碩士 / 國立嘉義大學 / 水產生物學系研究所 / 94 / The four sulfa agents, sulfadiazine (DIA), sulfamethazine (SMT), sulfamethoxazole (SMX) and sulfadimethoxine (SDM) are sulfonamides. These sulfa agents are widely used in aquaculture practices. The environmental distribution and fate of the four sulfa gents is greatly concerned.
Transformation of the four sulfa agents, DIA, SMT, SMX and SDM, in aquaculture pond waters and sediment slurries were studied. The waters and sediment slurries were collected from a freshwater eel pond and marine shrimp pond. In the first step, a HPLC method for simultaneous determination of DIA, SMT, SMX and SDM in the pond waters and sediment slurries were developed. Second, sorptions of the four sulfa agents in the two sediment slurries were investigated.
Then, effects of light, including natural light and dark conditions, UVA, UVB, UVC and fluorescent lamp on transformation of the four sulfonamides were also elucidated. Finally, observation of photolysis product was also conducted.
An analysis method with HPLC has been established for simultaneous determination of DIA, SMT, SMX and SDM in aquaculture pond waters and sediment slurries. Recoveries of the four sulfa agents from all samples determined at different concentration were 94.01 – 107.32%. The detection limit of DIA, SMT, SMX and SDM were 0.17, 0.22, 0,28 and 0.25 ppm, respectively.
The sorption rates of the four sulfa agents in both types of sediment slurries (10%, wt/vol) were approximately 20% and significantly raised by higher organic matters contents.
The four sulfa agents are unstable when exposed to natural light. Under natural light, SMT was transformed fastest (half-live; t1/2, 0.6 – 2.1 days) among the sulfa agents in both aquaculture pond waters and sediment slurries. Transformation of DIA, SMX and SDM in both aquaculture pond waters were all slower than SMT. The t1/2 were 7.8 – 11.3, 7.5 – 18.4 and 5.2 – 13.3 days in pond waters, and 5.6 – 5.8, 2.1 – 4.4, and 8.8 – 8.9 days in sediment slurries, respectively.
Under darkness, the four sulfa agents were still detectable in both aquaculture pond waters and sediment slurries after 360 days. For example, the residual of SMX in eel pond waters were 0.98% of the initial concentration after 360 days. However, residuals of the other sulfa agents were all over 60%. Under darkness, SMX were undetectable in both aquaculture pond sediment slurries after 90th days. However, no significant transformation of SMT was found in both aquaculture pond sediment slurries after 360 days. The transformation of both DIA and SDM were also quite slow in sediment slurries under darkness.
The four sulfa agents in all waters and sediment slurries were transformed faster exposed to UVA and UVB than UVC or fluorescent lamp. Among the results, SMX in eel pond waters was transformed fastest under UVB, which t1/2 was 8.7 days. DIA in shrimp pond waters was the slowest under UVA, which t1/2 were 392.8 days. In sediment slurries, SMX in eel pond was the fastest under UVB, which t1/2 were 8.8 days. However, SDM in eel pond sediment slurries was the slowest with UVA, which t1/2 was 200.7 days.
An unknown photoproduct peak was observed in DIA solution exposed to UVB. The highest quantum yield in eel and shrimp pond waters was at the 30 and 60th day, respectively.
| Identifer | oai:union.ndltd.org:TW/094NCYU5613005 |
| Date | January 2006 |
| Creators | Tz-Shiun Wang, 王資勛 |
| Contributors | Hong-Thih Lai, 賴弘智 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 117 |
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