Journal of The School of Marine Science and Technology,Vol.9 No.3
Study on acclimatization of a marine gram-negative aerobic bacterium
in the high concentrations of formaldehyde
Hiroshi ISHII, Takafumi MAEDA, Ryoichi INOUE and Hiroshi SAITO
Abstract
Formaldehyde is a toxic chemical that has recently been discharged as an effluent from industrial wastewater into the marine environment. High concentration of formaldehyde in the marine environment could possibly have detrimental effect on the lives of many aquatic organisms, since formaldehyde is known to cause damage to DNA and mutations in microorganisms and mammalian cells. Therefore, it’s necessary to develop an effective method for removal of the formaldehyde from wastewater. In the present work, we focused on the isolation of bacterial strains and characterization of their adaptability to high concentrations of formaldehyde.
We investigated the formaldehyde acclimatization mechanisms in the SMM-7 strains, which were isolated from seawater in the mouth of the Tomoe River. Effects of high concentrations of formaldehyde on the bacteria were determined through following two steps: 1） the strain was cultured in nutrient broth medium with different concentrations of formaldehyde up to 300 ppm, 2） the cultured bacteria grown in the formaldehyde concentration of 300 ppm was further cultured in a series of higher concentrations of formaldehyde （500 ppm, 750 ppm, 1,000 ppm）. The bacterial strains were noticed to acclimate to up to 750 ppm of formaldehyde. These results indicated that SMM-7 pre-adapted to formaldehyde was able to grow in more high formaldehyde concentration.