feldspar and gluconic-acid

Bacteria play important roles in mineral weathering and soil formation. However, little is known about the nutrition-related changes in mineral weathering potential and pattern of bacteria. In this study, mineral weathering behaviors of a novel mineral-weathering bacterium Chitinophaga jiangningensis JN53 were characterized in the presence of three contrasting biotite or potassium feldspar-added media. C. jiangningensis JN53 increased more Fe release from the minerals in the M-BHm (nutrition-poor medium) than in the SSKM (nutrition-rich medium) and BHm (nutrition-moderate medium), while C. jiangningensis JN53 released more Al from the minerals and Si from biotite in the SSKM. Similar Si release from potassium feldspar by C. jiangningensis JN53 was observed in the SSKM, BHm, and M-BHm. K releasing ability of C. jiangningensis JN53 was significantly higher in the biotite-added M-BHm. Highest and lowest growth of C. jiangningensis JN53 was observed in the SSKM and M-BHm, respectively. In the presence of the minerals, C. jiangningensis JN53 mainly produced gluconic acid in the SSKM and acetic acid in the BHm and M-BHm. C. jiangningensis JN53 also produced large amount of succinic acid in the biotite-added SSKM and oxalic acid in the potassium feldspar-added M-BHm. The results showed the growth, production of organic acids, and mineral weathering ability of C. jiangningensis JN53 in the three contrasting nutrition conditions. The results also suggested the change in the mineral weathering behaviors of C. jiangningensis JN53 under different levels of nutrition conditions.

Topics: Acetic Acid; Aluminum; Aluminum Silicates; Bacteroidetes; Culture Media; Gluconates; Minerals; Oxalic Acid; Potassium Compounds; Silicon; Soil Microbiology; Succinic Acid

A silicate mineral-solubilizing bacterial strain Q12 was isolated from the surfaces of weathered feldspar and identified as Bacillus globisporus Q12 based on the 16S rDNA gene sequence analysis. Three silicate minerals (feldspar, muscovite, and biotite) were used to investigate potassium and silicon mobilization by strain Q12. In liquid cultures, the strain showed better growth on the biotite than on feldspar and muscovite. The biotite was the best potassium source for growth of the strain. Solubilization of potassium and silicon from the silicate minerals by the strain resulted mostly from the action of organic acids. Gluconic acid seemed to be the most active agent for the solubilization of the 3 silicate minerals. Gluconic and acetic acids were likely involved in the solubilization of feldspar. The strain could be acid or alkali and salt tolerant and temperature resistant.

Topics: Acetic Acid; Aluminum Silicates; Bacillus; DNA, Bacterial; Ferrous Compounds; Gluconates; Molecular Sequence Data; Potassium; Potassium Compounds; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Silicon