Phytic Acid Dephosphorylation Coupled with Dissimilatory Iron Reduction in Sediment
To study the coupling effect between dissimilatory iron reduction(DIR)and organic phosphorus(OP)transforma-tion in sediments is of practical importance to further illuminate the mechanism for water eutrophication,control environmen-tal phosphorus pollution,and cope with the potential global phosphorus crisis.This study took the coupled environment effect between DIR and OP transformation in sediments as point of penetration and explored the feasibility of DIR in promoting the dephosphorylation of phytic acid.Firstly,the concentration of OP and Fe(Ⅱ)in the natural sediment of East Lake in Wuhan was monitored.The correlation analysis between their concentration indicated that Fe(Ⅲ)was gradually reduced to Fe(Ⅱ),accompany-ing with a decrease in OP concentration,in the early diagenetic process driven by organic matter degradation.This could dem-onstrate dissimilatory iron reduction might promote OP transformation in sediment.Then,the simulation microcosm system"dissimilatory iron reducing microflora(DIRM)+ferrihydrite+phytic acid(PA)"was established using the enriched DIRM from sediment,to study the degradation and transformation of phytic acid OP by dissimilatory iron reduction mediated by DIRM.The findings further confirmed that DIR could significantly facilitate PA dephosphorylation to produce PO43-,which would be a potential new mechanism for inducing water eutrophication.
dissimilatory iron reductionphytic aciddephosphorylationsedimentendogenous organophosphorus