Antibacterial metabolites from Australian macrofungi from the genus Cortinarius
Beattie, KD and Rouf, R and Gander, L and May, TW and Ratkowsky, DA and Donner, CD and Gill, M and Grice, IG and Tiralongoa, E, Antibacterial metabolites from Australian macrofungi from the genus Cortinarius, Phytochemistry: International Journal of Plant Biochemistry, 71, (8-9) pp. 948-955. ISSN 0031-9422 (2010) [Refereed Article]
In this study, ethyl acetate and aqueous fractions from 117 collections of Australian macrofungi belonging to the mushroom genus Cortinarius were screened for antimicrobial activity against Staphylococcus aureus and Pseudomonas aeruginosa. Overall, the lipophilic fractions were more active than the aqueous fractions. The ethyl acetate fractions of most or all collections of 13 species, namely Cortinarius ardesiacus, C. archeri, C. austrosaginus, C. austrovenetus, C. austroviolaceus, C. coelopus, C. [Dermocybe canaria]2, C. clelandii, C. [D. kula], C. memoria-annae, C. persplendidus, C. sinapicolor, C. vinosipes and forty seven collections of un-described Cortinarius species exhibited IC50 values of less-than-or-equals, slant0.09 mg/mL against S. aureus. In contrast, most or all collections of only four species, namely C. abnormis, C. austroalbidus, C. [D. kula], C. persplendidus, and eleven un-described Cortinarius collections exhibited similar effects against P. aeruginosa (IC50 less-than-or-equals, slant 0.09 mg/mL). Anthraquinonoid pigments isolated from C. basirubescens together with emodin physcion and erythrogluacin were assessed for their antimicrobial activity. The fungal octaketides austrocortilutein, austrocortirubin, torosachrysone, physcion and emodin were found to strongly inhibit the growth of S. aureus (IC50 0.7–12 μg/mL) whereas only physcion and emodin exhibited potency against P. aeruginosa (IC50 1.5 and 2.0 μg/mL, respectively).