Microbial Dynamics and Nutritional Status of Namsing: A Traditional Fermented Fish Product of Mishing Community of Assam

  • Naimisha Chowdhury
  • Gunajit Goswami
  • Smita Hazarika
  • Sushanta Sharma Pathak
  • Madhumita BarooahEmail author
Research Article


The present study reports on the microbial dynamics and the accompanied nutritional changes during the fermentation process of Namsing. Fermentation of fish during Namsing preparation revealed a significant increase in mineral content with the passage of fermentation time. Changes in microbial dynamics such as mesophilic bacteria, lactic acid bacteria (LAB) and Enterobacteriaceae were monitored during the indigenous fermentation process. The mesophilic bacterial count of Namsing was 3.44 log CFU/g on the first day which increased to 8.2 log CFU/g on the 7th day and decreased gradually to 3.36 log CFU/g on the 28th day of fermentation. Yeasts and moulds were not detected during the fermentation period. Lactic acid bacteria were not detected until the 21st day. However on the 28th day, the lactic acid bacteria were recorded in the range of 1–2 log CFU/g. Coliform or other gram-negative bacteria were detected in the range of 2–2.8 log CFU/g till the end of fermentation. A total of 27 isolates were selected for further study based on their colony morphology and identified through biochemical and molecular analysis. The isolates belonged to the genus Bacillus (40.7%), Lactobacillus (7.4%), Kurthia (14.8%), Providencia (11%), Wohlfahrtiimonas (7.4%), Paenibacillus (3%), Staphylococcus (3%) Klebsiella (7.4%) and Vagococcus (3%). Among the 27 isolates, 11 isolates were further screened quantitatively for protease activity and using casein as substrate. The highest protease activity (15.60 ± 0.31 units/mL) was shown by the isolate Kurthia gibsonii (N11).


Namsing Fermented fish Protease activity Microbial dynamics Mineral contents 



The authors are grateful to the Department of Agricultural Biotechnology and DBT-AAU center, Assam Agricultural University (AAU) for providing the necessary facilities to carry out the present work.

Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflict of interest to publish this manuscript.


