The large-scale process of microbial carbonate precipitation for nickel remediation from an industrial soil

Soil bacteria that precipitate calcium carbonate: mechanism and applications of the process

“…Precipitation of calcium carbonate induced microbiologically (MICP) refers to the formation of calcium carbonate from an oversaturated solution due to the presence of microorganisms and their biochemical activities (Bosak, 2011). During MICP, organisms secrete one or more metabolic products ) that react with ions (Ca 2+ ) found in the environment with subsequent mineral precipitation (Zhu, Li, Zhan, Huang, Zhang & Achal, 2016b); such substances act as cementing materials and are commonly known as "biocement" (Rong, Qian & Li, 2012). Several works have demonstrated the existence of mechanisms that form calcium carbonate such as photosynthesis (McConnaughey et al, 1997), urea hydrolysis (De Muynck, Verbeken, De Belie, & Verstraete, 2010b;Dhami, Reddy & Mukherjee, 2013b;Galinat & Bang, 1999a;, anaerobic sulfides oxidation (Warthmann, Van Lith, Vasconcelos, McKenzie & Karpoff, 2000), and by extracellular polymeric substances (Arias & Fernández, 2008;McConnaughey et al, 1997).…”

“…On the other hand, alternatives have also been used to replace nutrients such as Torula yeast (Cyberlindnera jadinii), brewery waste yeast, Vegemite® and acetate (which lowered production costs by 95 %, achieving a level of ureasic activity of 21 mM hydrolyzed urea.min -1 ) (Wiffin, 2004), fermented maize liquor (obtaining higher calcium carbonate concentrations and lower water penetration values) (Achal, Mukherjee & Reddy, 2011a), and lentils (Zhu et al, 2016b). Although it is still necessary to implement the use of available economical and agroindustrial waste to reduce culture medium costs.…”

Povećanje učinkovitosti bioremedijacije na razini gena

“…Pomoću genske sekvencije dobivene primjenom te metode može se identificirati nova vrsta mikroorganizma koja aktivno sudjeluje u bioremedijaciji okoliša, a koju bi bilo nemoguće identificirati pomoću nemolekularnih tehnika. 43,44 Gen 16S rRNK upotrebljava se za filogenetska istraživanja jer je upravo taj gen evolucijski dobro očuvan te se razlikuje između raznih vrsta bakterija i arheja. 45,46 Ta je metoda značajno unaprijedila istraživanje mikrobne bioremedijacije jer se pomoću nje mogu pratiti promjene mikrobnog sastava praćenjem prisutnih vrsta tijekom različitih stadija procesa bioremedijacije.…”

Fungal nanoscale metal carbonates and production of electrochemical materials

“…Fungal biomineralization of carbonates results in metal removal from solution or immobilization within a solid matrix providing a method for detoxification as well as recovery (Table 1). Biologically-induced mineralization (BIM) involving urea hydrolysis by urease-positive microorganisms, which leads to metal carbonate precipitation, has been found to be effective in immobilizing several potentially toxic metals, for example Cd, Ni, Pb, Sr, and the metalloid As (Achal, 2012;Achal et al, 2012;Li et al, 2014Li et al, , 2015aZhu et al, 2016a). Urease-positive fungi, such as N. crassa, have the ability to precipitate metal carbonates in the media and around the biomass when incubated in urea-amended media while culture supernatants also provide a biomass-free carbonate bioprecipitation system (Li et al, 2014(Li et al, , 2015a.…”