Bacterial communities in fish sauce mash using culture-dependent and -independent methods

• Published in: Journal of general and applied microbiology Vol. 58; no. 4; pp. 273 - 281
• Main Authors: Fukui, Youhei, Yoshida, Mitsuhiro, Shozen, Kei-ichi, Funatsu, Yasuhiro, Takano, Takashi, Oikawa, Hiroshi, Yano, Yutaka, Satomi, Masataka
• Format: Journal Article
• Language: English
• Published: Tokyo Applied Microbiology, Molecular and Cellular Biosciences Research Foundation 01.01.2012; Microbiology Research Foundation
• Subjects: Animals; Bacillus subtilis; Bacteria - classification; Bacteria - genetics; Bacteria - growth & development; Bacteria - isolation & purification; bacterial community; Bacterial Load; Biological and medical sciences; Biota; clone library; culture-dependent method; DNA, Bacterial - chemistry; DNA, Bacterial - genetics; DNA, Ribosomal - chemistry; DNA, Ribosomal - genetics; Fermentation; fish sauce; Fishes - microbiology; Food Microbiology; Fundamental and applied biological sciences. Psychology; Hydrogen-Ion Concentration; Lactic Acid - analysis; Microbial Viability; Microbiology; Molecular Sequence Data; RNA, Ribosomal, 16S - genetics; Sequence Analysis, DNA; Staphylococcus spp; Tetragenococcus halophilus; Time Factors; Tetragenococcus; Staphylococcus spp; culture-dependent method; Method; Staphylococcus; Fish sauce; Micrococcales; Bacteria; Micrococcaceae; bacterial community; clone library; Microbial community; Culture; Tetragenococcus halophilus; Clone
• ISSN: 0022-1260; 1349-8037
• DOI: 10.2323/jgam.58.273

In fish sauce production, microorganisms are associated with the fermentation process; however, the sequential changes in the bacterial communities have never been examined throughout the period of fermentation. In this study, we determined the bacterial floras in a fish sauce mash over 8 months, using three different culture media and 16S rRNA gene clone library analysis. During the first 4 weeks, viable counts of non-halophilic and halophilic bacteria decreased and were dominated by Staphylococcus species. Between 4 and 6 weeks, halophilic and highly halophilic bacterial counts markedly increased from 107 to 108 cfu/g, and the predominant species changed to Tetragenococcus halophilus. The occurrence of T. halophilus was associated with an increase of lactic acid and a reduction of pH values. In contrast, non-halophilic bacterial counts decreased to 106 cfu/g by 6 weeks with Bacillus subtilis as the dominant isolate. Clone library analysis revealed that the dominant bacterial group also changed from Staphylococcus spp. to T. halophilus, and the changes were consistent with those of the floras of halophilic and highly halophilic isolates. This is the first report describing a combination approach of culture and clone library methods for the analysis of bacterial communities in fish sauce mash.