海洋深層水, 表層水及びそれらの混合海水におけるフェノールの分解性(In vitro degradation test of phenol in surface, deep, and mixed seawater)
- 標題
- 海洋深層水, 表層水及びそれらの混合海水におけるフェノールの分解性(In vitro degradation test of phenol in surface, deep, and mixed seawater)
- 作者
- 岩崎 誠二(Sejij Iwasaki)
- 文件屬性
- 日本研究
- 知識分類
- 基礎研究
- 出版年
- 2006
- 刊名
- 海洋深層水研究
- 卷
- 7
- 期
- 2
- 頁
- P 23-30
- 點閱數
- 2562
摘要
深層水に含まれる窒素・リン等栄養塩を利用したバイオレメディエーションの基礎実験として, 深層水, 表層水及びそれらの1: 1混合海水における1, 10及び100mgl-1のフェノール分解性の比較検討を行った.その結果, 上記の各種海水におけるフェノールの分解速度は, おおむね1: 1混合海水>深層水>表層水であった.1: 1混合海水では, 10mgl-1のフェノールは, 1日間の分解試験で, 90%以上分解された.細菌数は, 混合海水では初期値が104CFU ml-1のオーダーであったが, 2日間で106CFU ml-1程度まで上昇した.表層水は微生物数が多いが栄養塩類に乏しく, 深層水は栄養塩類が豊富であるが微生物数は少ない.1: 1混合海水では, 微生物及び栄養塩類を相互に供給する結果となり, 化学物質を分解する上で適切な系が形成されたと推測される.本結果から, 深層水の新たな利用方法として, 深層水を利用したバイオレメディエーションの可能性が示唆された.
Some heterotrophic bacteria in surface seawater (SSW), living on natural organic compounds such as sugars and lipids, can decompose artificial chemical substances. The enriched nature of deep seawater (DSW) may facilitate the activities of these bacteria. In the present study, degradation of one, ten and one hundred mg l-1 of phenol was compared in vitro among the four media, SSW, DSW, mixture of SSW and DSW (1: 1) and distilled freshwater. The DSW and SSW were pumped from depths of 440 and 0 m, respectively, in the Pacific Ocean off Owase, Mie Prefecture. Tested concentrations of phenol were degraded in SSW and DSW (but not in distilled freshwater) as follows: 1 mg l-1 of phenol was almost completely degraded in SSW, DSW and the mixture in two days; 10 mg l-1 of phenol was almost completely degraded in two days in DSW and the mixture, while degradation rate was less than 60 % in SSW; although 100 mg l-1 of phenol was not perfectly degraded in any seawater after five days, the degraded amounts of phenols increased unlike with lower phenol concentrations. Initial numbers of bacteria in SSW, DSW and the mixture were 89000, 530 and 41000 CFU ml-1, respectively. The number increased most in the mixture, attaining 106 CFU ml-1 during the period. These results suggested that the mixture of SSW (bacteria-rich, nutrientpoor) and DSW (bacteria-poor, nutrient-rich) was optimal and that the in situ release of DSW can be a good tool for enhancing bioremediation to degrade artificial chemical compounds.
Some heterotrophic bacteria in surface seawater (SSW), living on natural organic compounds such as sugars and lipids, can decompose artificial chemical substances. The enriched nature of deep seawater (DSW) may facilitate the activities of these bacteria. In the present study, degradation of one, ten and one hundred mg l-1 of phenol was compared in vitro among the four media, SSW, DSW, mixture of SSW and DSW (1: 1) and distilled freshwater. The DSW and SSW were pumped from depths of 440 and 0 m, respectively, in the Pacific Ocean off Owase, Mie Prefecture. Tested concentrations of phenol were degraded in SSW and DSW (but not in distilled freshwater) as follows: 1 mg l-1 of phenol was almost completely degraded in SSW, DSW and the mixture in two days; 10 mg l-1 of phenol was almost completely degraded in two days in DSW and the mixture, while degradation rate was less than 60 % in SSW; although 100 mg l-1 of phenol was not perfectly degraded in any seawater after five days, the degraded amounts of phenols increased unlike with lower phenol concentrations. Initial numbers of bacteria in SSW, DSW and the mixture were 89000, 530 and 41000 CFU ml-1, respectively. The number increased most in the mixture, attaining 106 CFU ml-1 during the period. These results suggested that the mixture of SSW (bacteria-rich, nutrientpoor) and DSW (bacteria-poor, nutrient-rich) was optimal and that the in situ release of DSW can be a good tool for enhancing bioremediation to degrade artificial chemical compounds.