Ryutaro Ueda

A new selective medium for the isolation of anaerobic bacteria from marine animals

Abstract To develop a selective medium for the isolation of anaerobic gram-positive cocci from marine animals, agar media containing various drugs were examined using strains of Streptococcus sp., Vibrio spp. and Pseudomonas sp. On MAGPC medium, a modified BL agar with 0·3% β-phenylethyl alcohol, the anaerobic Streptococcus sp. grew well whereas other bacterial strains were inhibited. As compared with other four agar media, the MAGPC medium could efficiently isolate anaerobic gram-positive cocci from marine animals.

Effect of transportation on the serum bactericidal activity of Penaeus japonicus and Ovalipes punctatus

Abstract Two crustacean species, the kuruma prawn ( Penaeus japonicus ) and a swimming crab ( Ovalipes punctatus ), were stored in containers (20 l in capacity) containing either seawater or sawdust as packing materials, and transported about 300 km for 8 h by car. The serum bactericidal activity was determined as an indicator of their vigor using a marine bacterium, Vibrio sp. V-9 strain, as the target cell. The serum bactericidal activity of both animals was not significantly influenced when the animals were stored in seawater while the activity decreased markedly in the specimens stored in sawdust. These results strongly suggest that to maintain their ability to resist infection, coastal crustaceans should be transported in seawater with aeration unless there are economic reasons for doing otherwise.

Bactericidal Activities of the Hemolymph of the Japanese Spiny Lobster, Panulirus Japonicus (Decapoda, Palinuridae)

The hemolymph of Japanese spiny lobster was examined for agglutinin and bactericidin activities using 20 (agglutinin) and 25 (bactericidin) strains of marine bacteria. The lobsters sera specifically agglutinated and killed a part of strains belonging to the genera Vibrio and Pseudomonas.

The Intestinal Microflora of the Japanese Spiny Lobster and Other Coastal Animals

The microflora of the intestine and gill of the Japanese spiny lobster was examined. The intestine was predominantly colonized by Vibrio spp., and the gill harbored hibrio spp., Pseudomonas spp., and Flavobacterium spp. In addition, the intestinal microflora of 23 diflerent coastal animal species was compared.

An anaerobic bacterium isolated from Japanese spiny lobster Panulirus japonicus

Abstract Eight strains of bacteria which could not grow under aerobic conditions, were isolated from Japanese spiny lobster. All the strains were Gram-positive, non-sporeforming cocci, and grew well under anaerobic conditions. The strains required a decreased oxygen tension rather than an increased CO 2 tension. Catalase, oxidase, nitrate reductase and urease were not produced. The strains fermented glucose, cellobiose, trehalose and levulose. Indole and H 2 S were not produced. Macromolecule substances including starch, esculin, casein, gelatin and chitin were not hydrolyzed. Lactic acid was the sole product from peptone-yeast extract-Fildes solution-glucose broth. Fermentable carbohydrates were not required. The strains could grow at 20 to 37°C, and required NaCl for growth. From the above results, the strains were identified as anaerobic (aerotolerant) Streptococcus sp.