• 한국수산과학회지
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• 제42권6호
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• pp.569-573
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• 2009

The biochemical and microbiological changes of the hard clam shikhae were studied during fermentation at $4-18^{\circ}C$ for 45 days. For preparation of the shikhae, the shucked hard clams were blanched into 2% saline solution and were soaked in seasoning solution before mixing with salt, cooked grain and spices. During fermentation, the initial pH steadily decreased from 5.0 to 4.6, but $NH_2-N$ and VBN concentrations increased to 127 mg/100 g and 27.0 mg/100 g, respectively. Alanine, taurine, glutamic acid, and aspartic acid concentrations increased, but arginine concentration decreased by fermentation. The major organic acids of the fermented shikhae were lactic acid, succinic acid and acetic acid. The major free sugar were maltose, glucose and fructose. The concentration of total viable cell ($2.1\times10^5$ CFU/g) and proteolytic bacteria ($1.2\times10^5$ CFU/g) increased to $4.4\times10^8$ CFU/g and $9.8\times10^7$ CFU/g, respectively until day 15 and then slightly decreased. The concentration of yeast ($2.4\times10^3$ CFU/g) increased to $1.6\times10^7$ CFU/g until day 25, but lactic acid bacteria ($5.0\times10^8$ CFU/g) increased to $5.0\times10^8$ CFU/g until day 9. Vibrio species was not detected on the TCBS agar during fermentation.

• 한국수산과학회지
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• 제44권6호
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• pp.605-611
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• 2011

This study examined the suitability of characteristics of potential strains of probiotic bacteria. Among 25 lactic acid bacteria isolated from Korean traditional fermented food, the Hard Clam Meretrix meretrix Shikhae, the SH-10 strain, which exhibited superior resistance to low pH and bile salts, was selected as a potential probiotic bacteria. By examining carbohydrate utilization, morphological properties, and the 16S rRNA gene sequence, the SH-10 strain was identified as Pediococcus pentosaceus (hereafter, P. pentosaceus SH-10). P. pentosaceus SH-10 was resistant to amikacin, cefotetan, ciprofloxacin, gentamicin, kanamycin, nalidixic acid, streptomycin, and vancomycin. Tests of antimicrobial activities against pathogens such as Bacillus cereus, Listeria monocytogenes, Salmonella choleraesuis, and Staphylococcus aureus, indicated that P. pentosaceus SH-10 inhibited the growth of pathogenic bacteria. These results suggest that P. pentosaceus SH-10 can be developed as a probiotic bacteria.