• Journal of Microbiology and Biotechnology
• /
• v.15 no.1
• /
• pp.80-85
• /
• 2005

Electrochemical control of the metabolic flux of W. kimchii sk10 on glucose and pyruvate was studied. The growing cell of W. kimchii sk10 produced 87.4 mM lactate, 69.3 mM ethanol, and 4.9mM lactate from 83.1mM glucose under oxidation condition of the anode compartment, but 98.9 mM lactate, 84.3mM ethanol, and 0.2 mM acetate were produced from 90.8 mM glucose under reduction condition of the cathode compartment for 24 h, respectively. The resting cell of W. kimchii sk10 produced 15.9 mM lactate and 15.2 mM acetate from 32.1 mM pyruvate under oxidation condition of the anode compartment, and 71.3 mM lactate and 3.8 mM acetate from 79.8mM pyruvate under reduction condition of the cathode compartment. The redox balance (NADH/$NAD^+$) of metabolites electrochemically produced from pyruvate was 1.05 and 18.76 under oxidation and reduction conditions, respectively. On the basis of these results, we suggest that the neutral red (NR) immobilized in bacterial membrane can function as an electron channel for the electron transfer between electrode and cytoplasm without dissipation of membrane potential, and that the bacterial fermentation of W. kimchii sk10 can be shifted to oxidized or reduced pathways by the electrochemical oxidation or reduction, respectively.

• Asian-Australasian Journal of Animal Sciences
• /
• v.19 no.3
• /
• pp.386-389
• /
• 2006

Silage is a major component of cattle rations, so the improvement of silage quality by the inoculation of lactic acid bacteria is of great interest. In this study, commercially distributed Lactobacillus plantram and Lactobacillus rhamnousas NGRI 0110 were used for ensilaging of guinea grass. The four treatments used were a control silage, a silage with cellulase addition, a silage with cellulose+L. plantram addition, and a silage with cellulose + NGRI 0110 addition. Silage quality, voluntary intake, nutrient digestibility, and the characteristics of ruminal fluid of wethers were investigated. Silage to which lactic acid bacteria were added showed low pH and acetic acid concentration and the highest lactic acid content. Dry matter and organic matter digestibility were significantly (p<0.05) increased by cellulase addition and significantly (p<0.05) higher values were observed in L. plantram- and NGRI 0110-added silage. Voluntary intake of NGRI 0110-added silage was the highest and that of control silage was the lowest. We concluded that the observed ability of NGRI 0110 to tolerate low pH and to continue lactic acid fermentation in high lactic acid concentration had also occurred in actual ensilaging. The results indicate that the addition of lactic acid bacteria might improve silage quality and increase digestibility and voluntary intake. The potential for improvement by NGRI 0110 was higher than that to be gained by the use of commercially available lactic acid bacteria.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.29 no.4
• /
• pp.629-634
• /
• 2000

The effects of gamma irradiation on changes of chemical compounds of fermented shromp with low salt were studied. The shirmp was salted NaCl concentration of 10%, 15% and 20%, and irradiated at 0, 2.5, 5.0, 7.5 and 10.0kGy. Amino nitrogen (AN), volatile basic nitrogen (VBN), trimethylamine (TMA) and neutral protease acivity were examined during ferentation at 15$^{\circ}C$. A sample with 30% salt concontration was also prepared as a control. The initial contents of AAN, VBN, TMA and protease acitivity were not affected by gamma irradiation. The contents of AN, VBN and TMA were incteased with fermentation period. But, the more increased NaCl concentrations and the higher irradiation dose, the loss increased content of chemical compounds and protease activity were found. Protease was increased until 4~5 weeks and then decreased gradually. The results showed that the chemical compounds and protease activity of salted abd fermeted shrimp prepared with 15% NaCl contentration and 10 kGy irradiation dose, or 20% and 5 kGy or higher were maintained the appropriate level of quality up to 10 weeks of storage compared with the control.

• Toxicological Research
• /
• v.20 no.2
• /
• pp.173-177
• /
• 2004

This study was conducted to investigate the pathogenicity and acute single toxicity of Lactobacillus spp. PSC101 (PSC101) isolated from pigs and L. acidophilus (LA) at 2.5$\times$$10^9$CFU or 2.5$\times$$10^{12}$colony forming units (CFU) in mice for 14 days. After oral administration of the bacteria into mice, we could not find their any specific pathogenicity from the standpoints of clinical signs, and changes in body weight and body temperature, as compared with the control group during 14 days. We further investigated the toxicity of concentrated culture broth ($\times$10) after fermentation of them for safe industrial process. As the results, we could not find any clinical signs, changes in body weight and body temperature, as compared with the control group (MRS broth) for 14 days. The results obtained in this study suggest that the potentially probiotic, PSC101, is non-toxic in mice and is therefore likely to be safe for pig use.

• Korean journal of food and cookery science
• /
• v.18 no.2
• /
• pp.206-210
• /
• 2002

The bread qualities were analyzed objectively by using CrumbScan software. Samples were prepared at the same conditions of mixing, fermentation, and baking time except the amount of Korean wheat flour (KWF). The bread volume was increased with increasing KWF, and the maximum volume was attained in the product of 20% KWF. Although the products of 20% and 30% KWF showed the same thickness of the crust, the crust was thinner than control when KWF was added. The size (fineness) and shape (elongation) of crumb cells were larger and rounder than control due to the low degree of elasticity of the KWF-added dough. Among the samples, the product with 20% KWF showed the most even distribution of crumb cells around the sliced area. The precise determination of external and internal characteristics of the bread was possible with Crumbscan, suggesting the possibility of developing industrial standards for bread.

