Solubilization of silicate from quartz mineral by potential silicate solubilizing bacteria (Pelarutan silika asal mineral kuarsa oleh bakteri pelarut silika potensial )

Abstract

AbstrakSilika (Si) AbstractSilicon (Si) is the second most abundant in the soil varies from 50 to 400 g Si per kg of soil. Silicon has positive influence on the plant resistance to various abiotic and biotic stressors such as salinity, drought, heavy metal toxicities and diseases. Although Si is abundant in soil, most of its sources are not available for plant uptake due to low solubility of Si compounds in soil. To improve plant-available Si in the soil, silicate solubilizing bacteria (SSB) are potentially important in solubilizing insoluble forms of silicate. The objectives of this study were to determine: (i) silicate solubilizing activity of Burkholderia cenocepacia KTG, Aeromonas punctata RJM3020, and B. vietnamiensis ZEO3 on magnesium trisilicate and quartz, (ii) biochemical characteristics of SSB, and (iii) solubilization of silicate, Ca, and Mg from quarts by SSB activity. A laboratory study was conducted at Microbiology and Environment Laboratory, the Indonesian Research Institute for Biotechnology and Bioindustry, Bogor, in 2016. All SSB were grown on Bunt and Rovira media containing 0.25% magnesium trisilicate or quartz as substrate, respectively. Silica solubilizing activities by SSB were determined by using inductively coupled plasma-atomic emission spectrometry while organic acid concentration in the culture were measured by using highperformance liquid chromatography (HPLC

The Opportunity of Spent Bleaching Earth (Bentonite) and Silica Solubilizing Bacteria as Silica Source for Induction of Secondary Metabolites Production in Plants

“…The inoculation of silica solvent bacteria in some natural silicates not only dissolves silica but simultaneously releases phosphorus and potassium (Meena et al, 2014). In addition, silica solvent bacteria are also confirmed to increase the solubility of elements Ca and Mg as secondary nutrients (Santi & Goenadi, 2017).…”

“…This is because some of the silica in the soil is not available to plants. After all, Si's solubility in the soil is relatively low (Santi & Goenadi, 2017). In addition, the decline of Si in the soil can occur in intensive cultivation practices and continuous sustainable monoculture cultivation.…”

“…Inoculation tests of silica solvent bacteria strains with silica minerals (magnesium tricyclic and feldspar) showed that Bacillus mucilaginous and Pseudomonas are the best silica solvent bacteria, characterized by the formation of clear zones around bacterial growth (Vasanthi et al, 2018). Bacteria in the soil can dissolve unavailable silica such as quartz by removing organic acids and directly dissolve potassium rocks or silica chelate ions to bring potassium and silica into solution (Santi &Goenadi, 2017).…”

“…Three selected strains of silica solvent bacteria from Santi and Goenadi's study (2017) acetic acid, and oxalic acid. Burkholderia cenocepacia strain has a high ability to produce acetic acid, while Aeromonas punctata strain can produce citric acid and oxalic acid (Santi & Goenadi. 2017).…”

“…In addition to organic acid production, silica solvent bacteria also release silica by producing extracellular polysaccharides (EPS) (Liu et al, 2006) and exopolysaccharides (Santi &Goenadi., 2017). The B. eburnean isolate has been shown to produce acetic indol acid (AAI) that stimulates root hair initiation.…”