Wang et al. [30] used a magnetic field concentrated to a small area and observed that it helped to regulate the anti-oxidant defense system of Chlorella vulgaris at a threshold magnetic flux intensity of 10-35 mT. The authors proposed that this is probably due to the free radicals altered by the magnetic field, which accelerated the relative biologi­cal reactions. The analysis of hydroxyl radical (-OH) showed that it increased simultaneously with increasing magnetic flux density sug­gesting an oxidative stress induced by the exposure compared to the control.

6.3.1.3.2 BIODEGRADATION

A study using airlift reactors showed that the influence of magnetic fields enhanced the degradation of phenolic waste liquors by submersed micro­organisms at a magnetic field intensity of 22 mT [23].