Mercury bioremoval from water by probiotics in simulated microgravity

Heavy metals contamination is one of the major concerns of food industry professional's foodstuffs. So that, they are looking for a safe, cheap, easy and efficient method to eliminate this type of pollution. There are studies that reported the bioremoval of some heavy metals by probiotics from water and foods. Mercury (Hg) is one of the most dangerous heavy metals and its decline is a serious environmental management effort. Due to safety and several other advantages of probiotic bacteria including their ability to heavy metal binding and adsorbing, there are a lot of tendency to employing them for bioremoval of heavy metals. Earth gravity is an effective force under which life appeared and developed. There are several studies about the effect of microgravity on living organisms, including microorganisms. In the current research, capability ofLactobacillus acidophilus for mercury ions bioremoval from water was assessed in microgravity conditions. In addition, thermal and alkaline pretreatment effect on Hgabsorption power of L. acidophilus was evaluated. Furthermore, effects of simulated gastrointestinal were assessed on strength of L. acidophilus-Hg binding. Theresults demonstrated that L. acidophilus can decrease Hg concentration excellently in both conditions of simulated microgravity and normal gravity. In addition,L. acidophilus-Hg complex remained well stable under simulated gastrointestinal conditions, although the bond strength was higher in microgravity. Alkaline and heatpretreatment of L. acidophilus has not positive effects on the binding as well as stability, especially in microgravity, however, the stability was less in normal gravity.

Keywords:

“mercury” , “Heavy metal” , “microgravity , “Lactobacillus acidophilus”.