  1. 1.
    Sathe GB, Mandal S (2016) Fermented products of India and its implication: a review. Asian J Dairy Food Res 35:1–9. CrossRefGoogle Scholar
  2. 2.
    Tamang JP, Tamang N, Thapa S et al (2012) Microorganisms and Nutritional value of Ethnic fermented foods and alcoholic beverages of North East India. Indian J Tradit Knowl 11:7–25Google Scholar
  3. 3.
    Goswami G, Deka P, Das P et al (2017) Diversity and functional properties of acid-tolerant bacteria isolated from tea plantation soil of Assam. 3 Biotech. CrossRefPubMedPubMedCentralGoogle Scholar
  4. 4.
    Thapa N (2016) Ethnic fermented and preserved fish products of India and Nepal. J Ethn Foods 3:69–77. CrossRefGoogle Scholar
  5. 5.
    Tamang JP (2015) Naturally fermented ethnic soybean foods of India. J Ethn Foods 2:8–17. CrossRefGoogle Scholar
  6. 6.
    Majumdar RK, Roy D, Bejjanki S, Bhaskar N (2016) An overview of some ethnic fermented fish products of the Eastern Himalayan region of India. J Ethn Foods 3:276–283. CrossRefGoogle Scholar
  7. 7.
    AOAC (1999) Official methods of analysis, 16th edn. The Association of Official Analytical Chemists, GaithersburgGoogle Scholar
  8. 8.
    AOAC (2000) Official methods of analysis, 17th edn. The Association of Official Analytical Chemists, Maryland, USAGoogle Scholar
  9. 9.
    AOAC (1984) Official methods of analysis, 14th edn. The Association of Official Analytical Chemists, Washington DCGoogle Scholar
  10. 10.
    Tamura K, Stecher G, Peterson D et al (2013) MEGA6: molecular Evolutionary Genetics Analysis Version 6.0. Mol Biol Evol 30:2725–2729. CrossRefPubMedPubMedCentralGoogle Scholar
  11. 11.
    Cupp-Enyard C (2008) Sigma’s non-specific protease activity assay—casein as a substrate. J Vis Exp. CrossRefPubMedPubMedCentralGoogle Scholar
  12. 12.
    Beaumont M (2002) Flavouring composition prepared by fermentation with Bacillus spp. Int J Food Microbiol 75:189–196CrossRefPubMedGoogle Scholar
  13. 13.
    Richard MJ, Roussel AM (1999) Micronutrients and ageing: intakes and requirements. Proc Nutr Soc 58:573–578CrossRefPubMedGoogle Scholar
  14. 14.
    Yirankinyuki FF, Lamayi DW, Sadiq BA, Yakubu MU (2013) Proximate and some minerals analysis of Colocasia Esculenta (TARO) leaves. J Med Biol Sci 3:8–14Google Scholar
  15. 15.
    Goswami G, Baruah H, Boro RC, Barooah M (2016) Fermentation reduces anti-nutritional content and increases mineral availability in Poita bhat. Asian J Chem 28:1929–1932. CrossRefGoogle Scholar
  16. 16.
    Mohite BV, Chaudhari GA, Ingale HS, Mahajan VN (2013) Effect of fermentation and processing on in vitro mineral estimation of selected fermented foods. Int Food Res J 20:1373–1377Google Scholar
  17. 17.
    Nazmanara Khanum M, Takamura H, Matoba T (1999) Nutritional composition of a semi-fermented fish product (Chapa Shutki) in Bangladesh. J Home Econ Jpn 50:703–712Google Scholar
  18. 18.
    Osman OA, Sulieman AME, Elkhalifa EA, Mustafa WA (2012) Chemical and microbiological characteristics of fermented fish product, Fassiekh. Food Pub Heal 2:213–218. CrossRefGoogle Scholar
  19. 19.
    Thapa N, Pal J, Tamang JP (2006) Phenotypic identification and technological properties of lactic acid bacteria isolated from traditionally processed fish products of the Eastern Himalayas. Int J Food Microbiol 107:33–38. CrossRefPubMedGoogle Scholar
  20. 20.
    Whitman WB, Parte AC (2009) The firmicutes, 2nd edn. Springer, New YorkGoogle Scholar
  21. 21.
    Garrity GM (2005) Bergey’s manual of systematic bacteriology. The proteobacteria. Springer, BerlinGoogle Scholar
  22. 22.
    Borsodi AK, Kiss RI, Cech G et al (2010) Diversity and activity of cultivable aerobic planktonic bacteria of a saline Lake located in Sovata, Romania. Folia Microbiol (Praha) 55:461–466. CrossRefGoogle Scholar
  23. 23.
    Garrity GM, Holt JG (2001) The road map to the manual. Bergey’s manual® systematic bacteriology. Springer, New York, pp 119–166CrossRefGoogle Scholar
  24. 24.
    Ahmed S, Dora KC, Sarkar S et al (2013) Quality analysis of shidal—A traditional fermented fish product of Assam, North-East India. Indian J Fish 60:117–123Google Scholar
  25. 25.
    Stackebrandt E, Frederiksen W, Garrity GM et al (2002) Report of the ad hoc committee for the re-evaluation of the species definition in bacteriology. Int J Syst Evol Microbiol 52:1043–1047. CrossRefPubMedGoogle Scholar
  26. 26.
    Mi-na U, Lee C-H (1996) Isolation and identification of Staphylococcuss sp. from Korean fermented fish products. Microbiol Biotechnol 6:340–346Google Scholar
  27. 27.
    Schmidtke LM, Carson J (1994) Chararacteristics of Vagococcus salmoninarum isolated from diseased salmonid fish. J Appl Bacteriol 77:229–236. CrossRefPubMedGoogle Scholar
  28. 28.
    Shewmaker PL, Steigerwalt AG, Morey RE et al (2004) Vagococcus carniphilus sp. nov., isolated from ground beef. Int J Syst Evol Microbiol 54:1505–1510. CrossRefPubMedGoogle Scholar
  29. 29.
    Pereira Rodarte M, Dias, Vilela DM, Schwan RF (2011) Proteolytic activities of bacteria, yeasts and filamentous fungi isolated from coffee fruit (Coffea arabica L.). Acta Sci Agron Mar 33:457–464. CrossRefGoogle Scholar
  30. 30.
    Chantawannakul P, Oncharoen A, Klanbut K et al (2002) Characterization of proteases of Bacillus subtilis strain 38 isolated from traditionally fermented soybean in Northern Thailand. Sci Asia 28:241–245CrossRefGoogle Scholar

Copyright information

© The National Academy of Sciences, India 2018

Authors and Affiliations

  • Naimisha Chowdhury
    • 1
  • Gunajit Goswami
    • 1
  • Smita Hazarika
    • 1
  • Sushanta Sharma Pathak
    • 2
  • Madhumita Barooah
    • 1
    Email author
  1. 1.Department of Agricultural BiotechnologyAssam Agricultural UniversityJorhat-13India
  2. 2.Biswanath College of AgricultureAssam Agricultural UniversityBiswanath CharialiIndia

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