Melanin synthesis by black yeast-like fungi Psedonadsoniella brunnea: dependence of L-tyrosine quantity in the cultural medium

Abstract

To determine the optimal conditions for the synthesis of melanin by black yeast fungi Pseudonadsoniella brunnea (Basidiomycota, Agaricomycotina, Agaricomycetes, Polyporales, Meripilaceae), depending on the amount of L-tyrosine in the culture medium was the purpose of the work. The standard Malt Extract Broth (MEB) liquid nutrient medium was used within this study. L-tyrosine was added to the culture medium in a quantity of 0.01, 0.025 and 0.05%.To obtain the melanin the cultivation of Pseudonadsoniella brunnea was carried out at pH 1-1.5, temperature + 21 ± 1 ° C during 7 days. Statistical processing of the results was carried out using generally accepted methods of variation statistics. It has been established that the level of melanin synthesis by black yeast-like fungi Pseudonadsoniella brunnea depends on the amount of L-tyrosine introduced into the culture medium. The MEB nutrient medium containing 0.05% L-tyrosine in this series of experiments found to be the best composition for obtaining melanin by the strain-producer Pseudonadsoniella brunnea. Compared to control (MEB without L-tyrosine), the amount of melanin synthesized by Ps. brunnea in these conditions increased by 2.5 times. The further research into the optimal conditions for the cultivation of black yeast-like fungi Pseudonadsoniella brunnea in order to obtain melanin is relevant and promising.