• The Korea Journal of Herbology
• /
• v.26 no.4
• /
• pp.101-107
• /
• 2011

Objectives : Socheongryong-Tang (小靑龍湯, SCRT) has been widely used to treat respiratory disease. In this study, we investigate the acute toxicity and safety of fermented Socheongryong-Tang extract. Methods : To evaluate the acute toxicity and safety, 0 (control group), 1250, 2500 and 5000 mg/kg of Socheongryong-Tang and fermented Socheongryong-Tang extracts were orally administered to male and female ICR mice. After single administration, we observed survival rates, general toxicity, changes of body weight for the 14 days and autopsy. Results : Compared with the control group, we could not find any toxic alteration in all treated group (1250, 2500 and 5000 mg/kg). Conclusions : $LD_{50}$ of Socheongryong-Tang and fermented Socheongryong-Tang extracts might be over 5000 mg/kg and it is safe to ICR mice.

• Journal of the East Asian Society of Dietary Life
• /
• v.24 no.6
• /
• pp.862-874
• /
• 2014

Salt-fermented fish and fish sauce are very important materials to make Kimchi. They provide good taste and plenty of nutrition to Kimchi during fermentation. However, it is difficult to purchase Korean salt-fermented fish or fish sauce out of Korea. Therefore, to generalize Kimchi for other countries, this research carefully compared the quality differences between Kimchi made with South East Asian fish sauce, which is fairly similar to traditional Korean salt-fermented anchovy extract (Aekjeot) in terms of taste and ingredients, and that made with traditional Korean salt-fermented anchovy extract. To determine quality differences among traditional Korean Kimchies made with different sauces, Korean-made salt-fermented shrimp, salt-fermented shrimp extract, salt-fermented anchovy and salt-fermented anchovy extract were used. Of the four Kimchis, the one made with salt-fermented anchovy extract was chosen as a control sample and compared with those made with three different South-East Asian fish sauces. In the sensory evaluation for acceptance of fish sauces, characteristics of taste, texture and overall acceptance showed significant differences. In the sensory evaluation for differences, characteristics of fish odor and crunchiness showed visible differences. For umami taste, all fish sauces received higher points than Korean salt-fermented anchovy extract (control sample), although the difference was not significant. Sensory evaluation and research results show that Kimchi can become a highly likable food overseas and Kimchi can substitute easily bought South-East Asian fish sauces for Korean salt-fermented fish sauces (Jeotkal).

• Korean Journal of Food Science and Technology
• /
• v.31 no.1
• /
• pp.263-266
• /
• 1999

Pectic substances are important to sustain the textural properties of kimchi during fermentation and distribution. Therefore proper control of pectin degrading enzyme activity is critical on quality control in kimchi industry. Pectin degrading enzymes of kimchi ingredients were assayed to improve the product quality. Among pectin degrading enzymes, polygalacturonase and pectinesterase were selected. The specific activity of polygalacturonase was the highest in salted and fermented anchovy, followed by chinese radish. Considering the amount of protein contents, salted and fermented anchovy and dried red pepper showed higher polygalacturonase activity than other ingredients. In terms of specific activity, chinese radish showed the highest pectinesterase activity, followed by salted and fermented anchovy. However, the total activity of salted and fermented anchovy was the highest. Chinese radish showed higher pectinesterase activity than any other ingredients.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.2
• /
• pp.306-315
• /
• 2017

Metabolic engineering with a high-yielding mutant, A. terreus AN37, was performed to enhance the production of itaconic acid (IA). Reportedly, the gene cluster for IA biosynthesis is composed of four genes: reg (regulator), mtt (mitochondrial transporter), cad (cis-aconitate decarboxylase), and mfs (membrane transporter). By overexpressing each gene of the IA gene cluster in A. terreus AN37 transformed by the restriction enzyme-mediated integration method, several transformants showing high productivity of IA were successfully obtained. One of the AN37/cad transformants could produce a very high amount of IA (75 g/l) in shake-flask cultivations, showing an average of 5% higher IA titer compared with the high-yielding control strain. Notably, in the case of the mfs transformants, a maximal increase of 18.3% in IA production was observed relative to the control strain under the identical fermentation conditions. Meanwhile, the overexpression of reg and mtt genes showed no significant improvements in IA production. In summary, the overexpressed cis-aconitate decarboxylase (CAD) and putative membrane transporter (MFS) appeared to have positive influences on the enhanced IA productivity of the respective transformant. The maximal increases of 13.6~18.3% in IA productivity of the transformed strains should be noted, since the parallel mother strain used in this study is indeed a very high-performance mutant that has been obtained through intensive rational screening programs in our laboratory.

• Korean Journal of Food Science and Technology
• /
• v.36 no.5
• /
• pp.749-753
• /
• 2004

Effects of olive oil on rheological properties of wheat flour dough were investigated through farinograph, amylograph, and extensograph, and by measuring wheat flour dough fermentation volume. Farinogram showed development time, stability, elasticity, and valorimeter value of olive oil-added wheat flour decreased, whereas water absorption and stability were similar to control (shortening 4%). Gelatinization temperature and maximum viscosity of wheat flour dough with olive oil decreased more than those of control as revealed by amylogram. Extensogram showed wheat flour area increased, whereas dough volume decreased in olive oil-added wheat flour dough.