• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.936-940
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• 2004

Doenjang (Korean soy paste) is one of the popular soybean based fermented foods in Korea. This study investigated the growth and DNA synthesis inhibitory effect of doenjang methanol extracts on AGS human gastric adenocarcinoma cells, Hep 3B human hepatocellular carcinoma cells and HT-29 human colon cancer cells. In order to determine an anticancer effect of doenjang methanol extracts, other soybean fermented foods and original materials were compared. The treatment of doenjang methanol extracts (200 $\mu\textrm{g}$/mL) to the AGS, Hep 3B and HT-29 cancer cells inhibited the growth of cancer cells by 80%, 77% and 86%, respectively. Compared to other soybean fermented foods and original materials, doenjang methanol extracts showed the highest growth inhibitory effect on different cancer cells. In addition, doenjang methanol extracts (200 $\mu\textrm{g}$/mL) significantly inhibited DNA synthesis of AGS and Hep 3B cancer cells by 76% and 59%, respectively. These results suggested that this anticancer effect of doenjang may be due to specific active compounds, which will be newly produced during soybean fermented process and not contained in soybean.

• Journal of Applied Biological Chemistry
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• v.51 no.3
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• pp.88-94
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• 2008

Three different protein extraction methods-phenol extraction, trichloroacetic acid (TCA) precipitation, and desalting/TCA precipitation-were compared to determine the optimal reproducible high resolution 2-dimensional (2-D) electrophoresis for each chungkugjang, doenjang, and kochujang samples. The soluble proteins from Chungkugjang extracted by phenol were separated with high reproducibility and resolution, and gained 1.75- to 3-fold more protein spots on 2-D gel than those from the other methods. On the contrary, the extracted proteins from doenjang and kochujang treated by desalting/TCA precipitation method showed about 1.5- to 3.3-fold more protein spots on 2-D gel. Using the established methods, the changes in the protein profiles of the fermented soy foods were monitored during the fermentation period by 2-DE. One of the major proteins in soy, $\beta$-conglycinin $\alpha$-subuint, and some proteins with unknown functions were localized on 2-D gel as the protease-resistant proteins throughout the fermentation period of doenjang. Changes in the protein profile monitored by the established methods can provide basic information on unfolding the mechanisms of the generation of biofunctional activity in the fermented soy foods.

• Nutrition Research and Practice
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• v.9 no.3
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• pp.235-241
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• 2015

BACKGROUND/OBJECTIVES: Doenjang, Korean traditional fermented soybean paste has been reported to have an anti-obesity effect. Because adipose tissue is considered a major source of inflammatory signals, we investigated the protective effects of Doenjang and steamed soybean on oxidative stress and inflammation in adipose tissue of diet-induced obese mice. MATERIALS/METHODS: Male C57BL/6J mice were fed a low fat diet (LF), a high-fat diet (HF), or a high-fat containing Doenjang diet (DJ) or a high-fat containing steamed soybean diet (SS) for 11 weeks. RESULTS: Mice fed a DJ diet showed significantly lower body and adipose tissue weights than those in the HF group. Although no significant differences in adipocyte size and number were observed among the HF diet-fed groups, consumption of Doenjang alleviated the incidence of crown-like structures in adipose tissue. Consistently, we observed significantly reduced mRNA levels of oxidative stress markers (heme oxygenase-1 and $p40^{phox}$), pro-inflammatory adipokines (tumor necrosis factor alpha and macrophage chemoattractant protein-1), macrophage markers (CD68 and CD11c), and a fibrosis marker (transforming growth factor beta 1) by Doenjang consumption. Gene expression of anti-inflammatory adipokine, adiponectin was significantly induced in the DJ group and the SS group compared to the HF group. The anti-oxidative stress and anti-inflammatory effects observed in mice fed an SS diet were not as effective as those in mice fed a DJ diet, suggesting that the bioactive compounds produced during fermentation and aging may be involved in the observed health-beneficial effects of Doenjang. CONCLUSIONS: Doenjang alleviated oxidative stress and restored the dysregulated expression of adipokine genes caused by excess adiposity. Therefore, Doenjang may ameliorate systemic inflammation and oxidative stress in obesity via inhibition of inflammatory signals of adipose tissue.

