The effect of citrate and sulfate of different metals on carbohydrates composition of medicinal mushroom Trametes versicolor (Polyporales, Polyporaceae)

Abstract

The aim of our research was to study the influence of citrate and sulfate of copper, manganese and zinc on the carbohydrates composition of biomass of the medicinal mushroom Trametes versicolor (L.) Lloyd. cultivated in a liquid medium. The studied strain of Trametes versicolor 353 was obtained from the Culture Collection of Mushrooms (IBK) from the M. G. Kholodny Institute of Botany, National Academy of Sciences of Ukraine. Citrates of copper, manganese and zinc were obtained from the Institute of Nanobiotechnologies and Resource Conservation of Ukraine, Kyiv. In this study we used glucose-peptone-yeast extract medium (GPY) with the following composition of (g/L): glucose – 25, peptone – 3, yeast extract – 3, K 2 HPO 4 – 1, KH 2 PO 4 – 1, MgSO 4 ∙ 7H 2 O – 0.25, distilled water – 1,000 ml; pH 6,5 (control medium). Cu 2+ (sulfate form or citrate form) were added to control medium in concentration 4 mg/L, Zn 2+ and Mn 2+ (sulfate form or citrate form) were added to control medium in concentration 1 mg/L. Mycelium was grown in a submerged culture on a rotary shaker (120 rpm) at 26 °C in 250 ml Erlenmeyer flasks, containing 50 ml of liquid medium. The biomass was harvested after 9 days of cultivation in the liquid medium. Monosaccharides and sugar alcohols was analyzed by high-performance liquid chromatography Agilent 1200 (Agilent technologies, USA). The results of our research demonstrated that the fraction of total carbohydrates from T. versicolor 353, which were cultivated on the control medium, consists of glucose (91.5%), galactose (1.9%), mannose (5.4%), fucose (0.6%) and xylose (0.7%). The adding of sulfate of zinc or copper to the liquid medium didn’t change the content of monosaccharides of T. versicolor 353 biomass relative to the control medium. At the same time, in the medium with citrate of zinc the amount of glucose increased and the amount of mannose decreased relative to the control medium. Xylose and fucose were not detected in this case. In mycelium of T. versicolor 353 that was cultivated in the medium with manganese sulfate or manganese citrate we detected a small amount of ribose. But the content of other monosaccharides didn’t change in the medium with sulfate of manganese. At the same time, the addition of citrate of manganese to the medium raised the amount of mannose and reduced the amount of glucose in the biomass of T. versicolor 353 relative to the control medium. Also copper citrate reduced the content of glucose in mycelium of T. versicolor 353 relative to the control medium. But in this case we detected mannitol and sorbitol in the biomass. This data indicates that synthesis of sugur alcohols in T. versicolor 353 depend on copper ions in bioactive forms of citrate.