Immobilization of Mn(II) Ions by a Mn-Oxidizing Fungus Paraconiothyrium sp.-Like Strain at Neutral pHs
A Mn-oxidizing fungus was isolated from a constructed wetland of Hokkaido (Japan), which is receiving the Mn-impacted drainage, and genetically and morphologically identified as <I>Paraconiothyrium sp.</I>-like strain. The optimum pHs were 6.45–6.64, where is more acidic than those of previously reported Mn-oxidizing fungi. Too much nutrient inhibited fungal Mn-oxidation, and too little nutrient also delayed Mn oxidation even at optimum pH. In order to achieve the oxidation of high concentrations of Mn like mine drainage containing several hundreds g·m<SUP>−3</SUP> of Mn, it is important to find the best mix ratio among the initial Mn concentrations, inoculumn size and nutrient concentration. The strain has still Mn-tolerance with more than 380 g·m<SUP>−3</SUP> of Mn, but high Mn(II) oxidation was limited by pH control and supplied nutrient amounts. The biogenic Mn deposit was poorly crystallized birnessite. The strain is an unique Mn-oxidizing fungus having a high Mn tolerance and weakly acidic tolerance, since there has been no record about the property of the strain. There is a potentiality to apply the strain to the environmental bioremediation.
- Materials transactions
Materials transactions 47(10), 2457-2461, 2006-10-20