• Food Science and Industry
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• v.50 no.4
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• pp.24-49
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• 2017

Volatile flavor compounds of cheonggukjang and doenjang, which are the most representative Korean soybean fermented foods, were compiled throughout literature review. Total of 225 and 404 volatile flavor compounds were found in cheonggukjang and doenjang, respectively. The most characteristic volatile flavor compounds in cheonggukjang are thought to be pyrazine compounds. In addition, acids, such as 2-methyl propanoic acid, butanoic acid, 2-methyl butanoic acid, and 3-methyl butanoic acid, contribute to aroma characteristics of cheonggukjang. On the other hand, ester compounds are the most predominant volatile flavor compounds in doenjang. Ninety six ester compounds were detected in doenjang while 22 ester compounds were identified in cheonggukjang. Pyrazine compounds and acids also play an important role in the flavor of doenjang. Compilation of volatile flavor compounds from cheonggukjang and doenjang will provide basic information to food industry to understand and improve aroma characteristics of cheonggukjang and doenjang.

• Journal of the Korean Society of Food Culture
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• v.22 no.3
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• pp.353-358
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• 2007

This study was conducted to compare the antioxidant activities of fermented soy products such as chungkukjang, meju and doenjang with soybeans. Total phenolic, flavonoids contents and antioxidative activities of the methanol extract of soy and fermented products were compared with specific reference to alpha-diphenyl-2-picryl-hydrozyl (DPPH) radicals scavenging effects, ferric /reducing power (FRAP), inhibition of conjugated diene formation and tyrosinase activities. Total phenolic and flavonoids contents increased in soybeans after fermentation. Fermented soy products also displayed enhanced antioxidative activities in comparison with the non-fermented soybeans. There were linear relationships between total phenolic and flavonoids contents and ferric reducing/antioxidant power of the samples. Overall, the fermented soy products showed a better antioxidant activity than soybeans. Among the 3 kinds of fermented soy products, chungkukjang, meju and deonjang, doenjang exhibited the highest levels of DPPH-free radicals scavenging activity, ferric /reducing power, inhibition of conjugated diene formation and tyrosinase activities. The fermented soy products with longer fermentation time demonstrated the higher antioxidant activities as well as higher total phenols and flavonoids in the order of doenjang > meju > chunghlkjang> soybeans.

• Journal of the Korean Society of Food Culture
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• v.35 no.5
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• pp.467-477
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• 2020

Doenjang is a major fermented soy-based food in Korea. Recent investigations have shown that fermented soybean foods have immunity-enhancing, anti-cancer, anti-obesity and anti-diabetic effects. Several studies also have reported that genistein and daidzein, which are easily absorbed in the body are produced in larger quantities in aged doenjang. The purpose of this study was to evaluate the variations in the anti-cancer effects of commercialized doenjang as it ages. Four groups were formed for this study according to aging periods of doenjang, namely short (under 5 years, S group), mid (under 10 years, M group), long (under 15 years, L group) and very long (over 15 years, E group). The anti-cancer effects of doenjang were determined by cell cytotoxicity assays in A549, YAC-1, and HepG2 cancer cell lines. Also, NK cell activity and splenocyte proliferation were assayed for cancer immunotherapy. The quantities of phenolic compounds in doenjang at different ages were also measured. The results showed that the anti-cancer effects increased in the S and M groups for all three cancer cell lines. Interestingly, similar to this result, splenocyte proliferation and NK activity were also the highest in the S and M groups. In contrast, the E group showed significantly reduced splenocyte proliferation. The quantity of phenolic compounds was similar to that of the anti-cancer results. Collectively, these results suggest that the fermentation period of doenjang plays a very important role in determining its anti-cancer effects.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1503-1510
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• 2007

This study was carried out to investigate antioxidant substances (phenolic compounds and brown pigment), antioxidative effect and nitrite scavenging ability (NSA) of solvent extracts (hexane: HE, methanol; ME, water: WE) from fermented soybean foods, Chungkukjang and Doenjang. The antioxidant activities were determined by the measurements of peroxide value (POV) on the linoleic acid system, electron donating ability (EDA) and superoxide dismutase (SOD)-like activity. The contents of phenolic compounds and total brown pigments in Doenjang were $28.5{\pm}0.3mg/100g$ and optical density (OD) $1.98{\pm}0.03$, respectively, whereas their contents in Chungkukjang were significantly lower with $5.8{\pm}0.3mg/100g$ and OD $0.95{\pm}0.02$. The brown pigment contents of hydrophilic extracts increased more than that of lipophilic extracts through the fermentation and ripening processes. The ME of Doenjang exhibited higher inhibitory effects against the peroxidation of a linoleic acid system than that of Chungkukjang. The EDA and NSA of MEs were higher than those of WEs. Among the MEs, Doenjang showed the highest levels of EDA and NSA. On the other hand, the SOD-like activities of WE were higher than those of ME at the same concentrations and their activities of Doenjang were significantly higher than that of Chungkukjang. In conclusion, the antioxidative effects and NSA of Doenjang was significantly higher than those of Chungkukjang. It seemed that phenolic compounds and brown pigments formed during fermentation and ripening partly affect the antioxidative activities of fermented soybean foods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.240-245
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• 1999

