Soybean Sauce Research Articles

Umami Taste Components and Their Sources in Asian Foods

Umami, the fifth basic taste, is the inimitable taste of Asian foods. Several traditional and locally prepared foods and condiments of Asia are rich in umami. In this part of world, umami is found in fermented animal-based products such as fermented and dried seafood, and plant-based products from beans and grains, dry and fresh mushrooms, and tea. In Southeast Asia, the most preferred seasonings containing umami are fish and seafood sauces, and also soybean sauces. In the East Asian region, soybean sauces are the main source of umami substance in the routine cooking. In Japan, the material used to obtain umami in dashi, the stock added to almost every Japanese soups and boiled dishes, is konbu or dried bonito. This review introduces foods and seasonings containing naturally high amount of umami substances of both animal and plant sources from different countries in Asia.

Rapid detection method for aflatoxin B1 in soybean sauce based on fluorescent microspheres probe

Soybean sauce, a Chinese traditional and daily condiment, is often contaminated by aflatoxin B1. An extract-free immunochromatographic assay was proposed based on fluorescent microspheres probe for the' detection of aflatoxin B1 in soybean sauce. The probe was prepared by coupling fluorescent microspheres with anti-aflatoxin B1 antibody by the 1-ethyl-3(3-dimethylaminopropyl) carbodiimides hydrochloride-mediated method. The background from the soybean sauce sample on strip was eliminated because of the optical property of the probe. The sample without extracting procedure was directly detected by diluting with 10% methanol solution. The visible detection limit for the qualitative analysis of aflatoxin B1 in the proposed method was 2.5 μg/L, which was lower than the maximum level of 5 μg/L set by the Chinese government. The results were well agreed with those obtained by liquid chromatography-mass spectrometry (LC-MS). The method showed satisfactory characteristics, such as rapid detection, easy operation, and high sensitivity, and can thus be applied for the large-scale and on-site screening of soybean sauce contaminated with aflatoxin B1. To our knowledge, this report is the first one on the qualitative detection of aflatoxin B1 in dark colored food samples directly by fluorescent microspheres probe-based immunochromatography.

Quantitative Validation of Two Novel Selective Media for the Enumeration of B acillus cereus in Naturally Contaminated Fermented Sauce Samples

We compared two novel selective media, blood–yolk–polymyxin B–trimethoprim agar (BYPTA) and modified mannitol–yolk–polymyxin B agar (mMYPA), with mannitol–yolk–polymyxin B agar (MYPA) for the isolation and enumeration of Bacillus cereus in naturally contaminated Korean fermented sauce samples such as red pepper paste, soybean paste, ssamjang and chunggukjang. A total of 81 fermented sauce samples were purchased from a local retail market in Seoul, South Korea. No statistical differences were observed in quantitative enumeration and isolation rates (P > 0.05) among the three selective media. However, BYPTA and mMYPA exhibited higher selectivity than MYPA in excluding the background microflora. In addition, BYPTA (22/81, 27%) and mMYPA (21/81, 26%) detected more fermented sauces with unacceptable levels of B. cereus than MYPA (16/81, 20%) suggesting that the two novel selective media could be used to efficiently detect unacceptable levels of B. cereus in Korean fermented sauce. The two novel selective media could be powerful tools to enumerate the level of B. cereus in fermented sauce samples that have a high level of background microflora. Practical Applications In previous studies, we developed two novel selective media, BYPTA and mMYPA for the enumeration of Bacillus cereus in foods. It is well known that naturally fermented Korean soybean sauces are commonly contaminated with B. cereus, and a high level of background microflora in these foods could behave competitively during the detection of B. cereus. These sauces are also commonly consumed without additional heat treatment. Therefore, highly specific and sensitive media for the enumerative detection of B. cereus in the fermented sauces are needed. In this study, we found that the two novel selective media exhibited greater selectivities and isolation capabilities for B. cereus in the fermented sauces than MYPA. In addition, BYPTA and mMYPA detected more fermented sauces with unacceptable levels of B. cereus than MYPA. We recommend these two media be used in food manufacturing plants and food safety authorities to monitor B. cereus in fermented sauces that have a high level of background microflora.

