Chloro- and Bromophenols from Cultures of Mycena alcalina

Abstract

Three new chlorinated phenols have been isolated from mycelial cultures of the mushroom Mycena alcalina. Their structures were determined by mass spectrometry and 1D and 2D NMR experiments. Addition of bromide to the medium resulted in the production of the corresponding brominated phenols. In addition, small amounts of the nonhalogenated precursor were also isolated, indicating that the halogenated metabolites are generated by a regioselectively operating halogenase.

Entonalactams A–C: Isoindolinone derivatives from an Australian rainforest fungus belonging to the genus Entonaema

“…Compounds 4-6 were identified as the previously reported natural products, 3-methoxy-5-methylbenzene-1,2-diol (4) (Peters and Spiteller, 2006;Pouchert, 1993), daldinal B (5) (Hashimoto et al, 1994) and ergosta-4,6,8(14),22-tetraen-3-one (6) (Hashimoto et al, 1994;Fujimoto et al, 2004;Schulte et al, 1968) …”

Chemical Defence Strategies of Higher Fungi

“…[48] In agreement with their bioactivity, investigations on the ecological role of the strobilurins demonstrated that S. tenacellus (German: Kiefernzapfenrübling), is able to prevent the growth of other fungi on the pine cone where the fungus grows. [5] Apart from the strobilurins, a number of other fungicides, such as pterulinic acid (19), [49] 4-O-acetyl hygrophorone A (20), [50] favolon (21) [51] or alcalinaphenol A (22), [52] have been isolated from mycelial cultures or fruiting bodies of higher fungi (Figure 3). Obviously, fungicides are wide- spread particularly in saprophytic fungi.…”

“…Accordingly, a GC-MS screening of trimethylsilylylated methanolic extracts from different Mycena species led to the identification of new chlorinated phenols, such as alcalinaphenol A (22), from mycelial cultures of Mycena alcalina. [52] Wound-Activated Chemical Defence…”

“…[75] Oxidation reactions in mushrooms are often initiated by rather unspecific tyrosinases or other enzymes with a similar function which are widespread in fungi and which only become active upon injury. [76] The oxidative degradation mechanism of aleurodisconitrile (51) to aleurodiscoester (52) and HCN differs fundamentally from that via oxidation of glycine in bacteria, [77] but also from the hydrolytic degradation of cyanogenic glycosides in plants. [78] While the ease of hydrolysis of the glycosidic bond by glycosidases is essential in plants, the high oxidisability of the aromatic residue is decisive in A. amorphus.…”

A Fivefold Parallelized Biosynthetic Process Secures Chlorination of Armillaria mellea (Honey Mushroom) Toxins

“…Therefore, further biochemical studies are necessary to shed more light on this fascinating enzyme family, in particular as members of basidiomycete origin have remained completely uninvestigated, even though aromatic haloorganic natural products are known from these fungi. Besides the melleolides, examples include the alcalinaphenols from Mycena alcalina (54) and stephanosporin of Stephanospora caroticolor (55). Hence, our work represents the first biochemically and genetically characterized basidiomycete halogenases.…”