Isolation of Halophilic and Halotolerant Microorganisms from the Bakhtegan Lake and the Effect of Physicochemical Factors on Their Frequency

Document Type : Technical Note

Authors

1 Assistant Prof., Azad Islamic University, Jahrom Branch

2 Former Grad. Student of Microbiology. Azad Islamic University, Jahrom Branch

Abstract

 The lake in the protected Bakhtegan zone is the shelter to wildlife and very important from an ecological and environmental viewpoint. The lake has a unique diversity in terms of Halophilic and Halotolerant bacteria. Based on our experiments, from among the six genera of Halobacteriaceae, only the four Halobacterium, Haloarcula, Halococcus, and Haloferax genera were isolated, the greatest frequency (mean: 54%) belonging to Halobacterium and the least frequency (mean: 4%) belonging to Haloferax among the isolated genera. The Halotolerant bacteria isolated included Pseudomonas sp., Flavobacterium sp., Micrococcus sp. and Bacillus sp. genera. The greatest number of Halotolerant bacteria isolated from the lake water was Pseudomonas (mean: 72%). Furthermore, the number of total coliforms was greater than the number of fecal coliforms. Statistical analysis revealed that Halophilic and Halotolerant colonies had the same mean numbers only at Tashk and Gomban sampling sites but that the mean numbers obtained at Dehzir sampling site was significantly different from those obtained at the former two. It was also found that increasing salt concentration and pH level increased the number of halophilic colonies while increased levels of dissolved oxygen decreased their numbers. Salt concentration, pH level, and DO level had similar effects on the number of total and fecal coliform colonies. 

Keywords

References

 1- کاشف، م. ح.، (1372). تالاب های ایران. اداره کل حفاظت محیط زیست استان فارس.
2- Kunte, H. (1995). “Halophilic microorganisms.” Can. J. Microbiol., 48, 185-197.
3- Madigan, M., and Oren, A. (1999). “Thermophilic and halophilic extremophils.” Curr. Opin. Micro., 2, 265-269.
4- Golinski, E. A. (1995). “Osmoadaptation in bacteria.” Adv. Micro. Physiol., 37, 273-284.
5- Reed, R. (1993). “Microbs in extreme environment.” Can. J. Microbiol., 43, 588-599.
6- Manual of oceanographic observation and pollutant analysis methods (MOOPAM). (1999). ROPME.,Kuwait.
7- Holt, J., and Krieg, N. (1994). Bergey`s manual of determinative bacteriology, 9th Ed., Williams and Wilkins, ASM-Washington, D.C.
8- Gorshkova, N. (2003). “Marinobacter excellens sp.nov., isolation from sediments of the sea of Japan.” Int. J. Syst. Evol. Microbiol., 53 , 2073-2078.
9- Greenbery, A.(1992). Standard methods for examination of water and wastewater, 18th Ed., American Public Health Association.
10- Forsyth, M. P., and Shindler, D. B. (1971). “Salt tolerance of intertidal marine bacteria.” Can. J. Microbiol., 17, 825-828.
11- Galinski, E. A., and Truper, H. G. (1994). Microbial behaviour in salt –stressed ecosystems.” FEMS Microbiol. Rev, 15, 95-108.
12- Brisou, J., Courtois, D., and Denis, F. (1997). “Microbiological study of a hyper saline lake in French Somali land.” Appl. Microbiol., 27, 819-822.
Journal of Water and Wastewater; Ab va Fazilab ( in persian )
Volume 18, Issue 3 - Serial Number 3
Serial number:63
September 2007
Pages 81-87

Files

Share

How to cite

Statistics