• Journal of Environmental Health Sciences
• /
• v.31 no.5 s.86
• /
• pp.444-450
• /
• 2005

The present study was designed to investigate whether traditional Korean fermented soybean paste(doen-jang) and soybean extracts have inhibitory effects on the growth of KB cell, an oral epithelioid cancer cell. When KB cell ATCC CCL-17 was cultivated for 48 flours with the addition of 0.5% of the five types or doen-jang extract, the growth of KB cell was inhibited by all types of extract, and ethyl acetate extract showed the highest inhibitory effect. In case of soybean extract, all types of extract also showed KB cell inhibitory effects, however, generally less than those of doen-jang extract. When ethyl acetate extract of doen-jang was added in different concentrations and KB cell was cultivated for 24 hours and 45 hours, strong inhibitory effect began to appear from the concentration of 1.25 mg/ml. Although soybean extract showed such a tendency, its effect was lower than that of doen-jang extract. These results indicate that doen-jang extract has inhibitory effect against KB cell, and particularly ethyl acetate extract has the highest effect. The effect of doen-jang extract might be possibly enhanced by the fermentation of soybeans. It is assumed that doen-jang extract may be used to develop nontoxic medicines for preventing and treating oral diseases.

• Journal of Environmental Health Sciences
• /
• v.34 no.3
• /
• pp.207-212
• /
• 2008

This study was performed to investigate the anti-microbial activity of extract from Korean fermented soybean paste (doen-jang) against 16 types of oral microbes, and to determine the minimum inhibition concentration (MIC) of the extract for three major microbes causing human oral diseases (Streptococcus mutans, Porphyromonas gingivalis, and Candida albicans). The extract was prepared using ethyl acetate and it was treated with the oral microbes at a concentration of 5.00 mg/ml (0.5%). The anti-microbial activity and MIC were measured using broth dilution method. Significant reduction of microbial activities of 16 types of oral microbes occurred when the soybean paste extract was added to the broth compared to the control (p<0.01), and striking inhibition (more than 99%) was observed in ten types. S. mutans, which causes dental caries, showed MIC at a concentration of 1.25 mg/ml for the extract. P. gingivalis, which causes adult periodontal disease, showed MIC at a concentration of 2.50 mg/ml for the extract. C. albicans, which causes denture stomatitis and angular stomatitis, showed MIC at a concentration of 20 mg/ml for the extract. These results indicate that ethyl acetate extract of doen-jang showed strong anti-microbial effect against 16 types of oral microbes, and the anti-microbial effect of the extract against oral microbes was stronger against bacteria than against fungi. The anti-microbial effect might be possibly enhanced by the fermentation of soybeans.

• Proceedings of the Korean Environmental Health Society Conference
• /
• 2004.06a
• /
• pp.182-184
• /
• 2004

Oral cancer is the sixth most common cancer globally. The effects of several extracts from soybeans and Korean soybean paste (doen-jang) on the growth of human oral carcinoma cells in vitro were assessed. We prepared petroleum ether extract, ethyl acetate extract, chloroform extract, methanol extract, and water extract from soybeans and soybean paste. We used KB cell, which is an oral epidermoid carcinoma cell, and investigated proliferation of the tumor cells using MTT method. Each extract of soybean paste suppressed the KB cell proliferation. A dose-response relationship was observed between the level of ethyl acetate extract of soybean paste and its suppression of the cell proliferation. The effects of soybean extracts were lower than those of soybean paste extracts. The effects might be enhanced by the fermentation of soybeans. The results of this work indicate that extracts from soybeans and Korean soybean paste could have potential as anti-tumor substances.

• Journal of Life Science
• /
• v.8 no.5
• /
• pp.473-478
• /
• 1998

The radical scavenging activity of the methanol extracts was in the order of doenjang〉 meju〉 soybean. The metha-nol extracts were further fractionated with dichloromethane, ethyl acetate, butanol and water in sequence. Among the solvent fractions of the methanol extracts, the ethyl acetate fraction demonstrated high levels of radical scave-nging activity. On the other hands, the nitrite scavenging activity of the methanol extrats was in the order of doen-jang〉soybean〉meju. All fractions from doenjang were exhibited the strong nitrite scavenging effect. Especially, $H_2O$, EtOAc and BuOH fractions with 6gmg/10$m\ell$ concentration exhibited much stronger nitrite scavenging effect than that of L-ascorbic acid. The ethyl acetate fraction showed remarkable antioxidant and nitrite scavenging effects compared with the other fractions obtained from soybean, meju and doenjang. The ethyl acetate fraction of doenjang was fur-ther purified by repeated chromoatograpic methods and isolated three compounds. There are identified as genistin, dai-dzein and genistein on the basis of spectral data.