Effect of magnetic field on surface properties ofBacillus cereusCrA and its Extracellular Polymeric Substances (EPS)

Abstract

The effect of magnetic field on surface properties of Bacillus cereus CrA and its EPS was studied by zeta potential and FT-IR spectrum. The weak magnetic fields of 6.0-10.0 mT promoted the predominant strain B. cereus CrA to form EPS. The weak magnetic field of 2.4-10.0 mT could improve the bio-adsorption efficiency of anions by decreasing the negative charge of the intact strain, while the magnetic field of 17.4 mT could increase the negative charge of the strain's EPS by 20% and be responsible for the bio-adsorption of cations. Magnetic field could affect the band intensity and the slight shifting of peaks and the fluctuation of the bacterial absorption capability depended on the magnetic density. The magnetic field energy could affect the hydroxyl group and carboxyl group by forming hydrogen bonding, which were responsible for the adsorption ability of the strain and its EPS.

Characteristics of Nitrogen Removal and Extracellular Polymeric Substances of a Novel Salt-Tolerant Denitrifying Bacterium, Pseudomonas sp. DN-23

“…NaCl stress had little effect on the polysaccharide concentration of EPS, while a significant increase in protein concentration was observed during salt stress. Compared to what was described in the literature (Yan et al, 2013;Xu et al, 2014), the protein content of EPS was much higher, which may be due to the presence of a number of exoenzymes, as suggested by Frølund et al (1995). Additionally, the protein content increased under NaCl stress, which may result from cells producing more exoenzymes when cultivated in an unfavorable environment (Adav and Lee, 2008).…”

“…The zeta potential, flocculating efficiency, and auto-aggregation rates were then measured to quantitatively describe the aggregation performances. Zeta potential can be used to describe the electrostatic interactions between colloidal particles, which are important indicators of the stability of the colloidal system (Xu et al, 2014). In addition, the zeta potential is important for adsorption as it can indicate interactions between particles (Zadaka et al, 2010).…”

The production and application of bacterial exopolysaccharides as biomaterials for bone regeneration

“…However, for many species, such as Streptococcus thermophilus (Zisu & Shah, 2003), an acidic stress can increase EPS production. Other factors influencing EPS production have been explored, such as the presence of light for symbiotic and photosynthetic strains (Zisu & Shah, 2003), microwave radiation (Kothari et al, 2014;Kushwah et al, 2013), magnetic field (Xu et al, 2014) and sound frequencies (Sarvaiya & Kothari, 2015;Shah et al, 2016). Culture parameters can also influence the composition and MW of the produced EPS.…”

“…Culture parameters can also influence the composition and MW of the produced EPS. For example, the pH and temperature of culture both influenced sugar composition, acyl group composition and MW of the EPS in Enterobacter A47 (Torres et al, 2012), and magnetic field changed both the charge and adsorption properties of an EPS from Bacillus cereus CrA (Xu et al, 2014).…”

The weak magnetic field (WMF) enhances the stimulation of polymyxin B sulfate (POL) on Vibrio qinghaiensis sp.-Q67

“…Till now, scientists have not reached a consensus on how living organisms reacting to this complicated circumstance, such as magnetic field, solar activity indices, temperature, humidity, atmospheric pressure, geomagnetic conditions, etc. [4,33,58,61,66,72,76].…”