Species Identification of the Genus Aeromonas Isolated from Freshwater Fish Culture-ponds and Seawater in Korea and Their Antibiotic Resistance Patterns

Some species of mesophilic bacteria in the genus Aeromonas were isolated from a snakehead (Channa argus) culture-pond in the Myung-Ji area, a freshwater culture-pond in Pukyung National University, and seawater near the sewage treatment plant in Kwang-An Beach in Pusan. They were identified by biological characteristics, and their susceptibility to ten antibiotics including ampicillin, cefoxitin, ceftazidime cephalothin, cefotiam, chloramphenicol, nalidixic acid, rifampin, cefoperazone-sulbactam, and imipenem, was also studied. Four species in the genus Aeromonas, A. veronii biovar sobria (27 strains), A. caviae (14 strains), A. trota (1 strain), and A. schubertii (1 strain) were identified. A. trota, an unrecorded species in Korea, is reported for the first time in this study. Three strains of A. veronii biovar sobria showed multiple resistance to three kinds of antibiotics and one strain to four drugs. All strains of A. caviae were resistant to more than three drugs and seven strains to four drugs. A. trota was resistant to cephalothin and rifampin, but A. schubertii showed multiple resistance to ampicillin, nalidixic acid, and rifampin.

Biochemical Characteristics of Vibrios isolated from Cultured Shellfish, Ruditapes philippinarum, and Some Species of Wild Shellfish

This study was conducted to investigate the vibrio flora in edible shellfish (Ruditapes philippinarum, Scapharca broughtonii, Batillus cornutus and Mytilus coruscus) which were purchased from seafood-market or collected from shellfish culture bed in Pusan and Masan Bay from May to October 1997. Sixty-three vibrio strains were identified among 438 collected strains. Five species of vibrios [V. alginolyticus (22 strains), V. parahaemolyticus (35 strains), V. costicola (2 strains), L. damsela (V. damsela 2 strains), and V. cholerae non-Ol (2 strains)] were identified by their phenotyfic and biochemical characteristics. Four groups (142 strains) were identified as genus Vibrio by their biological characteristics, but they could not be identified to the species level.

Identification of the Vibrios Isolation from the Shrimp ( Crangon affinis ) in Estuary of Nakdong River in Korea

This study was conducted to investigate the vibrio flora in sand shrimp, Crangon affinis, which were collected in the estuarine area, Dadaepo near Nakdong River in Korea from in June 1996 to in May 1997. Crangon affinis is very important role in food chain in nature because of food for many seabirds and fishes. Six species of vibrios (Vibrio alginolyticus, V. parahaemolyticus, Listonella damsela (V. damsela), V. harveyi, V. splendidus biotype I, V. splendidus biotype II, and V. natriegens, an unrecorded species in Korea) were isolated from the intestine of shrimps and characterized by the biochemical tests.