Determination of lead in soybean sauces by the diffusive gradients in thin films technique

A diffusive gradients in thin films (DGT) device with sodium poly (aspartic acid) (PASP) as a novel binding agent (PASP DGT) combined with graphite furnace atomic absorption spectrometry (GFAAS) was developed for the sampling and measurement of lead in soybean sauce samples. The performance of PASP DGT was independent of pH in the range of 3–6 and salinity in the range from 4 to 14g/L (as NaCl). There was no significant difference between PASP DGT technique and hydride generation atomic fluorescence spectrometry (HG-AFS) method for the measurement of lead in soybean sauce samples. The recoveries of lead in spiked soybean sauce samples determined by PASP DGT coupled with GFAAS were 94.3–97.2% with the relative standard deviations of 2.52–3.09%. The concentrations of Pb in twelve soybean sauce samples determined by PASP DGT coupled with GFAAS were in the range of 0.09–0.71mg/L.

Optimization of Pretreatment for Free and Bound Nε-(carboxymethyl)lysine Analysis in Soy Sauce

Soy sauce contained free and bound Ne-(carboxymethyl)lysine (CML); however, the CML level in soy sauce was underestimated because of the inappropriate pretreatment in analyzing CML of soy sauce. This study performed quantitative identifications of free and bound CML on soybean sauce samples by high-performance liquid chromatography-mass spectrometry (HPLC-MS). Different pretreatment methods were respectively applied to free and bound CML analysis. C18 solid-phase extraction (SPE) column purification was chosen as the pretreatment method for free CML analysis, the recoveries of standard additions of free CML at 50 and 100 μg/mL were found to be 98.63 ± 0.27 and 98.66 ± 0.56 %, respectively. The optimal pretreatment conditions for bound CML were as follows: soy sauce dosage of 3.0 mg protein and peptide nitrogen equivalent, dialysis bags (molecular weight cutoff, 500 Da) isolation of proteins and peptides, and hydrolysis time of 12 h. The free and bound CML levels in 12 different brands of soy sauce were also analyzed.

중국 내 시판 한식 장류의 품질특성

Sun Young Lee, Soo Hwa Baik, Yu Jin Ahn, Jin Song, Jae Hyun Kim, and Hye Sun Choi*Department of Agro-food Resources, National Academy of Agricultural Science, RDAAbstract Soybean-based fermented foods have been used as traditional condiments in Korea, Japan and China. ThirteenKorean types of soybean sauce that had been manufactured and sold in China were examined to evaluate their quality.The pH, salinity, and moisture content of the samples were pH 5.17-6.86, 8.0%-23.0%, and 46.446-70.40%, respectively.The amino-type nitrogen content was in the range of 199.18 to 736.46 mg%. The total aerobic bacterial counts were 4.83-7.89 Log CFU/g. The coliform count of gochujang (CNH-2) was 2.31 Log CFU/g, but none were detected in the othersamples. Moreover, Bacillus cereus counts from samples of doenjang and gochujang were in the range 2.00-4.09 LogCFU/g. The protease and amylase activity of samples were 379.02-781.36 unit/g and 5.29-63.27 unit/g, respectively.Keywords: China, fermented soybean paste, quality characteristics, fermentation

Preparation and aroma analysis of Chinese traditional fermented flour paste

Volatile compounds in Chinese fermented flour paste were extracted using simultaneous distillation and extraction (SDE) and analyzed using gas chromatography-mass spectrometry (GC-MS) with DB-5 and DB-WAX capillary columns. A total of 84 volatile compounds were identified, including 8 aldehydes, 19 esters, 14 acids, 17 hydrocarbons, 7 heterocycles, and 19 other trace compounds. The major volatiles included furfural, 5-methyl-2-phenyl-2-hexenal, 4-ethylguaiacol, 2-phenylacetaldehyde, ethyl hexadecanoate, isovaleraldehyde, palmitic acid, and 5-methylfurfural. Aroma compounds were investigated using gas chromatography-olfactometry (GC-O) and aroma extract dilution analysis (AEDA). A total of 27 olfactory regions were exposed and 18 aroma extracts were located. Altogether, 6 aroma compounds identified using GC-O showed higher flavor dilution factors (FD≥32), including isovaleraldehyde, furfural, pentanoic acid, 2-acetylfuran, 1-octen-3-ol, and 2-phenylacetaldehyde. Compared with soybean sauce, fermented flour paste has more esters and aldehydes, which contribute to the desired fruity, caramel, sweet, and roasted odors.

