Vol.:(0123456789) 1 3 World J Microbiol Biotechnol (2017) 33:169 DOI 10.1007/s11274-017-2332-4 REVIEW Magnetic treatment of microalgae for enhanced product formation Lucielen Oliveira Santos 1  · Kricelle Mosquera Deamici 2  · Bruno Costa Menestrino 1  · Jaqueline Garda‑Bufon 3  · Jorge Alberto Vieira Costa 2   Received: 6 June 2017 / Accepted: 10 August 2017 / Published online: 22 August 2017 © Springer Science+Business Media B.V. 2017 Keywords Magnetic felds · Microalgae · Bioproducts Introduction Microalgae are a large and diverse group of aquatic organ- isms that lack the complex cell structures found in higher plants (Bowles 2007). Most species are photoautotrophic and convert solar energy into chemical forms through pho- tosynthesis (Slade and Bauen 2013). These microorganisms are considered very promising for multi-purpose biomass production because they can grow rapidly, produce large quantities of lipids, carbohydrates and proteins, sequester and recycle CO 2 from industrial fue gases and remove pol- lutants from industrial, agricultural and wastewaters (Hunt et al. 2009). Although the commercialized production of microalgal biomass, as healthy food and valued-added addi- tives is proftable, more efcient and inexpensive cultivation technique has been searched for (Zhang et al. 2015). Magnetic fields (MF) have been applied during the growth of diferent species of microorganisms and diferent results have been found. Researches with MF application have shown diferences in cellular behavior when cells are submitted to magnetic treatment. Its efect may be nega- tive or positive, and may include the acceleration of growth and changes in metabolism (Hunt et al. 2009). According to Yang et al. (2011), these modifcations depend on the intensity, frequency and the functional time. The potential link between MF and the efect caused on living organisms is due to the fact that it causes oxidative stress, i.e., the MF can alter the energy levels and orientation of the spin of electrons, thus increasing activity, concentra- tion and time life of free radicals (Repacholi and Green- ebaum 1999; Sahebjamei et al. 2007). Abstract Static or modulated magnetic felds (MF) may interact with the biological system and afect the metabolism of microorganisms, such as their photosynthetic capacity or synthesis of carbohydrates. Their efects on microorganisms, which can be classifed 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 efects of exposure to magnetic forces depend on magnetic intensity, frequency and exposure time. Modi- fcations in these parameters may enhance product forma- tion. Efects difer 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 fn- ished biomolecules, is a simple, inexpensive and powerful process. However, bioefects 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 appli- cation must be developed in order to obtain the best condi- tions for the production of molecules with high economic potential. * Lucielen Oliveira Santos santoslucielen@gmail.com 1 Laboratory of Biotechnology, Chemistry and Food School, Federal University of Rio Grande, Rio Grande, RS, Brazil 2 Laboratory of Biochemical Engineering, Chemistry and Food School, Federal University of Rio Grande, Rio Grande, RS, Brazil 3 Laboratory of Mycotoxin and Food Science, Chemistry and Food School, Federal University of Rio Grande, Rio Grande, RS, Brazil