• Microbiology and Biotechnology Letters
• /
• v.26 no.3
• /
• pp.269-274
• /
• 1998

Decolorizing characteristics of crystal violet by Enterobacter cloace MG82, which can decolorize rapidly triphenylmethane dyes, were investigated. The higher growth and decolorization activity was shown at big ratio of dissolved oxygen in the medium. The decolorization activity of crystal violet revealed highest at the middle of lag phase. As the concentration of crystal violet was higher, the growth of E. cloacae MG82 and decolorizing activity of crystal violet by this strain were worse. The maximum concentration of crystal violet at which E. cloacae MG82 be able to grow was 375 ${\mu}$M. E. cloacae MG82 was not able to use the crystal violet itself as a sole carbon source. So, it was shown that growth of E. cloacae MG82 and decolorization activity of crystal violet by this strain needed addition of another energy sources except this dye.

• Journal of Food Hygiene and Safety
• /
• v.16 no.2
• /
• pp.89-95
• /
• 2001

This study was conducted to find material having antibacterial activity. The effects of preservatives, antibiotics and oriental medicines on growth of teated microorganisms were investigated. The growth of all tested bacteria was inhibited by water extract of Schizandra chinensis. Antibacterial activity on the concentration of Schizandra chinensis extract was tested. The growth of Escherichia coli W3110, Enterobacter colacae MG82 and Salmonella typhimurium was extraordinarily inhibited by more than 0.2% concentration of Schizandra chinensis extract. The specific growth rate of Escherichia coli W3110, Enterobacter cloacae ME82 and Salmonella typhimurium under control conditin had mean values of 0.514(hr￣), 0.381(hr￣) and 0.489(hr￣), respectively. When 0.2% of Schizandra chinensis extract was added, specific growth rates of Escherichia coli W3110, Enterobacter colacae MG82 and Salmonella typhimurium wre decreased, compared to contorl, in 1.26, 2.23 and 1.50 fold, respectivley. Minimal inhibiotory concentration of Schizandra chinensis extract was 0.25% on the tested microorganisms The growth of Enterobacter cloacae MG82 was more inhibited by Schizandra chinensis extract than other tested microorganisms.

• Microbiology and Biotechnology Letters
• /
• v.25 no.1
• /
• pp.37-43
• /
• 1997

Triphenylmethane was decolorized rapidly by enterbacter cloacae MG 82 at initial reaction time. The spheroplast showed higher activity of triphenylmentane decolorization than that of intact cell suspension. The outer part of the bacterial cell envelope and the peptidoglycan are important for the function of transport barrier of triphenylmethane. In intact cell, decolorization activity was higher at 37$\circ $C than at $\circ $C, indicating that triphenylmethane decolorization is due to the enzyme reaction. Culture filtrate showed no decolorization activity, while cell-free extract appeared high activity of 1.45 units, clearly showing that decolorization activity was due to the cell-free extract. Comparing decolorization activities of cell fractions, it was found that decolorization activity was located at the compartment of cytoplasmic membrane. The enzyme activity was also shown to be Mg$^{++}$-dependent. The optimum pH and temperature of enzyme activity were 7.0 and 50$\circ $C, respectively. The thermostability of this enzyme at 35$\circ $C was kept to 58% for 3 hours.

• YAKHAK HOEJI
• /
• v.38 no.2
• /
• pp.140-148
• /
• 1994

${\beta}-Lactamase$ stability, chemotherapeutic activity, and pharmacokinetics of 7-[(Z)-2-(2-aminothiazole-4-yl)-2-methoxyiminoacetamido]-3-[4-(2-pyridyl)piperazinyl]thiocarbonylthiomethyl-3-cephem-4-carboxylic acid(CEN1), 7-[(Z)-2-(2-aminothiazole-4-yl)-2-methoxyiminoacetamido]-3-[4-(2-pyrimidyl)piperazinyl]thiocarbonylthiomethyl-3-cephem-4-carboxylic acid(CEN2), pivaloyloxymethyl-7-[(Z)-2-(2-aminothizaole-4-yl)-2-methoxyiminoacetamido]-3-[4-(2-pyridyl)piperazinyl]thiocarbonyl-thiomethyl-3-cephem-4-carboxylate(CEN1P), and pivaloyloxymethyl-7-{(Z)--2-(2-aminothizaole-4-yl)-2-methoxyiminoacetamido]-3-[4-(2-pyridyl)piperazinyl]thiocarbonyl-thiomethyl-3-cephem-4-carboxylate(CEN2P) were examined. CEN1, CEN2, CEN1P, and CEN2P were very stable to the ${\beta}-lactamase$ obtained from three strains(Enterobacter cloacae P99, Escherichia coli TEM, and Citrobacter freundii). Chemotherapeutic activities$(ED_{50})$ of CEN2 and CEN2P against experimental systemic infections due to Streptococcus pyogenes 77A and Escherichia coli 078 were superior to those of CEN1 and CEN1P, respectively. The $ED_{50}$ values of CEN1, CEN2 were 5.82 mg/kg, 0.89 mg/kg(s.c., S. pyogenes 77A) while those of CEN1P, CEN2P were 14.56mg/kg, 6.40mg/kg(p.o., S. pyogenes 77A), respectively. The pharmacokinetics of CEN1, CEN2, CEN1P, and CEN2P were investigated in mice and rats. In mice, peak blood levels of $1.25\;{\mu}g/ml$ were recorded within 20 min after oral administration of a single dose equivalent to 40 mg/kg CEN1P. Cmax of CEN1P was much higher than that of CEN1 in mice and rats. Oral absorption of CEN2P was much higher than that of CEN2.