Rapid pretreatment and detection of trace aflatoxin B1 in traditional soybean sauce

Soybean sauce, a traditional fermented food in China, has different levels of aflatoxin B1 pollution. Two kinds of direct and indirect immunomagnetic bead methods for the pretreatment of aflatoxin B1 were evaluated in this work. A method was established to detect aflatoxin B1 in soybean sauce using an immunomagnetic bead system for pretreatment and ELISA for quantification. The pretreatment method of immunomagnetic beads performed better compared with the conventional extraction and immunoaffinity column method. ELISA exhibited a good linear relationship at an aflatoxin B1 concentration of 0.05–0.3μg/kg (r2=0.9842). The average recoveries across spike levels varied from 0.5 to 7μg/kg were 83.6–104% with a relative standard deviation between 4.2% and 11.7%. With the advantages of rapid detection, easy operation, simple equipment, sensitivity, accuracy, and high recovery; this method can be well applied in the trace determination of aflatoxin B1 in soybean sauce samples.

Pengaruh Konsentrasi COD Terhadap Efektifitas Pengolahan Air Limbah Secara UASB

A study on effect of various COD concentration of soy-bean sauce wasteweter treatment using UASB type bioreactor has been conducted. The result exhibited that over 90 % of the COD could be removed. Removal rate of COD was not significantly affected by elapsing time of the treatment and for flucatuating COD concentration, however, it appeared to poin out a significant difference as a result of increasing COD level of the feed solution. The higher the COD level was fed, the more the amount of COD was eliminated. The generated gas volume was also raised as the COD Concentration was increased.

Influence of sodium chloride on thermal denaturation of a high-salt-tolerant neutral protease from Aspergillus oryzae

The temperature and pH stability of proteases have been extensively investigated. A neutral protease produced by Aspergillus oryzae was thermodynamically characterized at high-salt environment. When the protease was tested at 24% NaCl and 60 o C, its half-life was increased to 30.0 min, 111% longer than that of control. Its Gibbs free energy and activation energy for denaturation in high NaCl concentration solutions were higher than in low salt solutions and increased by 2.1 and 4.75 kJ/mol, respectively. The protease exhibited higher thermal stability in higher salt conditions. This feature is beneficial to soybean sauce fermentation by enhancing the protease performance and taste of the product. Analysis by far- ultraviolet circular dichroism (far-UV CD) spectroscopy revealed that α-helix conformation in the protease increased from 3.2 to 31.7%, respectively, when the NaCl concentration increased from 0 to 18%, in agreement with the results deduced by thermodynamic calculations.

Formation and destruction of biogenic amines in Chunjang (a black soybean paste) and Jajang (a black soybean sauce)

Chunjang and Jajang samples were analysed for biogenic amine contents by using HPLC equipped with a UV–Vis detector. Chunjang samples contained relatively large amounts of histamine (up to 273mg/kg) and tyramine (up to 131mg/kg), whereas Jajang samples had relatively small amounts of biogenic amines (mostly less than 40mg/kg). There appeared to be a strong relationship between biogenic amine contents in Chunjang and Jajang, and the biogenic amines in Chunjang were found to be pyrolysed during frying thereof to prepare Jajang. Meanwhile, the total plate counts of Chunjang samples ranged from 5 to 8logcfu/g, and most strains that were isolated from Chunjang samples were identified to be Bacillus subtilis (91.0%). The strains isolated from a sample in which relatively small amounts of biogenic amines were detected showed significantly weak abilities to produce biogenic amines. This indicates that biogenic amine contents in Chunjang are primarily attributed to bacterial abilities to produce biogenic amines.

