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The effect of gluconic acid secretion by phosphate-solubilizing Pseudomonas putida bacteria on dissolution of pyromorphite Pb5(PO4)3Cl and Pb remobilization

Topolska J., Borowicz P., Manecki M., Bajda T., Kaschabek S., Merkel B. J.

Annales Societatis Geologorum Poloniae

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2013

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Vol. 83, No. 4

343--351

EN

The purpose of this study was to investigate the effect of bacterially produced gluconic acid on the dissolution of pyromorphite and Pb remobilization. Pyromorphite Pb5(PO4)3Cl is formed as a product of the phosphate-induced treatment of Pb-contaminated sites. This very stable mineral greatly decreases the bioavailability of Pb. In this study, bacterial and abiotic batch experiments on the dissolution of pyromorphite were carried out. In the microbial experiments, the mineral was dissolved in the presence of the phosphate–solubilizing soil bacterium, Pseudomonas putida. The bacterial growth medium was supplemented with glucose, which under natural condi- tions can be supplied to microbes via symbiosis with plants. P. putida acquired P from pyromorphite and enhanced its dissolution. Elevated Pb concentrations were observed in the suspensions with bacteria. The bacterial secretion of 16.5 mM gluconic acid played a significant role in Pb remobilization; the pH of the solution dropped down from an initial 7.4 to 3.5. In the abiotic experiments, pyromorphite was dissolved at several concentrations of gluconic acid and at an acidic to neutral pH range. Both acidification and formation of stable Pb-gluconate ligands enhanced the dissolution of pyromorphite and caused Pb remobilization.

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Katalizatory Pd-Te/nośnik do selektywnego utleniania glukozy do kwasu glukonowego w fazie ciekłej

Witońska I., Karski S., Frajtak M.

Przemysł Chemiczny

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2011

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T. 90, nr 3

475-480

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Optimization of macroelements in synthetic medium with saccharose and glusose for potassium gluconate bioproduction

Podgórski W., Foryś E.

Inżynieria i Aparatura Chemiczna

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2005

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Nr 4s

81-82

EN

The replicated 23 full factorial central composite circumscribing quadratic design of experiments has assisted to determine the optimum medium composition for gluconic acid biosynthesis that was as follows: 0.12 g dm-3 - NH4NO3, 0.64 g dm-3 -KH2P04 0.48 g dm-3 - MgSO4-7H2O. Using 150 g dm-3 of saccharose and glucose the product of 76.3 g dm-3 and 136.3g dm-3 was obtained, respectively.

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Kinetyczny model wzrostu Aspergillus niger W78B w okresowym procesie biotransformacji glukozy do kwasu glukonowego

Podgórski W.

Inżynieria i Aparatura Chemiczna

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2005

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Nr 4s

79-80

EN

The growth process of Aspergillus niger W78B during batch biotransformation of glucose into gluconic acid was studied. A simple model of the Contois equation was proposed as the best representation of main effects influencing biomass growth. It assumes that growth of Aspergillus niger W78B mainly depends on glucose and biomass concentration in the medium.