With the development of the electric technologies, the biological effects of electromagnetic fields (EMF) were widely studied. However, the results remain controversial and the biophysical mechanisms are still unknown. To our knowledge, little studies pay attention to the radio frequency (RF) of 2.6–5 MHz. In the present study, we investigated the effect of these radio frequencies on the growth and cell viability of Saccharomyces cerevisiae at very low power density below 0.1 mT. The result appeared to be time-dependent. The growth of the yeast cells was obviously affected by the RF-EMF with a 43.5% increase when exposed for 30 h, and the growth-promoting effect decreased along with the radiation time and eventually turned to an inhibiting effect retarding growth by 20.7% at 89 h. The cell viability was improved to 70.1% at 8 h and reduced by 33.5% at 28 h. The superoxide accumulated in exposed cells as radiation time increased which may lead to the inhibition of viability and growth of the cells. However, the efficient frequency, power density, and exposure dosage await further investigation. Nevertheless, the wave band studied in this research is effective to produce biological effect, and therefore, it may provide an optional new radio frequency which is valuable for the development and utilization in therapy technique and medical use.

中文翻译：

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射频诱导的超氧化物积累影响了酿酒酵母的生长和生存能力。

随着电子技术的发展，电磁场（EMF）的生物效应得到了广泛的研究。但是，结果仍存在争议，其生物物理机制仍未知。据我们所知，很少有研究关注2.6-5 MHz的射频（RF）。在本研究中，我们研究了这些射频对酿酒酵母生长和细胞活力的影响。低于0.1 mT的极低功率密度。结果似乎与时间有关。暴露30 h后，RF-EMF对酵母细胞的生长有明显的影响，增长了43.5％，促进生长的作用随着辐射时间的延长而逐渐减弱，最终变成抑制作用，使酵母细胞的生长延长了20.7％。 89小时 细胞活力在8 h时提高到70.1％，在28 h时降低了33.5％。随着辐射时间的增加，暴露于细胞中的超氧化物会累积，这可能导致细胞活力和细胞生长受到抑制。但是，有效频率，功率密度和暴露剂量有待进一步研究。尽管如此，本研究中研究的波段仍可有效产生生物学效应，因此，