An Outbreak of Food Borne Illness Due to Methomyl Pesticide Intoxication in Korea

On February 21, 2013, 6 elderly people collapsed abruptly after eating bean sprout bibimbab (boiled rice mixed with bean sprouts and seasoned with soybean sauce) at a countryside restaurant in the Chungbuk Province, Korea. Minutes after eating the meal, all of the patients lapsed into a state of stupor. Respiratory arrest developed in 2 patients; and one of two patients died of cardiac arrest. The autopsy identified methomyl and methanol in the deceased patient's gastric contents and in the remaining soybeanbean sauce seasoning. Five of the 6 patients ingested one spoonful of the soybeanbean sauce seasoning and survived, while one patient who died of cardiac arrest, ingested approximately two spoons. Symptoms of toxicity presented quickly in the subjects and progressed rapidly, including chest tightness, an unusual sensation in the pit of the stomach, dizziness, ataxia, and finally, collapse. Three patients who drank ethanol with the meal experienced only mild toxic symptoms. Our analysis of the clinical observations in these cases suggests that ingestion of methomyl pesticide and the additive toxicity of methanol may have been responsible for the intoxication.

간장을 이용한 저염 야콘 장아찌의 품질특성

To evaluate the possibility of low-salinity of traditional fermented food, we investigated quality characteristic of low-salted Yacon Jangachi using soybean sauce with sugar or vinegar for 50 days. Sugar content, titration acidity, and salinity of all Yacon Jangachi was increased as storage time increased. All of the Yacon Jangachi had less than 3.0% salinity. Especially, the salinity of the Yacon Jangachi with sugar and vinegar was the lowest during storage time. The L value was decreased as storage time increased but the results of the a and b values were reversed. Cutting force was not significant among samples and storage periods. In the results of sensory evaluation, preference of all samples were increased as storage time increased. The preference of color was not significant among samples from 30 days but the taste was reversed. The preference of flavor was significant between samples in 40 days, texture was not significant during storage time. Overall preference was not significant after 30 days, which suggested that Yacon Jangachi using soybean sauce retains overall preference in steady level from 30 days. Yacon Jangachi using soybean sauce showed the highest preference when produced with sugar and vinegar.

Effects of Salt Concentration in Soybean Sauce on the Physicochemical Properties of Pre-rigor Ground Hanwoo Muscle

This study was conducted to examine the effect of salt concentration in soybean sauce (ganjang) on pre-rigor ground Hanwoo (Korean native cattle) muscle. Although adding soybean sauce reduced pH of pre-rigor Hanwoo muscle, it improved the water holding capacity (WHC), cooking loss, total protein solubility, myofibrillar fragmentation index (MFI), 2-thiobar-bituric acid (TBA) values, and textural properties by increasing salt concentration in the soybean sauce. In particular, adding soybean sauce inhibited lipid oxidation despite increasing salt concentration. An increased salt concentration in the soybean sauce in pre-rigor Hanwoo muscle tended to make the meat have lower lightness and higher redness and yellowness values. Although soybean sauce had a significantly lower pre-rigor salting effect than sodium chloride in terms of cooking loss and total protein solubility (p<0.05), soybean sauce improved myofibrillar fragmentation and lipid oxidation when compared with sodium chloride. Furthermore, no significant differences in textural properties were observed between adding soybean sauce and sodium chloride at the same salt concentrations. Therefore, soybean sauce can be a functional curing material for pre-rigor muscle.

