Biosorption of metals by microorganisms is a promising technology to remove accumulated non-process elements in highly recycled biorefinery process water. Removal of these elements would enable greater water reuse and reduce the environmental impact of effluent discharge. A model lignocellulosic ethanol biorefinery wastewater was created based on pulp mill effluent. This generated a wastewater with an environmentally realistic high loading of dissolved natural organic matter (900 mg/l), a potentially important factor influencing metal biosorption. Analysis of feedstock and pulp mill effluent indicated that Mn and Zn are likely to be problematic in highly recycled lignocellulosic ethanol biorefinery process water. Therefore, the growth of several bacteria and fungi from existing collections, and some isolated from pulp mill effluent were tested in the model wastewater spiked with Mn and Zn (0.2 mM). Wastewater isolates grew the best in the wastewater. Metal uptake varied by species and was much greater for Zn than Mn. A bacterium, Novosphingobium nitrogenifigens Y88T, removed the most metal per unit biomass, 35 and 17 mg Mn/g. No other organism tested decreased the Mn concentration. A yeast, Candida tropicalis, produced the most biomass and removed the most total metal (38 % of Zn), while uptake per unit biomass was 24 mg Zn/g. These results indicate that microorganisms can remove significant amounts of metals in wastewater with high concentrations of dissolved natural organic matter. Metal sorption by autochthonous microorganisms in an anaerobic bioreactor may be able to extend water reuse and therefore lower the water consumption of future biorefineries.
Amanda J. Palumbo, Sean C. Taylor, Sarah L. Addison, Alison H. Slade, Chris N. Glover
Endothelial nitric oxide synthase polymorphism G298T in association with oxidative DNA damage in coronary atherosclerosis
Content Type Journal Article
Category Research Note
RAJESH G. KUMAR, Department of Genetics, Osmania Univers ... more
A micropropagation protocol was developed for multiplication of seedless lemon (Citrus limon L. cv. Kaghzi Kalan) using nodal explants. The maximum shoot regeneration was observed on low level of BAP (0.1 mg l−1) or kinetin (0.5 mg l−1). BA was recorded to be better than kinetin in terms of ... more
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