The Effect of Humic Acids on Zymogenous Microbial Consortia Growth.

This paper describes experiments with standard humic acids (HA-S) and humic acids (HA) isolated from soil that was contaminated with mazut and treated with a consortium of microorganisms for the process of bioremediation (HA-E). Both acids inhibited the toxicity of ferric chloride and increased the growth of a zymogenous microbial consortia compared with controls. Electron paramagnetic resonance spectroscopy showed that HA-S and HA-E exhibit high anti-oxidative activity involving free radical scavenging and iron sequestration. HA additionally promote microbial consortium growth by providing protection from oxidative stress. [ABSTRACT FROM AUTHOR]