Effects of Soybean Sauce and Pre-rigor Muscle on Physicochemical Properties of Frozen Hanwoo Patties

In this study, we evaluated the physicochemical and sensorial properties of frozen Hanwoo beef patties prepared from prerigor and post-rigor muscle with soybean sauce or sodium chloride. The pH of the soybean sauce treatments was lower than the sodium chloride treatments (p<0.05); however, the Hanwoo patty prepared from pre-rigor muscle with soybean sauce had a lower cooking loss and smaller diameter than the Hanwoo patty prepared under the same conditions from post-rigor muscle (p<0.05). The addition of the soybean sauce inhibited lipid oxidation due to the antioxidative materials in soybean sauce such as melanoidin. The hardness of patties prepared from pre-rigor treatment was lower relative to those prepared from post-rigor muscle (p<0.05); however, there was no significant difference between springiness, cohesiveness, and chewiness (p>0.05). In the sensory evaluation, patties prepared from pre-rigor muscle with soybean sauce had a significantly high score in all traits (p<0.05); thus, pre-rigor muscle with soybean had the highest overall acceptability. Furthermore, the addition of soybean sauce to pre-rigor muscle produced similar effects as those observed for the addition of sodium chloride in regards to psychochemical properties. Moreover, meat products produced from pre-rigor muscle will have better antioxidative and sensorial properties.

The Operation Time Influence on the Sauce Wastewater Treatment

With rapid development of food industry, the production of soybean sauce is increasing in recent years. The sauce wastewater is doing greater and greater harm to the water environment. In order to tackle this problem, the operation time on the sauce wastewater treatment were investigated. The results showed that the process has a better effect for ammonia nitrogen, the orthophosphate and COD removal. The effluent ammonia nitrogen was less than 5mg/L and the ammonia nitrogen removal efficiency could reach about 90% with the aeration time 2 h-3.5 h. The orthophosphate increased during the anoxic stage while decreased during the aerobic stage. At the end of the aerobic stage, the orthophosphate concentration and the COD could reach about 1mg/L and 21 mg/L respectively when aeration time was 2 h-3.5 h. The better operation time (the aeration time) was at 2 h-3.5 h and the system could get a good water quality for sauce wastewater treatment.

'Soybean sauce' peritoneal dialysate.

A 68-year-old woman with end-stage diabetic nephropathy undergoing continuous ambulatory peritoneal dialysis for 2 years was admitted for septic shock with coma, who was found hours earlier. Physical examination revealed an unconscious febrile woman with blood pressure of 84/49 mm Hg. Blood tests showed a haemoglobin of 11.5 (normal 12–15) g/dL, white blood cell (WBC) count of 11.3 (normal 3.8–9.8) × 109/L with 82% of segmented neutrophils, high creatine kinase level of 3050 (normal 20–170) U/L, as well as elevated aspartate aminotransferase (198, normal 11–45 U/L) and alanine aminotransferase level (117, normal 7–50 U/L). The peritoneal dialysate was initially clear, but became reddish-brown (Figure 1A) with a red blood cell (RBC) count of 1/μL and WBC 12/μL at the next exchange several hours later, and progressed to ‘soybean sauce’-like (Figure 1B) on the second hospital day when the analysis demonstrated an occult blood reaction of 3 + by dipstick, RBC 14/μL, WBC 200/μL with neutrophils 83%, bilirubin 0.1 mg/dL, along with a serum haemoglobin of 10.5 g/dL. Despite intensive management with potent intravenous antibiotics and high-dose inotropic agents, the patient died on the third hospital day. The dialysate kept the same appearance without precipitation even after being stored for 7 days. Fig. 1 The peritoneal dialysate of a 68-year-old uraemic woman undergoing continuous ambulatory peritoneal dialysis with septic shock and rhabdomyolysis became reddish-brown a few hours after admission (A) and progressed to ‘soybean sauce’-like ... The abundant peritoneal dialysable [1] myoglobins from progressive rhabdomyolysis precipitated by long-term immobilization and profound septic shock [2] in our patient are favoured to have caused the ‘soybean sauce’ dialysate because of the strongly positive occult blood reaction with only 14 RBC/μL in the dialysate. The nearly constant serum haemoglobin level and extremely low dialysate bilirubin level further convincingly excluded the possibility of intra-abdominal bleeding and bile leakage, respectively. The discoloured peritoneal dialysate by myoglobin is rarely described. Another interesting report is the ‘cola-coloured’ effusion in a peritoneal dialysis patient suffering from rhabdomyolysis with a dialysate myoglobin level of 20 406 μg/L [3]. Conflict of interest statement. None declared.

