Filamentous Fungi and Yeasts as Sources of Coenzyme Q10 and Its Applications

Coenzyme Q or CoQ is also known as ubiquinone is a benzoquinone that is present in human, animals and most living beings but its isoprene units varies in different living entities ranging from CoQ6 to CoQ10, It is a polyphilic molecule containing hydrophobic isoprenoid chains attached to benzoquinone ring. In humans it is present as CoQ10 containing ten isoprene units, situated in mitochondrial inner membrane and plays an important role in energy generation and free radical scavenging. Due to supportive therapeutic benefits of CoQ10 in humans, it is considered as an industrially important molecule having nutraceutical, pharmaceutical and cosmeceutical applications. Different routes for its synthesis have been tried for commercial production, like chemical and biological, but the later one is preferred. The biological synthesis involves large scale fermentation and extraction of this molecule from CoQ10 containing microbes; hence the process demands the use of microbial strains with high productivity and yields of CoQ10. Studies carried out on the microbial synthesis of CoQ10 over many decades mainly focus on use of bacterial and yeast strains having endogenous biosynthetic pathway for ten isoprene units containing CoQ production. The yields of native CoQ10 have been increased to meet commercial requirements by mutations, fermentation process improvements and metabolic engineering. Attempts have also been made to express the pathway genes in other suitable, non-CoQ10 producing strains to finally synthesize CoQ10. Although, CoQ10 is synthesized using bacterial as well as fungal strains, the fungal source is preferred as CoQ10 biosynthetic pathway of yeast and human is very similar as opposed to bacterial pathways. The CoQ10 from a eukaryote has more similarity in terms of functionality with human CoQ10 and high degree of conservation with a mammalian species. Therefore, commercial production of CoQ10 using fungi/yeast is most preferred and highlights its importance. This review explains the properties, functions of CoQ10, its biosynthesis from the wild as well as recombinant strains and the physiological significance of CoQ10 in human wellbeing.