Biotransformation of Methylene Blue by Mixed Fungal Cultures of Gloeophyllum trabeum and Aspergillus oryzae

This study investigated the biotransformation of methylene blue (MB) by mixed fungal cultures of Gloeophyllum trabeum and Aspergillus oryzae. Equal volumes of A. oryzae and G. trabeum cultures were applied to Erlenmeyer containing MB and incubated at 30°C for 7 days. The change in absorbance of the MB control solution and the solution after application, measured with a UV-Visible spectrophotometer, was used to calculate the decolorization. The addition of A. oryzae to G. trabeum cultures showed MB biodecolorization reaching 69.34%, greater than single cultures of G. trabeum and A. oryzae, which were 31.50% and 36.82%, respectively. Metabolite identification from MB biodecolorization by mixed culture using LC-QTOF-MS found the following metabolites: C16H20N3S, C19H22N3SO4, C31H48N3S+. The results of this study showed that the addition of A. oryzae enhanced the percentage of MB decolorization from G.