Plasma-based stimulation of biotechnological processes in Ganoderma lucidum mycelia as example for a eukaryotic organism

摘要

In biotechnological processes, high-yielding production strains are the condition for economic production of biomass and desired metabolites. Plasma with its components like UV radiation and highly reactive radicals could possibly generate and improve new production strains. Indeed, plasma was able to generate high-yielding bacterial strains. A candidate for eukaryotic cells for improving metabolite production is the medicinal mushroom Ganoderma lucidum used for prevention and treatment of many different diseases. Mycelia and fruit bodies contain more than 150 structurally different triterpens. The aim of our investigation was to check whether plasma influences growth and productivity of the fungus. Mycelial cultures were exposed to plasma for 2–20 min by using three different plasma sources: the plasma jet kINPen 09 and two dielectric barrier discharge plasma sources (surface-DBD, volume-DBD). Yield of biomass and extracts were determined. HPLC fingerprints of organic extracts were recorded. Content of triterpens, ganoderic acid A, ergosterol, and β-1-3 d-glucan was determined. Volume-DBD increased extract yield and β-1-3 d-glucan content, while whole triterpenoid content was increased by the plasma jet. Both dielectric barrier discharge plasma sources led to elevated ergosterol contents. The effects seemed to be related to energy input by the plasma sources. In conclusion, plasma could be principally useful for optimization of biotechnological processes not for only prokaryotic but also eukaryotic cells.