-forming fungi*

Fungi including mushrooms have been proved to be an important biosource of numerous metabolites having a huge variety of chemical structures and diverse bioactivities. Metabolites of mushrooms are of remarkable importance as new lead compounds for medicine and agrochemicals. This review presents some of our studies on biologically functional molecules purified from mushroom-forming fungi; (1) endoplasmic reticulum stress suppressor, (2) osteoclast-forming suppressing compounds, (3) plant growth regulators.

Biomimetic synthesis of the bisindole framework present in sciodole, an alkaloid fromTricholoma sciodes

The unique bisindole bond present in the alkaloid sciodole can be forged by amination of an azafulvene, validating a biosynthetic hypothesis.