Nonthermal Effects of Millimeter Microwaves on Yeast Growth

Abstract

Weak microwave irradiation of aqueous yeast cultures was found to affect their growth rate in a frequency-selective manner. Depending on frequency (near 42 GHz), both increases and de­ creases of the growth rate were observed. The resonance bandwidths are of the order of 0.01 GHz. Simple thermal effects can be excluded. These findings support theoretical predictions of coherent molecular oscillations activating metabolic processes.

Studies on possible genetic effects of microwaves in procaryotic and eucaryotic cells

“…Interesting results on microwave effects on cellular growth were obtained in this range, showing a frequency dependence (Webb and Dodds, 1968;Berteaud et al, 1975). Recently, a more specific frequency dependent response on cellular growth rate has been demonstrated (Grundler et al, 1977;Grundler and Keilmann, 1978;Keilmann and Grundler, 1980). Such a response, especially in a resonant form of the biological system may point to special mechanisms non uniform with thermal influence (Grundler, 1981).…”

Interactions of Science, Technology and Medicine: Electromagnetic Radiation During the Twentieth Century

“…Grundler et al (1977Grundler et al ( , 1988, Grundler and Keilmann (1978) studied the growth behavior of yeast cultures under coherent microwave irradiation. to avoid thermal effects of irradiation he chose to use a yeast cell culture in stirred aqueous suspension, as this assures an efficient thermal exchange between the cells and the surrounding medium.…”

The Influence of Low-intensity Millimeter-Wave Radiation on the Growth of Cress Roots

“…6 . Local power density of the microwave field for both polarizations (E|| and E ± ) in positions along the vertical axis in the plane of the roots (s. inset) as determined by switching the radiation on and off and measuring the microwave-induced temperature rise AT in the small absorber piece.…”