Update on the application of magnetic fields to microalgal cultures

Coenzyme Q₁₀ (CoQ₁₀) is the main CoQ species in human and is used extensively in food, cosmetic and medicine industries because of its antioxidant properties and its benefit in prophylactic medicine and therapy for a variety of diseases. Among various approaches to increase the production of CoQ₁₀, microbial fermentation is the most effective. As knowledge of the biosynthetic enzymes and regulatory mechanisms modulating CoQ₁₀ production increases, opportunities arise for metabolic engineering of CoQ₁₀ in microbial hosts. In this review, we present various strategies used up to date to improve CoQ₁₀ production and focus on metabolic engineering of CoQ₁₀ overproduction in microbes. General strategies of metabolic engineering include providing sufficient precursors for CoQ₁₀, increasing metabolic fluxes, and expanding storage capacity for CoQ₁₀. Based on these strategies, CoQ₁₀ production has been significantly improved in natural CoQ₁₀ producers, as well as in heterologous hosts.

     

Magnetic treatment of microalgae for enhanced product formation

Static or modulated magnetic fields (MF) may interact with the biological system and affect the metabolism of microorganisms, such as their photosynthetic capacity or synthesis of carbohydrates. Their effects on microorganisms, which can be classified into inhibiting, stimulating and null, may be interpreted as the result of stress that cells undergo, thus, leading to responses through the same mechanisms. Biological effects of exposure to magnetic forces depend on magnetic intensity, frequency and exposure time. Modifications in these parameters may enhance product formation. Effects differ according to the form and application of MF characteristic parameters. Magnetic treatments have the advantages of being convenient and non-toxic, having low running cost, emitting no secondary pollution, enabling wide application and being easily shielded. MF application to the cultivation of microalgae, to improve the production of finished biomolecules, is a simple, inexpensive and powerful process. However, bioeffects of MF on microalgae need to be further investigated because there have currently been very few available reports in the literature. Thus, studies which aim at optimizing parameters involved in MF application must be developed in order to obtain the best conditions for the production of molecules with high economic potential.