Ability of Cupriavidus necator H16 to resist, bioremove, and accumulate some hazardous metal ions in water

Abstract

Bacterial biomasses are suitable and inexpensive biosorbents for the removal of metal ions. The Gram-negative betaproteobacterium Cupriavidus necator H16 is found in soil and freshwater environments. In this study, C. necator H16 was used to remove chromium (Cr), arsenic (As), aluminum (Al), and cadmium (Cd) ions from water. Minimum inhibition concentration (MIC) values of C. necator to Cr, As, Al, and Cd were found as 76, 69, 341, and 275 mg/L, respectively. The highest rates of Cr, As, Al, and Cd bioremoval were 45, 60, 54, and 78%, respectively. pH levels between 6.0 and 8.0 and an average temperature of 30 °C were optimum for the most efficient bioremoval. Scanning electron microscopy (SEM) images of Cd-treated cells showed that the morphology of the cells was significantly impaired compared to the control. Shifts in the Fourier transform infrared spectroscopy analysis (FTIR) spectra of the Cd-treated cell walls also confirmed the presence of active groups. As a result, it can be said that C. necator H16 has a moderate bioremoval efficiency for Cr, As, and Al and a high bioremoval efficiency for Cd. HIGHLIGHTS Cr, As, and Al removal capacities of Cupriavidus necator H16 strain are medium, and Cd removal capacity is high.; Bioremediation capacity is significantly influenced by metal concentration, pH, and temperature.; The functional groups were determined from FTIR spectra.; SEM micrographs showed that metal-treated cells were more deformed than control cells.; C. necator H16 can be used in various metal treatment processes.;

Keywords

• bioaccumulation
• bioremediation
• cupriavidus necator h16
• metals
• water environment