A comparison of sodium sulfate, sodium phosphate, and boric acid for preparation of immobilized Pseudomonas putida F1 in poly(vinyl alcohol) beads

Abstract

Poly(vinyl alcohol) (PVA) gel beads crosslinked with sodium phosphate or boric acid have been widely utilized for microorganism immobilization. We previously utilized sodium sulfate to induce crosslinking of PVA for preparing immobilized yeast cells in PVA beads. In this study, we compared the toxicities of sodium sulfate and conventional crosslinkers (sodium phosphate and boric acid) toward Pseudomonas putida F1 (PpF1) and the performance of the corresponding immobilized PpF1 in PVA beads. The toxicity of sodium sulfate to PpF1 was lower than those of the conventional crosslinkers. PVA-sodium sulfate beads showed a higher gel fraction of PVA and a lower swelling ratio in water than PVA-sodium phosphate beads, which indicates that the former had higher stability. PpF1 immobilized in the PVA-sodium sulfate beads completely degraded the pollutant trichloroethylene (TCE) with an initial concentration (0.42 mg/l) within the most common range of TCE concentration found in contaminated field sites.

Shape Stable Poly(vinyl alcohol) and Alginate Cross-Linked Hydrogel under Drying-Rewetting Cycles: Boron Substitution

“…The degree of boron substitution (Figure ) is highly correlated with the stability of the yielded) hydrogels (Figure )). The second cross-linking reaction, however, is not a fast reaction, as evidenced by the results in Figure and by the observations of Zain et al and Takei et al, which revealed that hydrogel stability can be increased by increasing the concentration of applied nucleophiles and contact time.…”

Enhanced fermentative hydrogen production using gamma irradiated sludge immobilized in polyvinyl alcohol (pva) gels

“…Suspended sludge showed higher maximum hydrogen production at different temperature conditions than immobilized sludge, indicating that hydrogen producers in suspended state can better adapt to the temperature change. Yoshida et al also found that temperature had greater influence on the sodium alginate immobilized sludge than the suspended sludge [50]. Figure 1b shows that hydrogen yield by suspended sludge increased with increasing temperature, and highest hydrogen yield of 1.92 mol H 2 /mol glucose was obtained at 408C.…”

“…Quite a few studies have observed temperature effects on hydrogen production by immobilized cells. Yoshida et al also found that temperature had greater influence on the sodium alginate immobilized sludge than the suspended sludge [50]. Seol et al obtained highest hydrogen production at 37.58C, and observed 14-57% decrease in cumulative hydrogen production when temperature ranged from 20 to 458C [49].…”

Preparation and properties of a poly(vinyl alcohol) hydrogel‐melamine formaldehyde foam composite

“…The physical crosslinking gel is usually obtained through repeatedly freezing and thawing a PVA solution . This method can avoid using some hazardous materials such as boric acid , aldehydes , and so forth, which are conventional crosslinking agents for PVA in the chemical gelation process. Therefore, the physical hydrogel is absolutely harmless to microorganisms and the manufacture process is also eco‐friendly.…”