• YAKHAK HOEJI
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• v.51 no.5
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• pp.343-349
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• 2007

To investigate the effect of ethanol extract of Saxifraga stolonifera MEERBURGH on skin care, we measured anti-oxidant and anti-aging activity. S. stolonifera ethanol extract itself had anti-oxidant activity in a dose-dependent manner in DPPH radical scavenging. Silica dose-dependently increased the intracellular ROS generation in RAW 264.7 cells. S. stolonifera ethanol extract inhibited silica-induced intracellular superoxide anion generation, $H_2O_2$ and hydroperoxide generation in RAW 264.7 cells. S. stolonifera ethanol extract significantly inhibited both hyaluronidase and elastase activity, also significantly inhibited MMP-1(collagenase) activity as well. In NIH 3T3 fibroblast cells, S. stolonifera ethanol extract significantly increased collagen-like polymer synthesis, which suggesting the S. stolonifera ethanol extract might be used as hydration and anti-wrinkle agents. From the above results, it is suggested that the main ingredients of S. stolonifera ethanol extract play an important role in anti-oxidant and anti-aging activity.

• Journal of Nutrition and Health
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• v.15 no.3
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• pp.202-211
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• 1982

A modification of a microbiological assay of vitamin $B_{12}$ was made and used to determine the vita­min levels during kimchi fermentation. A cyanide-buffer solution of pH 6.0 replaced the metabisufite-buffer specified in the A.O.A.C. method. The vitamin $B_{12}$ activity was decreased by blending kimchi samples for 5 minutes and retained the activity by steaming for 10 minutes before blending. The alkali hydrolysis of kimchi at pH 12.0 for 30 minutes at $121^{\circ}C$ was sufficient to destroy the vitamin $B_{12}$ and permit the detection of analogs with the same assay organism. Vitamin $B_{12}$ reached a maximum of 47ng/100g during the fermentation of kimchi ${15}\;4^{\circ}C.$ Inoculation of the kimchi with Propionibacterium shermanii (ATCC 13673) increased the vitamin production to a maximum of 102ng/100g at 1 week of fermentation. Soy flour (0.5%) or beef extract (0.05%), which were regarded as protein sources, added to the inoculated kimchi further increased the vitamin $B_{12}$ activity to 197 and 203ng/100g.

• The Microorganisms and Industry
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• v.31 no.1
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• pp.4-14
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• 2005

• Korean Journal of Microbiology
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• v.26 no.3
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• pp.270-277
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• 1988

Microorganisms isolated from soil (150 strains), fungi (39 strains), yeasts (9 strains) and Streptomyces species (39 strains) were assayed for L-phenylalanine ammonia-lyase(PAL) activity. 17 strains of fungi and 46 strains of soil isolates were proved to produce PAL, Aspergillus panamensis, Penicillium varioti and 11 soil isolates showed comparatively large PAL activity. When PAL activity was assayed with cell-free extracts of these 13 strains and 7 strains of Rhodotorula and Rhodosporidium geni, Rhodosporidium toruloides (IFO 0559) showed the highest PAL activity with 0.333 units per g of the wet cell weight.

• Korean Journal of Microbiology
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• v.14 no.1
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• pp.36-38
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• 1976

The insecticides, Dithane-M45 and copper sulfate, were introduced in this experiments to elucidate their effects on the nodulation of soybean plant(Glycine max Meer) by Rhizobium japonicum. The nodulation activity was inhibited in accordance with increase of their concentration.

• Preventive Nutrition and Food Science
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• v.9 no.2
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• pp.121-125
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• 2004

Effects of chemical treatment with a citric acid solution or ozonated water on microbiological changes in lettuce and cabbage during storage were studied. Fresh lettuce and cabbage samples were cut into small pieces and treated by soaking in either ozonated water or a citric acid solution. After treatment, populations of total bacteria, yeast and mold, and E. coli were determined. Numbers of microorganisms increased during storage, but ozonated water and citric acid treatments retarded the increase in microbial growth. Among treatments, 1 % citric acid treatment was the most effective in terms of microbiological change and inhibition of polyphenoloxidase (PPO). For lettuce, citric acid treatment decreased the microbial growth overall by 1.5 log CFU/g and inhibited the PPO activity by 80%. These results indicate that chemical-treated lettuce and cabbage retained a better quality than those of the control during storage.

• Journal of Microbiology and Biotechnology
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• v.6 no.1
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• pp.19-25
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• 1996

Chitosanase from Bacillus sp. HW-002 was purified with CM-cellulose column chromatography, and HPLC with DEAE- TSK gel and YMC-pack Diol 120. The purified enzyme appeared as a single band on SDS-polyacrylamide gel. The molecular weight of the enzyme was estimated to be about 46 kDa on SDS-polyacrylamide gel, and was estimated to be about 23 kDa by GFC. The optimal pH of chitosanolytic activity was about pH 5.5-6.0, and the purified enzyme was most stable at pH 5.0. The optimal temperature of chitosanolytic activity was $65^{\circ}C$ and the enzyme was stable at $45^{\circ}C$ for 1 h. Chitosan was the most favorable substrate among various $\beta$-glucan. UVmax of the purified enzyme was 195 nmand was not noted around 280 nm. The main product of enzyme reaction with chitosan was chitobiose.

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.203.1-203
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• 2005

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.215.4-215
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• 2005

• Proceedings of the Microbiological Society of Korea Conference
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• 2003.05a
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• pp.122-124
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• 2003

Cyclodextrin glucanotransferase (CGTase) and endoxylanase genes of Bacillus sp. were subcloned down-stream of yeast ADH1 promoter and expressed in S. cerevisiae. Most of the CGTase and endoxylanase expressed were detected in the extracellular medium with activity of 0.6 and 7-8 unit/ml, respectively. The recombinant enzymes were secreted as N-linked-glycosylated forms, resulting an enhanced thermal stability. CGTase predominantly produced $\alpha-cyclodextrin$ from starch and endoxylanase produced xylobiose and xylotriose from xylan.