Effect of modulated microwave frequencies on the physiology of a cyanobacterium, Anabaena doliolum

The effect of microwave modulated with square waves of different pulse repe tition frequencies was studied on the physiologic behavior of the cyanobact erium Anabaena doliolum. The organism was exposed either directly after ino culating the nutrient solution or indirectly by exposing the nutrient solut ion before inoculation with the cyanobacterium cells for 1 h to microwave ( 9.575 GHz) modulated with square wave pulse repetition frequencies of 1000, 700, 500, 200, 100, and 50 Hz at a fixed incident power density (0.658 mW/ cm(2)). This study reveals that microwaves athermally induce different biol ogic effects, perhaps by changing the structures of water. Modulation frequ ency-de pendent water structures appear to cause the biologic effects by di fferentially partitioning the ions, altering the rate and/or directions of biochemical reactions, or other mechanisms.