Growth inhibitory effect of doenjang(Korean soypaste) methanol extracts in SRB assay using AGS human gastric adenocarcinoma cell, Hep 3B human hepatocellular carcinoma cell and HT 29 human colon cancer cell was studied. The treatment of doenjang methanol extracts(2mg/assay) to the AGS, Hep 3B and HT 29 cancer cells inhibited the growth of the cancer cells by 55%, 60%, and 71%, respectively. Doenjang methanol extracts exhibited the highest inhibitory effect among other soybean fermented foods and original materials in the SRB assay. In addition, to separate active compounds of doenjang methanol extracts, we fractionated the doenjang with hexane, methanol, dichloromethane, ethylacetate and butanol. Growth inhibitory effect on the AGS, Hep 3B, HT 29 and MG 63 cancer cells was the highest in the fractions of dichloromethane and ethylacetate among other solvent fractions of the doenjang. These results showed that some compounds contained in the fractions of dichloromethane and ethylacetate might play a role on the anticanceric effect of doenjang.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.525-528
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• 1996

To investigate the inhibitory effect of soybean and Korean traditional fermented soybean products on the chemically induced mutagenesis, we extracted soybean, Kanjang, Doenjang, Kochujang, and Chongkukjang with water, methanol and hexane. Inhibitory effect of the extracts was assayed by the SOS chromotest using Escherichia coli PQ37 as a test strain. 4-nitroquinoline-1-oxide(4NQO), N-methyl-N'-nitro-N-nitrosoquanidine(MNNG), and aflatoxin B$_{1}$(AFB$_{1}$) were used as mutagens. Methanol extracts showed relatively higher inhibitory effect than water and hexane extracts. Methanol extracts of soybean, Doenjang, Kochujang, and Chonhkukjang showed inhibitory effect of 68.4, 96.3, 17.5, and 100.9% against MNNG, and 28.6, 109.1, 41.3, and 101.8% against AFB$_{1}$, respectively. Doenjang methanol extract showed inhibitory effect of 51.0, 96.3, and 109.1% against 4NQO, MNNG, and AFB$_{1}$, respectively. Methanol extract of Doenjang showed dose-dependent inhibitory effect against 4NQO, MNNG, and AFB$_{1}$. Inhibitory effect of heat-treated Doenjang and Chongkukjang methanol extracts on the mutagenecity of MNNG and AFB$_{1}$ was remained over 95% of the inhibitory effect of heat-untreated extracts, demonstrating the heat stability of the potent antimutagenic activity.

• Microbiology and Biotechnology Letters
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• v.25 no.5
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• pp.477-482
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• 1997

To investigate the cytotoxicity of Korean traditional fermented soybean products using the MTT assay, we extracted soybean, Kanjang, Doenjang, Kochujang, and Chongkukjang with water, methanol, and hexane. Primary testing of cytotoxicity of 14 extracts was done for P388D1(mouse lympoid neoplasm) and L1210(mouse leukemia) cell lines. Doenjang methanol extract, Kochujang hexane extract, Chongkukjang methanol extract, and Chongkukjang hexane extract showed cytotoxicity of 86.1, 94.3, 83. 6, and 81.1%, respectively against P388D1, and showed cytotoxicity of 69.4, 96.9, 51.4, and 95.1%, respectively against L1210. All the other extracts showed less than 50% cytotoxicity. Methanol extracts of Doenjang and Chongkukjang showed dose-dependent cytotoxicity against P388DI, L1210, SNU-16 (human stomach cancer), HepG2(human hepatic cancer), WiDr(human colon cancer) cell lines, and IC$_{50}$ of Doenjang methanol extract was 67.7, 90.4, 1338.0, 706.4, and 371.2 $\mu$g/ml, respectively, and IC$_{50}$ of Chongkukjang methanol extract was 107.1, 228.3, 756.2, 1346.0, and 327.0 $\mu$g/ml, respectively.