Formaldehyde as a Chemical Defence Agent of Fruiting Bodies of Mycena rosea and its Role in the Generation of the Alkaloid Mycenarubin†C.

Mycenarubin C, a previously unknown red pyrroloquinoline alkaloid, was isolated from fruiting bodies of the mushroom Mycena rosea and its structure was elucidated mainly by NMR spectroscopy and mass spectrometry. Unlike mycenarubin A, the major pyrroloquinoline alkaloid in fruiting bodies of M. rosea, mycenarubin C, contains an eight-membered ring with an additional C1 unit that is hitherto unprecedented for pyrroloquinoline alkaloids known in nature. Incubation of mycenarubin A with an excess of formaldehyde revealed that mycenarubin C was generated nearly quantitatively from mycenarubin A. An investigation into the formaldehyde content of fresh fruiting bodies of M. rosea showed the presence of considerable amounts of formaldehyde, with values of 5 µg per gram of fresh weight in fresh fruiting bodies. Although mycenarubin C did not show bioactivity against selected bacteria and fungi, formaldehyde inhibits the growth of the mycoparasite Spinellus fusiger at concentrations present in fruiting bodies of M. rosea. Therefore, formaldehyde might play an ecological role in the chemical defence of M. rosea against S. fusiger. In turn, S. fusiger produces gallic acid-presumably to detoxify formaldehyde by reaction of this aldehyde with amino acids and gallic acid to Mannich adducts.

Study on immunostimulating activity of macrophage treated with purified polysaccharides from liquid culture and fruiting body of Lentinus edodes.

Lentinus edodes is a well-known edible and medicinal mushroom used in Oriental cultures. Recently, L. edodes has attracted a lot of attention owing to its antifungal activity, antibacterial activity, antiviral activity, hepatoprotective effect, antitumor activities, and immunomodulatory and cytotoxic effects. In this study, the water-soluble crude polysaccharides, CPF and CPB, which were obtained from the fruiting body and culture cell-free broth of L. edodes by hot-water extraction and ethanol precipitation, were fractionated by DEAE cellulose and Sepharose CL-6B column chromatography, resulting in six polysaccharide fractions, CPFN-G-I, CPFN-G-II, CPFN-G-III, CPFA-G, CPBN-G, and CPBA-G. Among these fractions, CPFN-GI, CPBN-G, and CPBA-G were shown to stimulate the functional activation of macrophages including NO production cytokine expression and phagocytosis.

Occupational asthma caused by white mushroom.

The commercial growing of white mushroom (Agaricus bisporus) is a frequent activity in certain Spain regions as La Rioja. We report two cases of white mushroom workers suffering from asthma caused by hypersensitivity to basidiocarp and spores of white mushroom.