Degradation of Cochlodinium polykrikoides using photocatalytic reactor with TiO2-coated alumina

Cochlodinium polykrikoides (C. polykrikoides) is one of the most harmful red tide dinoflagellates due to its great economic damage and compromising recreational opportunity and public health. Titanium dioxide (TiO₂) is known to be used as a photocatalyst for the control of the aquatic invasive algae under natural and artificial light. The purpose of this study was to design a highly efficient continuous photocatalytic reactor with TiO₂-coated alumina for the demonstrated efficient degradation of C. polykrikoides. TiO₂ photocatalyst beads were prepared by sol-gel dip-coating method using titanium tetra iso-propoxide on alumina. After 40 min of ultraviolet illumination time, the reduction of C. polykrikoides cell number was more than 80%. The degree of degradation of C. polykrikoides increased in a time-dependent manner in this novel reactor. The degradation begins with photocatalytic action by the oxidative species of TiO₂ on the protective cell structures of C. polykrikoides.     

Infection status of the sea eel (Astroconger myriaster) purchased from the Noryangjin fish market with anisakid larvae]

Although the sea eel (Astroconger myriaster) is suspected as one of the most important fish host for human anisakiasis in Korea, no report has been made on the infection status of the sea eel with anisakid larvae. In the present study, 26 sea eels (Astroconger myriaster) were purchased from the Noryangjin fish market in Seoul, and anisakid larvae were collected from their viscera, muscle, head and skin. The collected larvae were classified by their morphological types. A total of 1,351 anisakid larvae were collected from 15 of 26 fish examined. Among them, 1,269 were recovered from the viscera, 66 from the muscle, and 16 from the head and skin. Morphologically, most of the anisakids were classified into 6 known larval types, Anisakis type I (564 larvae) of Berland (1961), Contracaecum type A (409) and type D (5) of Koyama et al. (1969), Contracaecum type C' (83) and type D' (117) of Chai et al. (1986), and Contracaecum type V (1) of Yamaguti (1935). Remaining 172 specimens were new in the available literature, hence, designated as Contracaecum type A' (new type). The present results revealed that the sea eels caught in the Korean waters are heavily infected with anisakid larvae, not only in their viscera but also in the muscle, and Anisakis type I was the most common among the 7 larval types.