Differential heat stability of amphenicols characterized by structural degradation, mass spectrometry and antimicrobial activity

Heat stability of amphenicols and the relationship between structural degradation and antimicrobial activity after heating has not been well investigated. Florfenicol (FF), thiamphenicol (TAP), and chloramphenicol (CAP) were heated at 100 °C in water, salt water, soybean sauce and chicken meat for up to 2 h. Degradation and antimicrobial activity of the compounds was evaluated using capillary electrophoresis (CE) with UV-DAD spectrometry, minimum inhibitory concentration (MIC) assay, and gas chromatography with electron impact ionization mass spectrometry (GC–EI-MS). Heat stability of amphenicols in matrices was ranked as water ≥ salt water > soybean sauce > meat, suggesting that heat degradation of amphenicols was accelerated in soybean sauce and was not protected in meat. Heat stability by drug and matrices was ranked as FF > TAP = CAP in water, FF = TAP > CAP in salt water, TAP ≥ FF = CAP in soybean sauce, and TAP ≥ FF = CAP in meat, indicating differential heat stability of amphenicols among the 3 drugs and in different matrices. In accordance with the less than 20% degradation, the MIC against Escherichia coli and Staphylococcus aureus did not change after 2 h heating in water. A 5-min heating of amphenicols in water by microwave oven generated comparable percentage degradation to boiling in water bath for 30 min to 1 h. Both CE and GC–MS analysis showed that heating of FF produced TAP but not FF amine as one of its breakdown products. In conclusion, despite close similarity in structure; amphenicols exhibited differential behavior toward heating degradation in solutions and protein matrices. Although higher degradations of amphenicols were observed in soybean sauce and meat, heating treatment may generate product with antimicrobial activity (FF to TAP), therefore, heating of amphenicol residues in food cannot always be assumed safe.

Risk Assessment of Soybean-Based Phytoestrogens

Koreans generally consume high quantities of soybean-based foods that contain a variety of phytoestrogens, such as, daidzein, zenistein, and biochalin A. However, phytoestrogens are considered to be potential endocrine-disrupting chemicals (EDC), which interfere with the normal function of the hormonal and reproductive systems. Therefore, dietary exposure to soybean-based phytoestrogens is of concern for Koreans, and comparative dietary risk assessments are required between Japanese (high consumers) versus Americans (low consumers). In this study, a relative risk assessment was conducted based upon daily intake levels of soybean-based foods and phytoestrogens in a Korean cohort, and the risks of photoestrogens were compared with those posed by estradiol and other EDC. Koreans approximately 30–49 yr of age consume on average a total of 135.2 g/d of soy-based foods including soybean, soybean sauce, soybean paste, and soybean oil, and 0.51 mg/kg body weight (bw)/d of phytoestrogens such as daidzein and genistein. Using estimated daily intakes (EDI) and estrogenic potencies (EP), margins of safety (MOS) were calculated where 0.05 is for estradiol (MOS value <1, considered to exert a positive estrogenic effect); thus, MOS values of 1.89 for Japanese, 1.96 for Koreans, and 5.55 for Americans indicate that consumption of soybean-based foods exerted no apparent estrogenic effects, as all MOS values were all higher than 1. For other synthetic EDC used as reference values, MOS values were dieldrin 27, nonylphenol 250, butyl benzyl phthalate 321, bisphenol A 1000, biochanin A 2203, and coumesterol 2898. These results suggest that dietary exposure to phytoestrogens, such as daidzein and genistein, poses a relatively higher health risk for humans than synthetic EDC, although MOS values were all greater than 1.

