Effects of extremely low frequency magnetic field on production of mannatide by α‐hemolytic Streptococcus

Abstract

The effect of the extremely low frequency magnetic field (ELF-MF) on biomass and mannatide production by α-hemolytic Streptococcus in liquid-state fermentation culture medium was studied during shake flask culture. Magnetic field (MF) inductions, exposure times, and exposure periods varied in a range of 0-1.5 mT, 0-16 h, and six periods of incubation time, respectively. Results showed both biomass and mannatide production increased significantly at MF induction 0.4, 0.6, and 0.9 mT and decreased at both 1.2 and 1.5 mT. Biomass increased by exposure for initial and middle stages of fermentation. Mannatide production increased significantly at 4-8, 8-12, and 17-21 h. Peak yield of biomass and mannatide production increased by 10.7% and 14.0% at 25 and 27 h of incubation at 0.6 mT MF induction and exposure to 8-12 h of incubation time, compared with the control experiment, respectively. ELF-MF could also enhance the growth rate and mannatide production rate of α-hemolytic Streptococcus. However, ELF-MF did not alter α-hemolytic Streptococcus cell growth and mannatide metabolizing regulation or fermentation pattern. Mannatide production was not associated with cellular growth but rather only partially associated. Bioelectromagnetics. 37:331-337, 2016. © 2016 Wiley Periodicals, Inc.

Low‐Frequency Magnetic Field of Appropriate Strengths Changed Secondary Metabolite Production and Na+ Concentration of Intracellular and Extracellular Monascus purpureus

“…Actually, there were many reports about the effects of the magnetic field on microbial metabolism. Mannatide production by α‐hemolytic Streptococcus is obviously enhanced after exposure to 0.4, 0.6, and 0.9 mT LF‐MF [Zhang et al, 2016]. The magnetic field also could raise citric acid accumulation by Aspergillus niger [Gao et al, 2011].…”

Global gene expression changes reflecting pleiotropic effects of Irpex lacteus induced by low‐­intensity electromagnetic field

“…However, no effects were identified in the gene expression when Schwenzer et al [] utilized SMF (3 T) in human embryonic lung fibroblasts or when Chen et al [] applied extremely low‐frequency magnetic fields (ELF‐MF) (0.4 mT, 50 Hz) to Saccharomyces cerevisiae . We speculated that the influence of EMF on the global gene expression changes was related to not only EMF induction but also some physical parameters (EMF type, frequency, exposure time, and duration of EMF), biological samples, and bacterium [Zhang et al, ]. The biomass of the I. lacteus mycelium was effectively promoted by LI‐EMF during fermentation in a previous study.…”

“…Many metabolic pathways are described as being regulated by an MF. ELF‐MF increases the citric acid and cellulose production of A. niger [Gao et al, ], mannatide production of α‐hemolytic Streptococcus [Zhang et al, ], and pigment production of Monascus purpureus [Zhang et al, , ]. Moreover, ELF‐MF could decrease citrinin production, a type of mycotoxin, and at the same time, could increase yellow, red, and orange pigment and monacolin K production in M. purpureus [Wan et al, ].…”

The Hyperfine Coupling Radical Pair Mechanism of Biological Effects on Weak Magnetic Fields

“…An increased risk of amyotrophic lateral sclerosis (ALS) in workers occupationally exposed to ELF-MFs were observed in Huss, et al [21]. Kleijn, et al [22]; Zhang, et al [23]; Schüz, et al [24]; Tang, et al [25]; Fixler, et al [26]; Wang, et al [27]; Prato, et al [28]; Corbacio, et al [29]; Vanderstraeten and Gillis [30]; Bowman, et al [31]; Prato, et al [32]; Burda, et al [33]; Burger, et al [34] reported the other biological effects of ELF-MFs (0 to 300 Hz) fields. Smith, et al [58]; Lednev [59]; Blanchard and Blackman [60]; Binhi [61] proposed the mechanisms of biological effects of ELF-MFs which are cyclotron resonance theory and it's new interpretation,the ion parametric resonance model and an interference of ions bound within proteins.…”

“…For example, more and more people have been attracted by the small increases in childhood leukemia for children living near power lines and possible increases in brain tumors for heavy use of cell phones [1]. The biological effects of extremely low-frequency (0 to 300 Hz) magnetic fields (ELF-MFs) are presented [21][22][23][24][25][26][27][28][29][30][31][32][33][34]. The biological effects of intermediate frequency (300 Hz to 100 kHz) magnetic fields(IMF-MFs)are discussed [35][36][37][38].…”