Girish Jadhav, D. Salunkhe, D. Nerkar, R. Bhadekar
{"title":"Isolation and characterization of salt-tolerant nitrogen-fixing microorganisms from food","authors":"Girish Jadhav, D. Salunkhe, D. Nerkar, R. Bhadekar","doi":"10.5053/EJOBIOS.2010.4.0.5","DOIUrl":null,"url":null,"abstract":"Halophilic microorganisms are already in use for some biotechnological processes, such as commercial production of s-carotene, polymers (polyhydroxyalkanoates and polysaccharides), enzymes, compatible solutes etc. Considering their commercial importance, food samples (crude salt crystals and raw mango pickle) were used for isolation of halotolerant microorganisms. Two bacterial isolates obtained from food samples were examined for their ability to survive under stressed conditions and their growth response in increasing levels of NaCl (1 to 15% w/v), pH (5.0 to 10.0) and temperature (10 to 70°C). The isolates were rod shaped Gram-positive, salt-tolerant, non-halophilic, nitrogen-fixing strains. Different sugars such as glucose, fructose, maltose, sucrose, xylose and lactose were used to check for acid and gas production. The organisms were studied for their ability to hydrolyse substrates such as casein, starch, gelatin, etc. These organisms (i) grew well in SM basal salt medium and nitrogen-free semi-solid LGI medium (ii) tolerated 10-15% salt concentration (iii) produced acid from D-glucose, D-fructose and sucrose and (iv) utilized glycerol and citrate as carbon source, and v) survived acidic (pH 4-5) and alkaline (pH 9-10) conditions. The results suggested that there is potential to improve their performance as sources of industrially important enzymes. On the basis of morphological attributes and biochemical characteristics the isolates belonged to the genus Bacillus. The results of partial sequencing of 16S rRNA also revealed that the isolates 1 and 2 are closely related to Bacillus subtilis subsp. subtilis NCIB 3610T (97.9% pairwise similarity) and Bacillus sonorensis NRRL B-23154T (99.8% pair-wise similarity) respectively.","PeriodicalId":11848,"journal":{"name":"Eurasian Journal of Biosciences","volume":"4 1","pages":"33-40"},"PeriodicalIF":0.0000,"publicationDate":"2010-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.5053/EJOBIOS.2010.4.0.5","citationCount":"44","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Eurasian Journal of Biosciences","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.5053/EJOBIOS.2010.4.0.5","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"Agricultural and Biological Sciences","Score":null,"Total":0}
引用次数: 44
Abstract
Halophilic microorganisms are already in use for some biotechnological processes, such as commercial production of s-carotene, polymers (polyhydroxyalkanoates and polysaccharides), enzymes, compatible solutes etc. Considering their commercial importance, food samples (crude salt crystals and raw mango pickle) were used for isolation of halotolerant microorganisms. Two bacterial isolates obtained from food samples were examined for their ability to survive under stressed conditions and their growth response in increasing levels of NaCl (1 to 15% w/v), pH (5.0 to 10.0) and temperature (10 to 70°C). The isolates were rod shaped Gram-positive, salt-tolerant, non-halophilic, nitrogen-fixing strains. Different sugars such as glucose, fructose, maltose, sucrose, xylose and lactose were used to check for acid and gas production. The organisms were studied for their ability to hydrolyse substrates such as casein, starch, gelatin, etc. These organisms (i) grew well in SM basal salt medium and nitrogen-free semi-solid LGI medium (ii) tolerated 10-15% salt concentration (iii) produced acid from D-glucose, D-fructose and sucrose and (iv) utilized glycerol and citrate as carbon source, and v) survived acidic (pH 4-5) and alkaline (pH 9-10) conditions. The results suggested that there is potential to improve their performance as sources of industrially important enzymes. On the basis of morphological attributes and biochemical characteristics the isolates belonged to the genus Bacillus. The results of partial sequencing of 16S rRNA also revealed that the isolates 1 and 2 are closely related to Bacillus subtilis subsp. subtilis NCIB 3610T (97.9% pairwise similarity) and Bacillus sonorensis NRRL B-23154T (99.8% pair-wise similarity) respectively.
期刊介绍:
EurAsian Journal of BioSciences (Abbrev. Eurasia J Biosci or EJOBIOS) is an international, refereed electronic journal. It publishes the results of original research in the field of biological sciences restricted tomorphology, physiology, genetics, taxonomy, ecology and biogeography of both prokaryotic and eucaryotic organisms. The journal encourages submission of manuscripts dealing with plant biology, animal biology, plant physiology, microbiology, hydrobiology, ecology and environmental science, ethnobiology, biodiversity and conservation biology. EurAsian Journal of BioSciences publishes original articles in the following areas: -Agriculture, Fisheries & Food -Anatomy & Morphology -Behavioural Sciences -Biology, Biochemistry and Biotechnology -Biophysics -Biology Education -Cellular Biology and Anatomical Sciences -Ecology, Evolution & Environment -Entomology -Forestry -General Biology -Genetics & Heredity -Life Sciences - Other topics -Microbiology and Immunology -Molecular Biology -Mycology -Palaeontology -Parasitology -Pharmacology & Pharmacy -Physiology and Related Sciences -Plant Sciences -Toxicology -Veterinary Sciences -Virology -Zoology