유독성 플랑크톤 Alexandrium catanella에 대한 Arthrobacter sp. AB-1의 살조효과

Abstract

The distributions and algicidal effects produced by marine bacteria were investigated and showed the inhibition of the growth of the red tide microalgae, Alexandrium catanella. On the basis of the results on the biochemical analysis and 16S rRNA gene sequencing, the algicidal bacterium was identified as Arthrobacter sp. AB-1. A total of 100 strains were isolated from the seawater samples filtered with the meed(pore size, 0.2-㎛). These strains were prown F/2-Si medium which contained A. catanella. Arthrobacter sp. AB-1 were isolated with the algicidal effects against A. catanella. A. catanella(2.0×103 cells/㎖) was decreased to less than 8.0×102 cells/㎖ within 6hours after inoculation of Arthrobacter sp. AB-1. In addition, the killing effects of Arthrobacter sp. AB-1 were increased in accordance with the number of bacterial cell inoculated in a dose dependent manner. Especially, the filtrate of bacteria culture with pore size of 0.2-㎛ revealed a dramatic effect, showing that A. catanella was decreased to less than 4.0×102 cells/㎖ the addition of within 6hrs, 9hrs, 12hrs after inoculations of the culture filtrate with concentration 1%, 5%, 10%, respectively. This result indicated that a substance showing algicidal activity were released by Arthrobacter sp. AB-1. After treatment of culture filtrate, we have with heat 4℃, 10℃, 20℃, 30℃, 40℃, 50℃, 70℃, 100℃ for 1hr. Obtained that the same effects against A. catanella, suggesting that the algicidal matters is stable for heat treatment.