간장에서 분리한 Bacillus licheniformis가 생산하는 박테리오신의 특성 및 정제

수집한 간장시료에서 형태학적인 특성에 따라 상이한 30주의 미생물을 분리하고 MRS 액체배지에서 <TEX>$37^{\circ}C$</TEX>, 24시간 배양한 후 회수한 배양 상등액 중 paper disc법으로 항균활성이있는 것을 일차 선별하여 proteinase K 처리에 의해 항균활성이 사라지는 시료 하나를 최종적으로 선별하였다. 선별한 분리주를 생화학적 분류와 분자계통학적 분류를 통해 동정한 결과 B. lichenifirnus로 나타났다. 이 균주의 생장온도와 배지의 초기 pH 에 따른 세포생장 및 박테리오신 활성을 조사한 결과 배양온도는 <TEX>$37^{\circ}C$</TEX>, 배지의 초기 pH는 7.0에서 박테리오신의 활성이 가장 높게 나타났다. B. lichenifirnus가 생산하는 박테리오신은 Bacill sogaerucey, Lactobacillus bulgaricus, Lactobacillus plantaum, Micrococcus Iateus, Paenibacillus polymyxa 및 Pediococcus dextrinicus 등에 대해서 항균활성을 보였으며, pH 3.0<TEX>${\sim}$</TEX>11.0에 이르는 거의 전 pH 영 역에서 20시간 이상 처리하여도 그 항균활성을 완전히 잃지 않아 비교적 넓은 pH 범위 내에서 안정함을 알 수 있었다. Acetone, acetonitrile, chloroform, ethanol 처리 및 <TEX>$20{\sim}100^{\circ}C$</TEX>C에서 60분간 가열시에도 높은 항균활성을 유지하였다. 여러 가수분해효소에 대한 내성을 조사한 결과 trypsin, a-chymotrypsin, pepsin, a -amylase 및 carboxypeptidase A 등은 항균활성에 영향을 주지 않았으나 lipase는 항균활성을 약간 감소시켰으며 proteinase K는 항균활성을 완전히 사라지게 하였다. 75% 황산암모늄 침전, 양이온교환크로마토그래피, 역상 HPLC 등의 과정을 통해 정제된 박테리오신의 상대비활성(specific activity)은 배양상등액에서 보다 약 75배 증가하였고 회수율은 13.5%였다. 역상 HPLC를 통해서 정제된 박테리오신의 분자량을 tricine SDS-PAGE을 통해서 확인한 결과 약 2.5 kDa으로 나타났으며 염색 시 단일 band로 나타나 순수하게 정제되었음을 확인하였다. A bacteriocin-producing bacterium identified as Bacillus licheniformis was isolated from soybean sauce. Antibacterial activity was confirmed by paper disc diffusion method, using Micrococcus luteus as a test organism. The bacteriocin also showed antibacterial activities against Bacillus sphaericus, Lactobacillus bulgaricus, Lactobacillus planiarum, Paenibacillus polymyxa, and Pediococcus dextrinicus. Optimal culture conditions for the production of bacteriocin was attained by growing the cells in an MRS medium at a pH of 6.5~ 7.0 and a temperature of 37<TEX>$^\circ$</TEX>C for 36<TEX>$\sim$</TEX>48 hr. Solvents such as chloroform, ethanol, acetone, and acetonitrile had little effect on bacteriocin activity. However, about 50% of bacteriocin activity diminished with treatment of methanol and isopropanol at the final concentration of 50% at 25<TEX>$^\circ$</TEX>C for 1 hr. It was stable against a pH variation range from 3.0 and 7.0, but the activity reduced to 50% at a pH range from 9.0 to 11.0. It's activity was not affected by heat treatment at 100<TEX>$^\circ$</TEX>C for 30 min and 50% of activity was retained after heat treatment at 100<TEX>$^\circ$</TEX>C for 60 min, showing high thermostability. The bacteriocin was purified to a homogeneity through ammonium sulfate precipitation, SP-Sepharose ion-exchange chromatography, and reverse-phase high-performance liquid chromatography (HPLC). The entire purification protocol led to a 75-fold increase in specific activity and a 13.5% yield of bacteriocin activity. The molecular weight of purified bacteriocin was estimated to be about 2.5 kDa by tricine-SDS-PAGE.