Isolation and identification of bacteria from marine market fish Scomberomorus guttatus (Bloch and Schneider, 1801) from Madurai district, Tamil Nadu, India
Abstract The present study was conducted to evaluate the hygienic quality and freshness of fish Indo-pacific King Mackerel “Scomberomorus guttatus” through the investigation of the occurrence of bacteria which is an indicator for fish quality. Fishes were collected every fortnight from Madurai fish market on monthly twice of January 2014 to March 2014. Skin surface of the fish was examined. Escherichia coli, Proteus vulgaris, Bacillus subtilis, Klebsiella pneumonia, Pseudomonas aeruginosa and Staphylococcus aureus were identified by Biochemical tests (IMViC Tests). Among the six bacterial species E. coli and K. pneumonia were found in all the collected samples where as other bacterial species were not found. The result of this study revealed that raw fish sold in Madurai fish market has high contamination so the presence of the bacterial species has strongly suggested the urgent need to improve the quality control systems in Madurai fish market.
Bioactive potential of actinobacteria isolated from the gut of marine fishes
The study was undertaken to explore the gut-associated actinobacteria from two marine fish with special reference to antimicrobial and anti-quorum sensing activity. A total of 40 actinobacterial strains were isolated from fish gut samples using starch casein agar and Kuster’s agar medium. About 14 morphologically different strains recovered from Rastrelliger kanagurta (Indian mackerel) and Panna microdon (Panna croaker) were screened for the antimicrobial activity against Staphylococcus aureus MTCC96, Escherichia coli MTCC739, Salmonella enterica, Candida albicans, and quorum sensing inhibition (QSI) against Chromobacterium violaceum and Serratia marcescens. The actinobacterial strain IM20 from R. kanagurta showed both antimicrobial and QSI activity, whereas the strains PCA1 and PCA4 from P. microdon showed only antimicrobial activity. Strain IM20, which showed wide range of activity, was selected as the potential strain for further studies. Thus, the findings suggested that the fish-associated actinobacteria is a promising source for antimicrobial compounds for developing novel therapeutic drugs.
Die Populationsdynamik Von Canthocampt Us Staphylinus (Jurine) (Copepoda, Harpacticoida) Im Litoral Des Bodensees
The population dynamics of Canthocamptus staphylinus in the littoral zone of Lake Constance are described (fig. 2). Adult animals aestivate as cysts. The main part of the population emerges from the cysts in autumn. During the resting stage and the first spell after emerging, mortality is very low (fig. 3). Reproduction, expressed as numbers of ovigerous females, begins in November and reaches its maximum in January. The new generation becomes adult in May/June and encysts without previous reproduction. According to Sarvala (1979) it may be possible, that in littoral populations dormancy is induced by long day periods and temperatures of over 12° C (figs. 1, 2). In the profundal zone C. staphylinus also forms cysts, however, both light and temperature are not likely to induce this stage in depths of over 60 m.