Effect of different culture media on secondary metabolite production of Xylaria sp. SWUF08-81

Fungi are known to produce a diverse range of bioactive metabolites. This diversity occurs because of a combination of species complexity and growth environments. A number of research projects have investigated the effects of fungi growth conditions on the compounds they produced including pH, temperature, and type of culture media [1],[2],[3]. This allowed the researchers to establish the various compounds profiles and their potential use as drug candidates. There are numerous reports on bioactive compounds from Xylaria spp. but only a few have concentrated on the possible impacts of culture media on the compounds [4].

The aim of this research is to study the effect of different culture media, namely GM and PDB, on the metabolites produced and their biological activity, from the wood-decaying fungus Xylaria sp. SWUF08-81. There were sixteen compounds isolated from GM medium, five of which were cytochalasin derivatives (1-5) together with three mellein, six simple monocyclic and three potential new compounds such as dibenzofuran, mellein and pyrone derivatives. From the PDB medium, nine compounds were identified including two new and five known dihydroisocoumarins derivatives (6-10) and two auroglucins. The structure elucidation of the other compounds is ongoing. The preliminary bioassay screening at 100 µg/mL showed that 6, 7 and the new dibenzofuran were toxic against HCT116, HT29, MCF-7, Hela and Vero cells at a percentage of cell viability < 30 %.

It can be concluded that the Xylaria sp. SWUF08-81 fungus produced entirely different classes of compounds when the growth culture media were altered.

Fig. 1 Some isolated compounds from Xylaria sp. SWUF08-81 fungus.

• References

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