• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1237-1245
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• 1997

Interspecific fusants were made from the cells of two strains of Lactobacillus genus, a streptomycin resistant Lactobacillus sp. JC-7 and a kanamycin resistant L. acidophilus 88. The morphological and physiological properties of the fusants were examined by determining bacteriocin productivity, acid-producing activity, ability of carbohydrates utilization and three important enzyme activities. The fusants produced a bacteriocin against indicator strains and fusant No. 1, 4 exhibited a larger inhibition zone compared to that of L. acidophilus 88. $\beta$-Galactosidase, phospho-$\beta$-galactosidase, lipase activities and resistance to NaCl of Lactobacillus sp. JC-7 were better than those of L. acidophilus 88. Fusant No. 3 and 7 exhibited excellent lipase activities. Protease activity and acid productivity of L. acidophilus 88 were better than those of Lactobacillus sp. JC-7. Proteasse activities of all fusants were higher than those of parental strains, and expecially fusant No. 5 and 7 exhibited excellent proteolysis ability.

• Microbiology and Biotechnology Letters
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• v.25 no.2
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• pp.121-128
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• 1997

A lactic acid bacterium was isolated from kimchi. The isolated strain was identified as the genus Lactobacillus through its morphological, cultural, and physiological characteristics and named as Lactobacillus sp. JC-7. The optimum conditions for the electrofusion between streptomycin (2.5 mg/ml) resistant mutant of Lactobacillus acidophilus 88 and kanamycin (600 $\mu$g/ml) resistant mutant of Lactobacillus sp. JC-7 were evaluated. The highest number of fusants were obtained at a capacitance value of 120 msec (1670 $\mu$F), a field strength of 100 V/cm, and a pulse controller setting of 72$\Omega$. The optimum pH of electroporation buffer was 7.5 and the concentration of divalent cation was 1 mM Mg$^{2+}. Electrofusants were efficiently obtained by addition 20% polyethylene glycol to elec- troporation buffer. The yield of fusion was better than that of using polyethylene glycol mediated chemical induction.